vcsserver: implement set head ref and optimize deletion of filenodes

vcsserver/git.py

@@ -1,1257 +1,1281 b''
 # RhodeCode VCSServer provides access to different vcs backends via network.
 # Copyright (C) 2014-2020 RhodeCode GmbH
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software Foundation,
 # Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
 import collections
 import logging
 import os
 import posixpath as vcspath
 import re
 import stat
 import traceback
 import urllib
 import urllib2
 from functools import wraps
 
 import more_itertools
 import pygit2
 from pygit2 import Repository as LibGit2Repo
 from pygit2 import index as LibGit2Index
 from dulwich import index, objects
 from dulwich.client import HttpGitClient, LocalGitClient
 from dulwich.errors import (
     NotGitRepository, ChecksumMismatch, WrongObjectException,
     MissingCommitError, ObjectMissing, HangupException,
     UnexpectedCommandError)
 from dulwich.repo import Repo as DulwichRepo
 from dulwich.server import update_server_info
 
 from vcsserver import exceptions, settings, subprocessio
 from vcsserver.utils import safe_str, safe_int, safe_unicode
 from vcsserver.base import RepoFactory, obfuscate_qs, ArchiveNode, archive_repo
 from vcsserver.hgcompat import (
     hg_url as url_parser, httpbasicauthhandler, httpdigestauthhandler)
 from vcsserver.git_lfs.lib import LFSOidStore
 from vcsserver.vcs_base import RemoteBase
 
 DIR_STAT = stat.S_IFDIR
 FILE_MODE = stat.S_IFMT
 GIT_LINK = objects.S_IFGITLINK
 PEELED_REF_MARKER = '^{}'
 
 
 log = logging.getLogger(__name__)
 
 
 def str_to_dulwich(value):
     """
     Dulwich 0.10.1a requires `unicode` objects to be passed in.
     """
     return value.decode(settings.WIRE_ENCODING)
 
 
 def reraise_safe_exceptions(func):
     """Converts Dulwich exceptions to something neutral."""
 
     @wraps(func)
     def wrapper(*args, **kwargs):
         try:
             return func(*args, **kwargs)
         except (ChecksumMismatch, WrongObjectException, MissingCommitError, ObjectMissing,) as e:
             exc = exceptions.LookupException(org_exc=e)
             raise exc(safe_str(e))
         except (HangupException, UnexpectedCommandError) as e:
             exc = exceptions.VcsException(org_exc=e)
             raise exc(safe_str(e))
         except Exception as e:
             # NOTE(marcink): becuase of how dulwich handles some exceptions
             # (KeyError on empty repos), we cannot track this and catch all
             # exceptions, it's an exceptions from other handlers
             #if not hasattr(e, '_vcs_kind'):
                 #log.exception("Unhandled exception in git remote call")
                 #raise_from_original(exceptions.UnhandledException)
             raise
     return wrapper
 
 
 class Repo(DulwichRepo):
     """
     A wrapper for dulwich Repo class.
 
     Since dulwich is sometimes keeping .idx file descriptors open, it leads to
     "Too many open files" error. We need to close all opened file descriptors
     once the repo object is destroyed.
     """
     def __del__(self):
         if hasattr(self, 'object_store'):
             self.close()
 
 
 class Repository(LibGit2Repo):
 
     def __enter__(self):
         return self
 
     def __exit__(self, exc_type, exc_val, exc_tb):
         self.free()
 
 
 class GitFactory(RepoFactory):
     repo_type = 'git'
 
     def _create_repo(self, wire, create, use_libgit2=False):
         if use_libgit2:
             return Repository(wire['path'])
         else:
             repo_path = str_to_dulwich(wire['path'])
             return Repo(repo_path)
 
     def repo(self, wire, create=False, use_libgit2=False):
         """
         Get a repository instance for the given path.
         """
         return self._create_repo(wire, create, use_libgit2)
 
     def repo_libgit2(self, wire):
         return self.repo(wire, use_libgit2=True)
 
 
 class GitRemote(RemoteBase):
 
     def __init__(self, factory):
         self._factory = factory
         self._bulk_methods = {
             "date": self.date,
             "author": self.author,
             "branch": self.branch,
             "message": self.message,
             "parents": self.parents,
             "_commit": self.revision,
         }
 
     def _wire_to_config(self, wire):
         if 'config' in wire:
             return dict([(x[0] + '_' + x[1], x[2]) for x in wire['config']])
         return {}
 
     def _remote_conf(self, config):
         params = [
             '-c', 'core.askpass=""',
         ]
         ssl_cert_dir = config.get('vcs_ssl_dir')
         if ssl_cert_dir:
             params.extend(['-c', 'http.sslCAinfo={}'.format(ssl_cert_dir)])
         return params
 
     @reraise_safe_exceptions
     def discover_git_version(self):
         stdout, _ = self.run_git_command(
             {}, ['--version'], _bare=True, _safe=True)
         prefix = 'git version'
         if stdout.startswith(prefix):
             stdout = stdout[len(prefix):]
         return stdout.strip()
 
     @reraise_safe_exceptions
     def is_empty(self, wire):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
 
             try:
                 has_head = repo.head.name
                 if has_head:
                     return False
 
                 # NOTE(marcink): check again using more expensive method
                 return repo.is_empty
             except Exception:
                 pass
 
             return True
 
     @reraise_safe_exceptions
     def assert_correct_path(self, wire):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _assert_correct_path(_context_uid, _repo_id):
             try:
                 repo_init = self._factory.repo_libgit2(wire)
                 with repo_init as repo:
                     pass
             except pygit2.GitError:
                 path = wire.get('path')
                 tb = traceback.format_exc()
                 log.debug("Invalid Git path `%s`, tb: %s", path, tb)
                 return False
 
             return True
         return _assert_correct_path(context_uid, repo_id)
 
     @reraise_safe_exceptions
     def bare(self, wire):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             return repo.is_bare
 
     @reraise_safe_exceptions
     def blob_as_pretty_string(self, wire, sha):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             blob_obj = repo[sha]
             blob = blob_obj.data
             return blob
 
     @reraise_safe_exceptions
     def blob_raw_length(self, wire, sha):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _blob_raw_length(_repo_id, _sha):
 
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 blob = repo[sha]
                 return blob.size
 
         return _blob_raw_length(repo_id, sha)
 
     def _parse_lfs_pointer(self, raw_content):
 
         spec_string = 'version https://git-lfs.github.com/spec'
         if raw_content and raw_content.startswith(spec_string):
             pattern = re.compile(r"""
             (?:\n)?
             ^version[ ]https://git-lfs\.github\.com/spec/(?P<spec_ver>v\d+)\n
             ^oid[ ] sha256:(?P<oid_hash>[0-9a-f]{64})\n
             ^size[ ](?P<oid_size>[0-9]+)\n
             (?:\n)?
             """, re.VERBOSE | re.MULTILINE)
             match = pattern.match(raw_content)
             if match:
                 return match.groupdict()
 
         return {}
 
     @reraise_safe_exceptions
     def is_large_file(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
 
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _is_large_file(_repo_id, _sha):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 blob = repo[commit_id]
                 if blob.is_binary:
                     return {}
 
                 return self._parse_lfs_pointer(blob.data)
 
         return _is_large_file(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def is_binary(self, wire, tree_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
 
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _is_binary(_repo_id, _tree_id):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 blob_obj = repo[tree_id]
                 return blob_obj.is_binary
 
         return _is_binary(repo_id, tree_id)
 
     @reraise_safe_exceptions
     def in_largefiles_store(self, wire, oid):
         conf = self._wire_to_config(wire)
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             repo_name = repo.path
 
         store_location = conf.get('vcs_git_lfs_store_location')
         if store_location:
 
             store = LFSOidStore(
                 oid=oid, repo=repo_name, store_location=store_location)
             return store.has_oid()
 
         return False
 
     @reraise_safe_exceptions
     def store_path(self, wire, oid):
         conf = self._wire_to_config(wire)
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             repo_name = repo.path
 
         store_location = conf.get('vcs_git_lfs_store_location')
         if store_location:
             store = LFSOidStore(
                 oid=oid, repo=repo_name, store_location=store_location)
             return store.oid_path
         raise ValueError('Unable to fetch oid with path {}'.format(oid))
 
     @reraise_safe_exceptions
     def bulk_request(self, wire, rev, pre_load):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _bulk_request(_repo_id, _rev, _pre_load):
             result = {}
             for attr in pre_load:
                 try:
                     method = self._bulk_methods[attr]
                     args = [wire, rev]
                     result[attr] = method(*args)
                 except KeyError as e:
                     raise exceptions.VcsException(e)(
                         "Unknown bulk attribute: %s" % attr)
             return result
 
         return _bulk_request(repo_id, rev, sorted(pre_load))
 
     def _build_opener(self, url):
         handlers = []
         url_obj = url_parser(url)
         _, authinfo = url_obj.authinfo()
 
         if authinfo:
             # create a password manager
             passmgr = urllib2.HTTPPasswordMgrWithDefaultRealm()
             passmgr.add_password(*authinfo)
 
             handlers.extend((httpbasicauthhandler(passmgr),
                              httpdigestauthhandler(passmgr)))
 
         return urllib2.build_opener(*handlers)
 
     def _type_id_to_name(self, type_id):
         return {
             1: b'commit',
             2: b'tree',
             3: b'blob',
             4: b'tag'
         }[type_id]
 
     @reraise_safe_exceptions
     def check_url(self, url, config):
         url_obj = url_parser(url)
         test_uri, _ = url_obj.authinfo()
         url_obj.passwd = '*****' if url_obj.passwd else url_obj.passwd
         url_obj.query = obfuscate_qs(url_obj.query)
         cleaned_uri = str(url_obj)
         log.info("Checking URL for remote cloning/import: %s", cleaned_uri)
 
         if not test_uri.endswith('info/refs'):
             test_uri = test_uri.rstrip('/') + '/info/refs'
 
         o = self._build_opener(url)
         o.addheaders = [('User-Agent', 'git/1.7.8.0')]  # fake some git
 
         q = {"service": 'git-upload-pack'}
         qs = '?%s' % urllib.urlencode(q)
         cu = "%s%s" % (test_uri, qs)
         req = urllib2.Request(cu, None, {})
 
         try:
             log.debug("Trying to open URL %s", cleaned_uri)
             resp = o.open(req)
             if resp.code != 200:
                 raise exceptions.URLError()('Return Code is not 200')
         except Exception as e:
             log.warning("URL cannot be opened: %s", cleaned_uri, exc_info=True)
             # means it cannot be cloned
             raise exceptions.URLError(e)("[%s] org_exc: %s" % (cleaned_uri, e))
 
         # now detect if it's proper git repo
         gitdata = resp.read()
         if 'service=git-upload-pack' in gitdata:
             pass
         elif re.findall(r'[0-9a-fA-F]{40}\s+refs', gitdata):
             # old style git can return some other format !
             pass
         else:
             raise exceptions.URLError()(
                 "url [%s] does not look like an git" % (cleaned_uri,))
 
         return True
 
     @reraise_safe_exceptions
     def clone(self, wire, url, deferred, valid_refs, update_after_clone):
         # TODO(marcink): deprecate this method. Last i checked we don't use it anymore
         remote_refs = self.pull(wire, url, apply_refs=False)
         repo = self._factory.repo(wire)
         if isinstance(valid_refs, list):
             valid_refs = tuple(valid_refs)
 
         for k in remote_refs:
             # only parse heads/tags and skip so called deferred tags
             if k.startswith(valid_refs) and not k.endswith(deferred):
                 repo[k] = remote_refs[k]
 
         if update_after_clone:
             # we want to checkout HEAD
             repo["HEAD"] = remote_refs["HEAD"]
             index.build_index_from_tree(repo.path, repo.index_path(),
                                         repo.object_store, repo["HEAD"].tree)
 
     @reraise_safe_exceptions
     def branch(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _branch(_context_uid, _repo_id, _commit_id):
             regex = re.compile('^refs/heads')
 
             def filter_with(ref):
                 return regex.match(ref[0]) and ref[1] == _commit_id
 
             branches = filter(filter_with, self.get_refs(wire).items())
             return [x[0].split('refs/heads/')[-1] for x in branches]
 
         return _branch(context_uid, repo_id, commit_id)
 
     @reraise_safe_exceptions
     def commit_branches(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _commit_branches(_context_uid, _repo_id, _commit_id):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 branches = [x for x in repo.branches.with_commit(_commit_id)]
                 return branches
 
         return _commit_branches(context_uid, repo_id, commit_id)
 
     @reraise_safe_exceptions
     def add_object(self, wire, content):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             blob = objects.Blob()
             blob.set_raw_string(content)
             repo.object_store.add_object(blob)
             return blob.id
 
     # TODO: this is quite complex, check if that can be simplified
     @reraise_safe_exceptions
     def commit(self, wire, commit_data, branch, commit_tree, updated, removed):
+        # Defines the root tree
+        class _Root(object):
+            def __repr__(self):
+                return 'ROOT TREE'
+        ROOT = _Root()
+
         repo = self._factory.repo(wire)
         object_store = repo.object_store
 
         # Create tree and populates it with blobs
-        commit_tree = commit_tree and repo[commit_tree] or objects.Tree()
+
+        if commit_tree and repo[commit_tree]:
+            git_commit = repo[commit_data['parents'][0]]
+            commit_tree = repo[git_commit.tree]  # root tree
+        else:
+            commit_tree = objects.Tree()
 
         for node in updated:
             # Compute subdirs if needed
             dirpath, nodename = vcspath.split(node['path'])
             dirnames = map(safe_str, dirpath and dirpath.split('/') or [])
             parent = commit_tree
             ancestors = [('', parent)]
 
             # Tries to dig for the deepest existing tree
             while dirnames:
                 curdir = dirnames.pop(0)
                 try:
                     dir_id = parent[curdir][1]
                 except KeyError:
                     # put curdir back into dirnames and stops
                     dirnames.insert(0, curdir)
                     break
                 else:
                     # If found, updates parent
                     parent = repo[dir_id]
                     ancestors.append((curdir, parent))
             # Now parent is deepest existing tree and we need to create
             # subtrees for dirnames (in reverse order)
             # [this only applies for nodes from added]
             new_trees = []
 
             blob = objects.Blob.from_string(node['content'])
 
             if dirnames:
                 # If there are trees which should be created we need to build
                 # them now (in reverse order)
                 reversed_dirnames = list(reversed(dirnames))
                 curtree = objects.Tree()
                 curtree[node['node_path']] = node['mode'], blob.id
                 new_trees.append(curtree)
                 for dirname in reversed_dirnames[:-1]:
                     newtree = objects.Tree()
                     newtree[dirname] = (DIR_STAT, curtree.id)
                     new_trees.append(newtree)
                     curtree = newtree
                 parent[reversed_dirnames[-1]] = (DIR_STAT, curtree.id)
             else:
                 parent.add(name=node['node_path'], mode=node['mode'], hexsha=blob.id)
 
             new_trees.append(parent)
             # Update ancestors
             reversed_ancestors = reversed(
                 [(a[1], b[1], b[0]) for a, b in zip(ancestors, ancestors[1:])])
             for parent, tree, path in reversed_ancestors:
                 parent[path] = (DIR_STAT, tree.id)
                 object_store.add_object(tree)
 
             object_store.add_object(blob)
             for tree in new_trees:
                 object_store.add_object(tree)
 
         for node_path in removed:
             paths = node_path.split('/')
-            tree = commit_tree
-            trees = [tree]
+            tree = commit_tree  # start with top-level
+            trees = [{'tree': tree, 'path': ROOT}]
             # Traverse deep into the forest...
+            # resolve final tree by iterating the path.
+            # e.g a/b/c.txt will get
+            # - root as tree then
+            # - 'a' as tree,
+            # - 'b' as tree,
+            # - stop at c as blob.
             for path in paths:
                 try:
                     obj = repo[tree[path][1]]
                     if isinstance(obj, objects.Tree):
-                        trees.append(obj)
+                        trees.append({'tree': obj, 'path': path})
                         tree = obj
                 except KeyError:
                     break
+            #PROBLEM:
+            """
+            We're not editing same reference tree object
+            """
             # Cut down the blob and all rotten trees on the way back...
-            for path, tree in reversed(zip(paths, trees)):
-                del tree[path]
-                if tree:
+            for path, tree_data in reversed(zip(paths, trees)):
+                tree = tree_data['tree']
+                tree.__delitem__(path)
+                # This operation edits the tree, we need to mark new commit back
+
+                if len(tree) > 0:
                     # This tree still has elements - don't remove it or any
                     # of it's parents
                     break
 
         object_store.add_object(commit_tree)
 
         # Create commit
         commit = objects.Commit()
         commit.tree = commit_tree.id
-        for k, v in commit_data.iteritems():
+        for k, v in commit_data.items():
             setattr(commit, k, v)
         object_store.add_object(commit)
 
         self.create_branch(wire, branch, commit.id)
 
         # dulwich set-ref
         ref = 'refs/heads/%s' % branch
         repo.refs[ref] = commit.id
 
         return commit.id
 
     @reraise_safe_exceptions
     def pull(self, wire, url, apply_refs=True, refs=None, update_after=False):
         if url != 'default' and '://' not in url:
             client = LocalGitClient(url)
         else:
             url_obj = url_parser(url)
             o = self._build_opener(url)
             url, _ = url_obj.authinfo()
             client = HttpGitClient(base_url=url, opener=o)
         repo = self._factory.repo(wire)
 
         determine_wants = repo.object_store.determine_wants_all
         if refs:
             def determine_wants_requested(references):
                 return [references[r] for r in references if r in refs]
             determine_wants = determine_wants_requested
 
         try:
             remote_refs = client.fetch(
                 path=url, target=repo, determine_wants=determine_wants)
         except NotGitRepository as e:
             log.warning(
                 'Trying to fetch from "%s" failed, not a Git repository.', url)
             # Exception can contain unicode which we convert
             raise exceptions.AbortException(e)(repr(e))
 
         # mikhail: client.fetch() returns all the remote refs, but fetches only
         # refs filtered by `determine_wants` function. We need to filter result
         # as well
         if refs:
             remote_refs = {k: remote_refs[k] for k in remote_refs if k in refs}
 
         if apply_refs:
             # TODO: johbo: Needs proper test coverage with a git repository
             # that contains a tag object, so that we would end up with
             # a peeled ref at this point.
             for k in remote_refs:
                 if k.endswith(PEELED_REF_MARKER):
                     log.debug("Skipping peeled reference %s", k)
                     continue
                 repo[k] = remote_refs[k]
 
             if refs and not update_after:
                 # mikhail: explicitly set the head to the last ref.
                 repo["HEAD"] = remote_refs[refs[-1]]
 
         if update_after:
             # we want to checkout HEAD
             repo["HEAD"] = remote_refs["HEAD"]
             index.build_index_from_tree(repo.path, repo.index_path(),
                                         repo.object_store, repo["HEAD"].tree)
         return remote_refs
 
     @reraise_safe_exceptions
     def sync_fetch(self, wire, url, refs=None, all_refs=False):
         repo = self._factory.repo(wire)
         if refs and not isinstance(refs, (list, tuple)):
             refs = [refs]
 
         config = self._wire_to_config(wire)
         # get all remote refs we'll use to fetch later
         cmd = ['ls-remote']
         if not all_refs:
             cmd += ['--heads', '--tags']
         cmd += [url]
         output, __ = self.run_git_command(
             wire, cmd, fail_on_stderr=False,
             _copts=self._remote_conf(config),
             extra_env={'GIT_TERMINAL_PROMPT': '0'})
 
         remote_refs = collections.OrderedDict()
         fetch_refs = []
 
         for ref_line in output.splitlines():
             sha, ref = ref_line.split('\t')
             sha = sha.strip()
             if ref in remote_refs:
                 # duplicate, skip
                 continue
             if ref.endswith(PEELED_REF_MARKER):
                 log.debug("Skipping peeled reference %s", ref)
                 continue
             # don't sync HEAD
             if ref in ['HEAD']:
                 continue
 
             remote_refs[ref] = sha
 
             if refs and sha in refs:
                 # we filter fetch using our specified refs
                 fetch_refs.append('{}:{}'.format(ref, ref))
             elif not refs:
                 fetch_refs.append('{}:{}'.format(ref, ref))
         log.debug('Finished obtaining fetch refs, total: %s', len(fetch_refs))
 
         if fetch_refs:
             for chunk in more_itertools.chunked(fetch_refs, 1024 * 4):
                 fetch_refs_chunks = list(chunk)
                 log.debug('Fetching %s refs from import url', len(fetch_refs_chunks))
                 _out, _err = self.run_git_command(
                     wire, ['fetch', url, '--force', '--prune', '--'] + fetch_refs_chunks,
                     fail_on_stderr=False,
                     _copts=self._remote_conf(config),
                     extra_env={'GIT_TERMINAL_PROMPT': '0'})
 
         return remote_refs
 
     @reraise_safe_exceptions
     def sync_push(self, wire, url, refs=None):
         if not self.check_url(url, wire):
             return
         config = self._wire_to_config(wire)
         self._factory.repo(wire)
         self.run_git_command(
             wire, ['push', url, '--mirror'], fail_on_stderr=False,
             _copts=self._remote_conf(config),
             extra_env={'GIT_TERMINAL_PROMPT': '0'})
 
     @reraise_safe_exceptions
     def get_remote_refs(self, wire, url):
         repo = Repo(url)
         return repo.get_refs()
 
     @reraise_safe_exceptions
     def get_description(self, wire):
         repo = self._factory.repo(wire)
         return repo.get_description()
 
     @reraise_safe_exceptions
     def get_missing_revs(self, wire, rev1, rev2, path2):
         repo = self._factory.repo(wire)
         LocalGitClient(thin_packs=False).fetch(path2, repo)
 
         wire_remote = wire.copy()
         wire_remote['path'] = path2
         repo_remote = self._factory.repo(wire_remote)
         LocalGitClient(thin_packs=False).fetch(wire["path"], repo_remote)
 
         revs = [
             x.commit.id
             for x in repo_remote.get_walker(include=[rev2], exclude=[rev1])]
         return revs
 
     @reraise_safe_exceptions
     def get_object(self, wire, sha, maybe_unreachable=False):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_object(_context_uid, _repo_id, _sha):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
 
                 missing_commit_err = 'Commit {} does not exist for `{}`'.format(sha, wire['path'])
                 try:
                     commit = repo.revparse_single(sha)
                 except KeyError:
                     # NOTE(marcink): KeyError doesn't give us any meaningful information
                     # here, we instead give something more explicit
                     e = exceptions.RefNotFoundException('SHA: %s not found', sha)
                     raise exceptions.LookupException(e)(missing_commit_err)
                 except ValueError as e:
                     raise exceptions.LookupException(e)(missing_commit_err)
 
                 is_tag = False
                 if isinstance(commit, pygit2.Tag):
                     commit = repo.get(commit.target)
                     is_tag = True
 
                 check_dangling = True
                 if is_tag:
                     check_dangling = False
 
                 if check_dangling and maybe_unreachable:
                     check_dangling = False
 
                 # we used a reference and it parsed means we're not having a dangling commit
                 if sha != commit.hex:
                     check_dangling = False
 
                 if check_dangling:
                     # check for dangling commit
                     for branch in repo.branches.with_commit(commit.hex):
                         if branch:
                             break
                     else:
                         # NOTE(marcink): Empty error doesn't give us any meaningful information
                         # here, we instead give something more explicit
                         e = exceptions.RefNotFoundException('SHA: %s not found in branches', sha)
                         raise exceptions.LookupException(e)(missing_commit_err)
 
                 commit_id = commit.hex
                 type_id = commit.type
 
                 return {
                     'id': commit_id,
                     'type': self._type_id_to_name(type_id),
                     'commit_id': commit_id,
                     'idx': 0
                 }
 
         return _get_object(context_uid, repo_id, sha)
 
     @reraise_safe_exceptions
     def get_refs(self, wire):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_refs(_context_uid, _repo_id):
 
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 regex = re.compile('^refs/(heads|tags)/')
                 return {x.name: x.target.hex for x in
                         filter(lambda ref: regex.match(ref.name) ,repo.listall_reference_objects())}
 
         return _get_refs(context_uid, repo_id)
 
     @reraise_safe_exceptions
     def get_branch_pointers(self, wire):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_branch_pointers(_context_uid, _repo_id):
 
             repo_init = self._factory.repo_libgit2(wire)
             regex = re.compile('^refs/heads')
             with repo_init as repo:
                 branches = filter(lambda ref: regex.match(ref.name), repo.listall_reference_objects())
                 return {x.target.hex: x.shorthand for x in branches}
 
         return _get_branch_pointers(context_uid, repo_id)
 
     @reraise_safe_exceptions
     def head(self, wire, show_exc=True):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _head(_context_uid, _repo_id, _show_exc):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 try:
                     return repo.head.peel().hex
                 except Exception:
                     if show_exc:
                         raise
         return _head(context_uid, repo_id, show_exc)
 
     @reraise_safe_exceptions
     def init(self, wire):
         repo_path = str_to_dulwich(wire['path'])
         self.repo = Repo.init(repo_path)
 
     @reraise_safe_exceptions
     def init_bare(self, wire):
         repo_path = str_to_dulwich(wire['path'])
         self.repo = Repo.init_bare(repo_path)
 
     @reraise_safe_exceptions
     def revision(self, wire, rev):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _revision(_context_uid, _repo_id, _rev):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 commit = repo[rev]
                 obj_data = {
                     'id': commit.id.hex,
                 }
                 # tree objects itself don't have tree_id attribute
                 if hasattr(commit, 'tree_id'):
                     obj_data['tree'] = commit.tree_id.hex
 
                 return obj_data
         return _revision(context_uid, repo_id, rev)
 
     @reraise_safe_exceptions
     def date(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _date(_repo_id, _commit_id):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 commit = repo[commit_id]
 
                 if hasattr(commit, 'commit_time'):
                     commit_time, commit_time_offset = commit.commit_time, commit.commit_time_offset
                 else:
                     commit = commit.get_object()
                     commit_time, commit_time_offset = commit.commit_time, commit.commit_time_offset
 
                 # TODO(marcink): check dulwich difference of offset vs timezone
                 return [commit_time, commit_time_offset]
         return _date(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def author(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _author(_repo_id, _commit_id):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 commit = repo[commit_id]
 
                 if hasattr(commit, 'author'):
                     author = commit.author
                 else:
                     author = commit.get_object().author
 
                 if author.email:
                     return u"{} <{}>".format(author.name, author.email)
 
                 try:
                     return u"{}".format(author.name)
                 except Exception:
                     return u"{}".format(safe_unicode(author.raw_name))
 
         return _author(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def message(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _message(_repo_id, _commit_id):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 commit = repo[commit_id]
                 return commit.message
         return _message(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def parents(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _parents(_repo_id, _commit_id):
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 commit = repo[commit_id]
                 if hasattr(commit, 'parent_ids'):
                     parent_ids = commit.parent_ids
                 else:
                     parent_ids = commit.get_object().parent_ids
 
                 return [x.hex for x in parent_ids]
         return _parents(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def children(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _children(_repo_id, _commit_id):
             output, __ = self.run_git_command(
                 wire, ['rev-list', '--all', '--children'])
 
             child_ids = []
             pat = re.compile(r'^%s' % commit_id)
             for l in output.splitlines():
                 if pat.match(l):
                     found_ids = l.split(' ')[1:]
                     child_ids.extend(found_ids)
 
             return child_ids
         return _children(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def set_refs(self, wire, key, value):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             repo.references.create(key, value, force=True)
 
     @reraise_safe_exceptions
     def create_branch(self, wire, branch_name, commit_id, force=False):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             commit = repo[commit_id]
 
             if force:
                 repo.branches.local.create(branch_name, commit, force=force)
             elif not repo.branches.get(branch_name):
                 # create only if that branch isn't existing
                 repo.branches.local.create(branch_name, commit, force=force)
 
     @reraise_safe_exceptions
     def remove_ref(self, wire, key):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             repo.references.delete(key)
 
     @reraise_safe_exceptions
     def tag_remove(self, wire, tag_name):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             key = 'refs/tags/{}'.format(tag_name)
             repo.references.delete(key)
 
     @reraise_safe_exceptions
     def tree_changes(self, wire, source_id, target_id):
         # TODO(marcink): remove this seems it's only used by tests
         repo = self._factory.repo(wire)
         source = repo[source_id].tree if source_id else None
         target = repo[target_id].tree
         result = repo.object_store.tree_changes(source, target)
         return list(result)
 
     @reraise_safe_exceptions
     def tree_and_type_for_path(self, wire, commit_id, path):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _tree_and_type_for_path(_context_uid, _repo_id, _commit_id, _path):
             repo_init = self._factory.repo_libgit2(wire)
 
             with repo_init as repo:
                 commit = repo[commit_id]
                 try:
                     tree = commit.tree[path]
                 except KeyError:
                     return None, None, None
 
                 return tree.id.hex, tree.type, tree.filemode
         return _tree_and_type_for_path(context_uid, repo_id, commit_id, path)
 
     @reraise_safe_exceptions
     def tree_items(self, wire, tree_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _tree_items(_repo_id, _tree_id):
 
             repo_init = self._factory.repo_libgit2(wire)
             with repo_init as repo:
                 try:
                     tree = repo[tree_id]
                 except KeyError:
                     raise ObjectMissing('No tree with id: {}'.format(tree_id))
 
                 result = []
                 for item in tree:
                     item_sha = item.hex
                     item_mode = item.filemode
                     item_type = item.type
 
                     if item_type == 'commit':
                         # NOTE(marcink): submodules we translate to 'link' for backward compat
                         item_type = 'link'
 
                     result.append((item.name, item_mode, item_sha, item_type))
                 return result
         return _tree_items(repo_id, tree_id)
 
     @reraise_safe_exceptions
     def diff_2(self, wire, commit_id_1, commit_id_2, file_filter, opt_ignorews, context):
         """
         Old version that uses subprocess to call diff
         """
 
         flags = [
             '-U%s' % context, '--patch',
             '--binary',
             '--find-renames',
             '--no-indent-heuristic',
             # '--indent-heuristic',
             #'--full-index',
             #'--abbrev=40'
         ]
 
         if opt_ignorews:
             flags.append('--ignore-all-space')
 
         if commit_id_1 == self.EMPTY_COMMIT:
             cmd = ['show'] + flags + [commit_id_2]
         else:
             cmd = ['diff'] + flags + [commit_id_1, commit_id_2]
 
         if file_filter:
             cmd.extend(['--', file_filter])
 
         diff, __ = self.run_git_command(wire, cmd)
         # If we used 'show' command, strip first few lines (until actual diff
         # starts)
         if commit_id_1 == self.EMPTY_COMMIT:
             lines = diff.splitlines()
             x = 0
             for line in lines:
                 if line.startswith('diff'):
                     break
                 x += 1
             # Append new line just like 'diff' command do
             diff = '\n'.join(lines[x:]) + '\n'
         return diff
 
     @reraise_safe_exceptions
     def diff(self, wire, commit_id_1, commit_id_2, file_filter, opt_ignorews, context):
         repo_init = self._factory.repo_libgit2(wire)
         with repo_init as repo:
             swap = True
             flags = 0
             flags |= pygit2.GIT_DIFF_SHOW_BINARY
 
             if opt_ignorews:
                 flags |= pygit2.GIT_DIFF_IGNORE_WHITESPACE
 
             if commit_id_1 == self.EMPTY_COMMIT:
                 comm1 = repo[commit_id_2]
                 diff_obj = comm1.tree.diff_to_tree(
                     flags=flags, context_lines=context, swap=swap)
 
             else:
                 comm1 = repo[commit_id_2]
                 comm2 = repo[commit_id_1]
                 diff_obj = comm1.tree.diff_to_tree(
                     comm2.tree, flags=flags, context_lines=context, swap=swap)
             similar_flags = 0
             similar_flags |= pygit2.GIT_DIFF_FIND_RENAMES
             diff_obj.find_similar(flags=similar_flags)
 
             if file_filter:
                 for p in diff_obj:
                     if p.delta.old_file.path == file_filter:
                         return p.patch or ''
                 # fo matching path == no diff
                 return ''
             return diff_obj.patch or ''
 
     @reraise_safe_exceptions
     def node_history(self, wire, commit_id, path, limit):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _node_history(_context_uid, _repo_id, _commit_id, _path, _limit):
             # optimize for n==1, rev-list is much faster for that use-case
             if limit == 1:
                 cmd = ['rev-list', '-1', commit_id, '--', path]
             else:
                 cmd = ['log']
                 if limit:
                     cmd.extend(['-n', str(safe_int(limit, 0))])
                 cmd.extend(['--pretty=format: %H', '-s', commit_id, '--', path])
 
             output, __ = self.run_git_command(wire, cmd)
             commit_ids = re.findall(r'[0-9a-fA-F]{40}', output)
 
             return [x for x in commit_ids]
         return _node_history(context_uid, repo_id, commit_id, path, limit)
 
     @reraise_safe_exceptions
     def node_annotate(self, wire, commit_id, path):
 
         cmd = ['blame', '-l', '--root', '-r', commit_id, '--', path]
         # -l     ==> outputs long shas (and we need all 40 characters)
         # --root ==> doesn't put '^' character for boundaries
         # -r commit_id ==> blames for the given commit
         output, __ = self.run_git_command(wire, cmd)
 
         result = []
         for i, blame_line in enumerate(output.split('\n')[:-1]):
             line_no = i + 1
             commit_id, line = re.split(r' ', blame_line, 1)
             result.append((line_no, commit_id, line))
         return result
 
     @reraise_safe_exceptions
     def update_server_info(self, wire):
         repo = self._factory.repo(wire)
         update_server_info(repo)
 
     @reraise_safe_exceptions
     def get_all_commit_ids(self, wire):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_all_commit_ids(_context_uid, _repo_id):
 
             cmd = ['rev-list', '--reverse', '--date-order', '--branches', '--tags']
             try:
                 output, __ = self.run_git_command(wire, cmd)
                 return output.splitlines()
             except Exception:
                 # Can be raised for empty repositories
                 return []
         return _get_all_commit_ids(context_uid, repo_id)
 
     @reraise_safe_exceptions
     def run_git_command(self, wire, cmd, **opts):
         path = wire.get('path', None)
 
         if path and os.path.isdir(path):
             opts['cwd'] = path
 
         if '_bare' in opts:
             _copts = []
             del opts['_bare']
         else:
             _copts = ['-c', 'core.quotepath=false', ]
         safe_call = False
         if '_safe' in opts:
             # no exc on failure
             del opts['_safe']
             safe_call = True
 
         if '_copts' in opts:
             _copts.extend(opts['_copts'] or [])
             del opts['_copts']
 
         gitenv = os.environ.copy()
         gitenv.update(opts.pop('extra_env', {}))
         # need to clean fix GIT_DIR !
         if 'GIT_DIR' in gitenv:
             del gitenv['GIT_DIR']
         gitenv['GIT_CONFIG_NOGLOBAL'] = '1'
         gitenv['GIT_DISCOVERY_ACROSS_FILESYSTEM'] = '1'
 
         cmd = [settings.GIT_EXECUTABLE] + _copts + cmd
         _opts = {'env': gitenv, 'shell': False}
 
         proc = None
         try:
             _opts.update(opts)
             proc = subprocessio.SubprocessIOChunker(cmd, **_opts)
 
             return ''.join(proc), ''.join(proc.error)
         except (EnvironmentError, OSError) as err:
             cmd = ' '.join(cmd)  # human friendly CMD
             tb_err = ("Couldn't run git command (%s).\n"
                       "Original error was:%s\n"
                       "Call options:%s\n"
                       % (cmd, err, _opts))
             log.exception(tb_err)
             if safe_call:
                 return '', err
             else:
                 raise exceptions.VcsException()(tb_err)
         finally:
             if proc:
                 proc.close()
 
     @reraise_safe_exceptions
     def install_hooks(self, wire, force=False):
         from vcsserver.hook_utils import install_git_hooks
         bare = self.bare(wire)
         path = wire['path']
         return install_git_hooks(path, bare, force_create=force)
 
     @reraise_safe_exceptions
-    def set_head_ref(self, wire, head_name):
-        log.debug('Setting refs/head to `%s`', head_name)
-        cmd = ['symbolic-ref', 'HEAD', 'refs/heads/%s' % head_name]
-        output, __ = self.run_git_command(wire, cmd)
-        return [head_name] + output.splitlines()
-
-    @reraise_safe_exceptions
     def get_hooks_info(self, wire):
         from vcsserver.hook_utils import (
             get_git_pre_hook_version, get_git_post_hook_version)
         bare = self.bare(wire)
         path = wire['path']
         return {
             'pre_version': get_git_pre_hook_version(path, bare),
             'post_version': get_git_post_hook_version(path, bare),
         }
 
     @reraise_safe_exceptions
+    def set_head_ref(self, wire, head_name):
+        log.debug('Setting refs/head to `%s`', head_name)
+        cmd = ['symbolic-ref', 'HEAD', 'refs/heads/%s' % head_name]
+        output, __ = self.run_git_command(wire, cmd)
+        return [head_name] + output.splitlines()
+
+    @reraise_safe_exceptions
     def archive_repo(self, wire, archive_dest_path, kind, mtime, archive_at_path,
                      archive_dir_name, commit_id):
 
         def file_walker(_commit_id, path):
             repo_init = self._factory.repo_libgit2(wire)
 
             with repo_init as repo:
                 commit = repo[commit_id]
 
                 if path in ['', '/']:
                     tree = commit.tree
                 else:
                     tree = commit.tree[path.rstrip('/')]
                     tree_id = tree.id.hex
                     try:
                         tree = repo[tree_id]
                     except KeyError:
                         raise ObjectMissing('No tree with id: {}'.format(tree_id))
 
                 index = LibGit2Index.Index()
                 index.read_tree(tree)
                 file_iter = index
 
                 for fn in file_iter:
                     file_path = fn.path
                     mode = fn.mode
                     is_link = stat.S_ISLNK(mode)
                     if mode == pygit2.GIT_FILEMODE_COMMIT:
                         log.debug('Skipping path %s as a commit node', file_path)
                         continue
                     yield ArchiveNode(file_path, mode, is_link, repo[fn.hex].read_raw)
 
         return archive_repo(file_walker, archive_dest_path, kind, mtime, archive_at_path,
                             archive_dir_name, commit_id)

vcsserver/hg.py

@@ -1,1043 +1,1047 b''
 # RhodeCode VCSServer provides access to different vcs backends via network.
 # Copyright (C) 2014-2020 RhodeCode GmbH
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software Foundation,
 # Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 import functools
 import io
 import logging
 import os
 import stat
 import urllib
 import urllib2
 import traceback
 
 from hgext import largefiles, rebase, purge
 from hgext.strip import strip as hgext_strip
 from mercurial import commands
 from mercurial import unionrepo
 from mercurial import verify
 from mercurial import repair
 
 import vcsserver
 from vcsserver import exceptions
 from vcsserver.base import RepoFactory, obfuscate_qs, raise_from_original, archive_repo, ArchiveNode
 from vcsserver.hgcompat import (
     archival, bin, clone, config as hgconfig, diffopts, hex, get_ctx,
     hg_url as url_parser, httpbasicauthhandler, httpdigestauthhandler,
     makepeer, instance, match, memctx, exchange, memfilectx, nullrev, hg_merge,
     patch, peer, revrange, ui, hg_tag, Abort, LookupError, RepoError,
     RepoLookupError, InterventionRequired, RequirementError,
     alwaysmatcher, patternmatcher, hgutil)
 from vcsserver.vcs_base import RemoteBase
 
 log = logging.getLogger(__name__)
 
 
 def make_ui_from_config(repo_config):
 
     class LoggingUI(ui.ui):
         def status(self, *msg, **opts):
             log.info(' '.join(msg).rstrip('\n'))
             super(LoggingUI, self).status(*msg, **opts)
 
         def warn(self, *msg, **opts):
             log.warn(' '.join(msg).rstrip('\n'))
             super(LoggingUI, self).warn(*msg, **opts)
 
         def error(self, *msg, **opts):
             log.error(' '.join(msg).rstrip('\n'))
             super(LoggingUI, self).error(*msg, **opts)
 
         def note(self, *msg, **opts):
             log.info(' '.join(msg).rstrip('\n'))
             super(LoggingUI, self).note(*msg, **opts)
 
         def debug(self, *msg, **opts):
             log.debug(' '.join(msg).rstrip('\n'))
             super(LoggingUI, self).debug(*msg, **opts)
 
     baseui = LoggingUI()
 
     # clean the baseui object
     baseui._ocfg = hgconfig.config()
     baseui._ucfg = hgconfig.config()
     baseui._tcfg = hgconfig.config()
 
     for section, option, value in repo_config:
         baseui.setconfig(section, option, value)
 
     # make our hgweb quiet so it doesn't print output
     baseui.setconfig('ui', 'quiet', 'true')
 
     baseui.setconfig('ui', 'paginate', 'never')
     # for better Error reporting of Mercurial
     baseui.setconfig('ui', 'message-output', 'stderr')
 
     # force mercurial to only use 1 thread, otherwise it may try to set a
     # signal in a non-main thread, thus generating a ValueError.
     baseui.setconfig('worker', 'numcpus', 1)
 
     # If there is no config for the largefiles extension, we explicitly disable
     # it here. This overrides settings from repositories hgrc file. Recent
     # mercurial versions enable largefiles in hgrc on clone from largefile
     # repo.
     if not baseui.hasconfig('extensions', 'largefiles'):
         log.debug('Explicitly disable largefiles extension for repo.')
         baseui.setconfig('extensions', 'largefiles', '!')
 
     return baseui
 
 
 def reraise_safe_exceptions(func):
     """Decorator for converting mercurial exceptions to something neutral."""
 
     def wrapper(*args, **kwargs):
         try:
             return func(*args, **kwargs)
         except (Abort, InterventionRequired) as e:
             raise_from_original(exceptions.AbortException(e))
         except RepoLookupError as e:
             raise_from_original(exceptions.LookupException(e))
         except RequirementError as e:
             raise_from_original(exceptions.RequirementException(e))
         except RepoError as e:
             raise_from_original(exceptions.VcsException(e))
         except LookupError as e:
             raise_from_original(exceptions.LookupException(e))
         except Exception as e:
             if not hasattr(e, '_vcs_kind'):
                 log.exception("Unhandled exception in hg remote call")
                 raise_from_original(exceptions.UnhandledException(e))
 
             raise
     return wrapper
 
 
 class MercurialFactory(RepoFactory):
     repo_type = 'hg'
 
     def _create_config(self, config, hooks=True):
         if not hooks:
             hooks_to_clean = frozenset((
                 'changegroup.repo_size', 'preoutgoing.pre_pull',
                 'outgoing.pull_logger', 'prechangegroup.pre_push'))
             new_config = []
             for section, option, value in config:
                 if section == 'hooks' and option in hooks_to_clean:
                     continue
                 new_config.append((section, option, value))
             config = new_config
 
         baseui = make_ui_from_config(config)
         return baseui
 
     def _create_repo(self, wire, create):
         baseui = self._create_config(wire["config"])
         return instance(baseui, wire["path"], create)
 
     def repo(self, wire, create=False):
         """
         Get a repository instance for the given path.
         """
         return self._create_repo(wire, create)
 
 
 def patch_ui_message_output(baseui):
     baseui.setconfig('ui', 'quiet', 'false')
     output = io.BytesIO()
 
     def write(data, **unused_kwargs):
         output.write(data)
 
     baseui.status = write
     baseui.write = write
     baseui.warn = write
     baseui.debug = write
 
     return baseui, output
 
 
 class HgRemote(RemoteBase):
 
     def __init__(self, factory):
         self._factory = factory
         self._bulk_methods = {
             "affected_files": self.ctx_files,
             "author": self.ctx_user,
             "branch": self.ctx_branch,
             "children": self.ctx_children,
             "date": self.ctx_date,
             "message": self.ctx_description,
             "parents": self.ctx_parents,
             "status": self.ctx_status,
             "obsolete": self.ctx_obsolete,
             "phase": self.ctx_phase,
             "hidden": self.ctx_hidden,
             "_file_paths": self.ctx_list,
         }
 
     def _get_ctx(self, repo, ref):
         return get_ctx(repo, ref)
 
     @reraise_safe_exceptions
     def discover_hg_version(self):
         from mercurial import util
         return util.version()
 
     @reraise_safe_exceptions
     def is_empty(self, wire):
         repo = self._factory.repo(wire)
 
         try:
             return len(repo) == 0
         except Exception:
             log.exception("failed to read object_store")
             return False
 
     @reraise_safe_exceptions
     def bookmarks(self, wire):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _bookmarks(_context_uid, _repo_id):
             repo = self._factory.repo(wire)
             return dict(repo._bookmarks)
 
         return _bookmarks(context_uid, repo_id)
 
     @reraise_safe_exceptions
     def branches(self, wire, normal, closed):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _branches(_context_uid, _repo_id, _normal, _closed):
             repo = self._factory.repo(wire)
             iter_branches = repo.branchmap().iterbranches()
             bt = {}
             for branch_name, _heads, tip, is_closed in iter_branches:
                 if normal and not is_closed:
                     bt[branch_name] = tip
                 if closed and is_closed:
                     bt[branch_name] = tip
 
             return bt
 
         return _branches(context_uid, repo_id, normal, closed)
 
     @reraise_safe_exceptions
     def bulk_request(self, wire, commit_id, pre_load):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _bulk_request(_repo_id, _commit_id, _pre_load):
             result = {}
             for attr in pre_load:
                 try:
                     method = self._bulk_methods[attr]
                     result[attr] = method(wire, commit_id)
                 except KeyError as e:
                     raise exceptions.VcsException(e)(
                         'Unknown bulk attribute: "%s"' % attr)
             return result
 
         return _bulk_request(repo_id, commit_id, sorted(pre_load))
 
     @reraise_safe_exceptions
     def ctx_branch(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_branch(_repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return ctx.branch()
         return _ctx_branch(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_date(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_date(_repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return ctx.date()
         return _ctx_date(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_description(self, wire, revision):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         return ctx.description()
 
     @reraise_safe_exceptions
     def ctx_files(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_files(_repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return ctx.files()
 
         return _ctx_files(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_list(self, path, revision):
         repo = self._factory.repo(path)
         ctx = self._get_ctx(repo, revision)
         return list(ctx)
 
     @reraise_safe_exceptions
     def ctx_parents(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_parents(_repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return [parent.hex() for parent in ctx.parents()
                     if not (parent.hidden() or parent.obsolete())]
 
         return _ctx_parents(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_children(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_children(_repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return [child.hex() for child in ctx.children()
                     if not (child.hidden() or child.obsolete())]
 
         return _ctx_children(repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_phase(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_phase(_context_uid, _repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             # public=0, draft=1, secret=3
             return ctx.phase()
         return _ctx_phase(context_uid, repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_obsolete(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_obsolete(_context_uid, _repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return ctx.obsolete()
         return _ctx_obsolete(context_uid, repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_hidden(self, wire, commit_id):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _ctx_hidden(_context_uid, _repo_id, _commit_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             return ctx.hidden()
         return _ctx_hidden(context_uid, repo_id, commit_id)
 
     @reraise_safe_exceptions
     def ctx_substate(self, wire, revision):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         return ctx.substate
 
     @reraise_safe_exceptions
     def ctx_status(self, wire, revision):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         status = repo[ctx.p1().node()].status(other=ctx.node())
         # object of status (odd, custom named tuple in mercurial) is not
         # correctly serializable, we make it a list, as the underling
         # API expects this to be a list
         return list(status)
 
     @reraise_safe_exceptions
     def ctx_user(self, wire, revision):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         return ctx.user()
 
     @reraise_safe_exceptions
     def check_url(self, url, config):
         _proto = None
         if '+' in url[:url.find('://')]:
             _proto = url[0:url.find('+')]
             url = url[url.find('+') + 1:]
         handlers = []
         url_obj = url_parser(url)
         test_uri, authinfo = url_obj.authinfo()
         url_obj.passwd = '*****' if url_obj.passwd else url_obj.passwd
         url_obj.query = obfuscate_qs(url_obj.query)
 
         cleaned_uri = str(url_obj)
         log.info("Checking URL for remote cloning/import: %s", cleaned_uri)
 
         if authinfo:
             # create a password manager
             passmgr = urllib2.HTTPPasswordMgrWithDefaultRealm()
             passmgr.add_password(*authinfo)
 
             handlers.extend((httpbasicauthhandler(passmgr),
                              httpdigestauthhandler(passmgr)))
 
         o = urllib2.build_opener(*handlers)
         o.addheaders = [('Content-Type', 'application/mercurial-0.1'),
                         ('Accept', 'application/mercurial-0.1')]
 
         q = {"cmd": 'between'}
         q.update({'pairs': "%s-%s" % ('0' * 40, '0' * 40)})
         qs = '?%s' % urllib.urlencode(q)
         cu = "%s%s" % (test_uri, qs)
         req = urllib2.Request(cu, None, {})
 
         try:
             log.debug("Trying to open URL %s", cleaned_uri)
             resp = o.open(req)
             if resp.code != 200:
                 raise exceptions.URLError()('Return Code is not 200')
         except Exception as e:
             log.warning("URL cannot be opened: %s", cleaned_uri, exc_info=True)
             # means it cannot be cloned
             raise exceptions.URLError(e)("[%s] org_exc: %s" % (cleaned_uri, e))
 
         # now check if it's a proper hg repo, but don't do it for svn
         try:
             if _proto == 'svn':
                 pass
             else:
                 # check for pure hg repos
                 log.debug(
                     "Verifying if URL is a Mercurial repository: %s",
                     cleaned_uri)
                 ui = make_ui_from_config(config)
                 peer_checker = makepeer(ui, url)
                 peer_checker.lookup('tip')
         except Exception as e:
             log.warning("URL is not a valid Mercurial repository: %s",
                         cleaned_uri)
             raise exceptions.URLError(e)(
                 "url [%s] does not look like an hg repo org_exc: %s"
                 % (cleaned_uri, e))
 
         log.info("URL is a valid Mercurial repository: %s", cleaned_uri)
         return True
 
     @reraise_safe_exceptions
     def diff(self, wire, commit_id_1, commit_id_2, file_filter, opt_git, opt_ignorews, context):
         repo = self._factory.repo(wire)
 
         if file_filter:
             match_filter = match(file_filter[0], '', [file_filter[1]])
         else:
             match_filter = file_filter
         opts = diffopts(git=opt_git, ignorews=opt_ignorews, context=context, showfunc=1)
 
         try:
             return "".join(patch.diff(
                 repo, node1=commit_id_1, node2=commit_id_2, match=match_filter, opts=opts))
         except RepoLookupError as e:
             raise exceptions.LookupException(e)()
 
     @reraise_safe_exceptions
     def node_history(self, wire, revision, path, limit):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _node_history(_context_uid, _repo_id, _revision, _path, _limit):
             repo = self._factory.repo(wire)
 
             ctx = self._get_ctx(repo, revision)
             fctx = ctx.filectx(path)
 
             def history_iter():
                 limit_rev = fctx.rev()
                 for obj in reversed(list(fctx.filelog())):
                     obj = fctx.filectx(obj)
                     ctx = obj.changectx()
                     if ctx.hidden() or ctx.obsolete():
                         continue
 
                     if limit_rev >= obj.rev():
                         yield obj
 
             history = []
             for cnt, obj in enumerate(history_iter()):
                 if limit and cnt >= limit:
                     break
                 history.append(hex(obj.node()))
 
             return [x for x in history]
         return _node_history(context_uid, repo_id, revision, path, limit)
 
     @reraise_safe_exceptions
     def node_history_untill(self, wire, revision, path, limit):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _node_history_until(_context_uid, _repo_id):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, revision)
             fctx = ctx.filectx(path)
 
             file_log = list(fctx.filelog())
             if limit:
                 # Limit to the last n items
                 file_log = file_log[-limit:]
 
             return [hex(fctx.filectx(cs).node()) for cs in reversed(file_log)]
         return _node_history_until(context_uid, repo_id, revision, path, limit)
 
     @reraise_safe_exceptions
     def fctx_annotate(self, wire, revision, path):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         fctx = ctx.filectx(path)
 
         result = []
         for i, annotate_obj in enumerate(fctx.annotate(), 1):
             ln_no = i
             sha = hex(annotate_obj.fctx.node())
             content = annotate_obj.text
             result.append((ln_no, sha, content))
         return result
 
     @reraise_safe_exceptions
     def fctx_node_data(self, wire, revision, path):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         fctx = ctx.filectx(path)
         return fctx.data()
 
     @reraise_safe_exceptions
     def fctx_flags(self, wire, commit_id, path):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _fctx_flags(_repo_id, _commit_id, _path):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             fctx = ctx.filectx(path)
             return fctx.flags()
 
         return _fctx_flags(repo_id, commit_id, path)
 
     @reraise_safe_exceptions
     def fctx_size(self, wire, commit_id, path):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _fctx_size(_repo_id, _revision, _path):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, commit_id)
             fctx = ctx.filectx(path)
             return fctx.size()
         return _fctx_size(repo_id, commit_id, path)
 
     @reraise_safe_exceptions
     def get_all_commit_ids(self, wire, name):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_all_commit_ids(_context_uid, _repo_id, _name):
             repo = self._factory.repo(wire)
             repo = repo.filtered(name)
             revs = map(lambda x: hex(x[7]), repo.changelog.index)
             return revs
         return _get_all_commit_ids(context_uid, repo_id, name)
 
     @reraise_safe_exceptions
     def get_config_value(self, wire, section, name, untrusted=False):
         repo = self._factory.repo(wire)
         return repo.ui.config(section, name, untrusted=untrusted)
 
     @reraise_safe_exceptions
     def is_large_file(self, wire, commit_id, path):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _is_large_file(_context_uid, _repo_id, _commit_id, _path):
             return largefiles.lfutil.isstandin(path)
 
         return _is_large_file(context_uid, repo_id, commit_id, path)
 
     @reraise_safe_exceptions
     def is_binary(self, wire, revision, path):
         cache_on, context_uid, repo_id = self._cache_on(wire)
 
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _is_binary(_repo_id, _sha, _path):
             repo = self._factory.repo(wire)
             ctx = self._get_ctx(repo, revision)
             fctx = ctx.filectx(path)
             return fctx.isbinary()
 
         return _is_binary(repo_id, revision, path)
 
     @reraise_safe_exceptions
     def in_largefiles_store(self, wire, sha):
         repo = self._factory.repo(wire)
         return largefiles.lfutil.instore(repo, sha)
 
     @reraise_safe_exceptions
     def in_user_cache(self, wire, sha):
         repo = self._factory.repo(wire)
         return largefiles.lfutil.inusercache(repo.ui, sha)
 
     @reraise_safe_exceptions
     def store_path(self, wire, sha):
         repo = self._factory.repo(wire)
         return largefiles.lfutil.storepath(repo, sha)
 
     @reraise_safe_exceptions
     def link(self, wire, sha, path):
         repo = self._factory.repo(wire)
         largefiles.lfutil.link(
             largefiles.lfutil.usercachepath(repo.ui, sha), path)
 
     @reraise_safe_exceptions
     def localrepository(self, wire, create=False):
         self._factory.repo(wire, create=create)
 
     @reraise_safe_exceptions
     def lookup(self, wire, revision, both):
         cache_on, context_uid, repo_id = self._cache_on(wire)
 
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _lookup(_context_uid, _repo_id, _revision, _both):
 
             repo = self._factory.repo(wire)
             rev = _revision
             if isinstance(rev, int):
                 # NOTE(marcink):
                 # since Mercurial doesn't support negative indexes properly
                 # we need to shift accordingly by one to get proper index, e.g
                 # repo[-1] => repo[-2]
                 # repo[0]  => repo[-1]
                 if rev <= 0:
                     rev = rev + -1
             try:
                 ctx = self._get_ctx(repo, rev)
             except (TypeError, RepoLookupError) as e:
                 e._org_exc_tb = traceback.format_exc()
                 raise exceptions.LookupException(e)(rev)
             except LookupError as e:
                 e._org_exc_tb = traceback.format_exc()
                 raise exceptions.LookupException(e)(e.name)
 
             if not both:
                 return ctx.hex()
 
             ctx = repo[ctx.hex()]
             return ctx.hex(), ctx.rev()
 
         return _lookup(context_uid, repo_id, revision, both)
 
     @reraise_safe_exceptions
     def sync_push(self, wire, url):
         if not self.check_url(url, wire['config']):
             return
 
         repo = self._factory.repo(wire)
 
         # Disable any prompts for this repo
         repo.ui.setconfig('ui', 'interactive', 'off', '-y')
 
         bookmarks = dict(repo._bookmarks).keys()
         remote = peer(repo, {}, url)
         # Disable any prompts for this remote
         remote.ui.setconfig('ui', 'interactive', 'off', '-y')
 
         return exchange.push(
             repo, remote, newbranch=True, bookmarks=bookmarks).cgresult
 
     @reraise_safe_exceptions
     def revision(self, wire, rev):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, rev)
         return ctx.rev()
 
     @reraise_safe_exceptions
     def rev_range(self, wire, commit_filter):
         cache_on, context_uid, repo_id = self._cache_on(wire)
 
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _rev_range(_context_uid, _repo_id, _filter):
             repo = self._factory.repo(wire)
             revisions = [rev for rev in revrange(repo, commit_filter)]
             return revisions
 
         return _rev_range(context_uid, repo_id, sorted(commit_filter))
 
     @reraise_safe_exceptions
     def rev_range_hash(self, wire, node):
         repo = self._factory.repo(wire)
 
         def get_revs(repo, rev_opt):
             if rev_opt:
                 revs = revrange(repo, rev_opt)
                 if len(revs) == 0:
                     return (nullrev, nullrev)
                 return max(revs), min(revs)
             else:
                 return len(repo) - 1, 0
 
         stop, start = get_revs(repo, [node + ':'])
         revs = [hex(repo[r].node()) for r in xrange(start, stop + 1)]
         return revs
 
     @reraise_safe_exceptions
     def revs_from_revspec(self, wire, rev_spec, *args, **kwargs):
         other_path = kwargs.pop('other_path', None)
 
         # case when we want to compare two independent repositories
         if other_path and other_path != wire["path"]:
             baseui = self._factory._create_config(wire["config"])
             repo = unionrepo.makeunionrepository(baseui, other_path, wire["path"])
         else:
             repo = self._factory.repo(wire)
         return list(repo.revs(rev_spec, *args))
 
     @reraise_safe_exceptions
     def verify(self, wire,):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
 
         baseui, output = patch_ui_message_output(baseui)
 
         repo.ui = baseui
         verify.verify(repo)
         return output.getvalue()
 
     @reraise_safe_exceptions
     def hg_update_cache(self, wire,):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         baseui, output = patch_ui_message_output(baseui)
 
         repo.ui = baseui
         with repo.wlock(), repo.lock():
             repo.updatecaches(full=True)
 
         return output.getvalue()
 
     @reraise_safe_exceptions
     def hg_rebuild_fn_cache(self, wire,):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         baseui, output = patch_ui_message_output(baseui)
 
         repo.ui = baseui
 
         repair.rebuildfncache(baseui, repo)
 
         return output.getvalue()
 
     @reraise_safe_exceptions
     def tags(self, wire):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _tags(_context_uid, _repo_id):
             repo = self._factory.repo(wire)
             return repo.tags()
 
         return _tags(context_uid, repo_id)
 
     @reraise_safe_exceptions
     def update(self, wire, node=None, clean=False):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         commands.update(baseui, repo, node=node, clean=clean)
 
     @reraise_safe_exceptions
     def identify(self, wire):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         output = io.BytesIO()
         baseui.write = output.write
         # This is required to get a full node id
         baseui.debugflag = True
         commands.identify(baseui, repo, id=True)
 
         return output.getvalue()
 
     @reraise_safe_exceptions
     def heads(self, wire, branch=None):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         output = io.BytesIO()
 
         def write(data, **unused_kwargs):
             output.write(data)
 
         baseui.write = write
         if branch:
             args = [branch]
         else:
             args = []
         commands.heads(baseui, repo, template='{node} ', *args)
 
         return output.getvalue()
 
     @reraise_safe_exceptions
     def ancestor(self, wire, revision1, revision2):
         repo = self._factory.repo(wire)
         changelog = repo.changelog
         lookup = repo.lookup
         a = changelog.ancestor(lookup(revision1), lookup(revision2))
         return hex(a)
 
     @reraise_safe_exceptions
     def clone(self, wire, source, dest, update_after_clone=False, hooks=True):
         baseui = self._factory._create_config(wire["config"], hooks=hooks)
         clone(baseui, source, dest, noupdate=not update_after_clone)
 
     @reraise_safe_exceptions
     def commitctx(self, wire, message, parents, commit_time, commit_timezone, user, files, extra, removed, updated):
 
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         publishing = baseui.configbool('phases', 'publish')
         if publishing:
             new_commit = 'public'
         else:
             new_commit = 'draft'
 
         def _filectxfn(_repo, ctx, path):
             """
             Marks given path as added/changed/removed in a given _repo. This is
             for internal mercurial commit function.
             """
 
             # check if this path is removed
             if path in removed:
                 # returning None is a way to mark node for removal
                 return None
 
             # check if this path is added
             for node in updated:
                 if node['path'] == path:
                     return memfilectx(
                         _repo,
                         changectx=ctx,
                         path=node['path'],
                         data=node['content'],
                         islink=False,
                         isexec=bool(node['mode'] & stat.S_IXUSR),
                         copysource=False)
 
             raise exceptions.AbortException()(
                 "Given path haven't been marked as added, "
                 "changed or removed (%s)" % path)
 
         with repo.ui.configoverride({('phases', 'new-commit'): new_commit}):
 
             commit_ctx = memctx(
                 repo=repo,
                 parents=parents,
                 text=message,
                 files=files,
                 filectxfn=_filectxfn,
                 user=user,
                 date=(commit_time, commit_timezone),
                 extra=extra)
 
             n = repo.commitctx(commit_ctx)
             new_id = hex(n)
 
             return new_id
 
     @reraise_safe_exceptions
     def pull(self, wire, url, commit_ids=None):
         repo = self._factory.repo(wire)
         # Disable any prompts for this repo
         repo.ui.setconfig('ui', 'interactive', 'off', '-y')
 
         remote = peer(repo, {}, url)
         # Disable any prompts for this remote
         remote.ui.setconfig('ui', 'interactive', 'off', '-y')
 
         if commit_ids:
             commit_ids = [bin(commit_id) for commit_id in commit_ids]
 
         return exchange.pull(
             repo, remote, heads=commit_ids, force=None).cgresult
 
     @reraise_safe_exceptions
     def pull_cmd(self, wire, source, bookmark=None, branch=None, revision=None, hooks=True):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'], hooks=hooks)
 
         # Mercurial internally has a lot of logic that checks ONLY if
         # option is defined, we just pass those if they are defined then
         opts = {}
         if bookmark:
             opts['bookmark'] = bookmark
         if branch:
             opts['branch'] = branch
         if revision:
             opts['rev'] = revision
 
         commands.pull(baseui, repo, source, **opts)
 
     @reraise_safe_exceptions
     def push(self, wire, revisions, dest_path, hooks=True, push_branches=False):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'], hooks=hooks)
         commands.push(baseui, repo, dest=dest_path, rev=revisions,
                       new_branch=push_branches)
 
     @reraise_safe_exceptions
     def strip(self, wire, revision, update, backup):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         hgext_strip(
             repo.baseui, repo, ctx.node(), update=update, backup=backup)
 
     @reraise_safe_exceptions
     def get_unresolved_files(self, wire):
         repo = self._factory.repo(wire)
 
         log.debug('Calculating unresolved files for repo: %s', repo)
         output = io.BytesIO()
 
         def write(data, **unused_kwargs):
             output.write(data)
 
         baseui = self._factory._create_config(wire['config'])
         baseui.write = write
 
         commands.resolve(baseui, repo, list=True)
         unresolved = output.getvalue().splitlines(0)
         return unresolved
 
     @reraise_safe_exceptions
     def merge(self, wire, revision):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         repo.ui.setconfig('ui', 'merge', 'internal:dump')
 
         # In case of sub repositories are used mercurial prompts the user in
         # case of merge conflicts or different sub repository sources. By
         # setting the interactive flag to `False` mercurial doesn't prompt the
         # used but instead uses a default value.
         repo.ui.setconfig('ui', 'interactive', False)
         commands.merge(baseui, repo, rev=revision)
 
     @reraise_safe_exceptions
     def merge_state(self, wire):
         repo = self._factory.repo(wire)
         repo.ui.setconfig('ui', 'merge', 'internal:dump')
 
         # In case of sub repositories are used mercurial prompts the user in
         # case of merge conflicts or different sub repository sources. By
         # setting the interactive flag to `False` mercurial doesn't prompt the
         # used but instead uses a default value.
         repo.ui.setconfig('ui', 'interactive', False)
         ms = hg_merge.mergestate(repo)
         return [x for x in ms.unresolved()]
 
     @reraise_safe_exceptions
     def commit(self, wire, message, username, close_branch=False):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         repo.ui.setconfig('ui', 'username', username)
         commands.commit(baseui, repo, message=message, close_branch=close_branch)
 
     @reraise_safe_exceptions
     def rebase(self, wire, source=None, dest=None, abort=False):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         repo.ui.setconfig('ui', 'merge', 'internal:dump')
         # In case of sub repositories are used mercurial prompts the user in
         # case of merge conflicts or different sub repository sources. By
         # setting the interactive flag to `False` mercurial doesn't prompt the
         # used but instead uses a default value.
         repo.ui.setconfig('ui', 'interactive', False)
         rebase.rebase(baseui, repo, base=source, dest=dest, abort=abort, keep=not abort)
 
     @reraise_safe_exceptions
     def tag(self, wire, name, revision, message, local, user, tag_time, tag_timezone):
         repo = self._factory.repo(wire)
         ctx = self._get_ctx(repo, revision)
         node = ctx.node()
 
         date = (tag_time, tag_timezone)
         try:
             hg_tag.tag(repo, name, node, message, local, user, date)
         except Abort as e:
             log.exception("Tag operation aborted")
             # Exception can contain unicode which we convert
             raise exceptions.AbortException(e)(repr(e))
 
     @reraise_safe_exceptions
     def bookmark(self, wire, bookmark, revision=None):
         repo = self._factory.repo(wire)
         baseui = self._factory._create_config(wire['config'])
         commands.bookmark(baseui, repo, bookmark, rev=revision, force=True)
 
     @reraise_safe_exceptions
     def install_hooks(self, wire, force=False):
         # we don't need any special hooks for Mercurial
         pass
 
     @reraise_safe_exceptions
     def get_hooks_info(self, wire):
         return {
             'pre_version': vcsserver.__version__,
             'post_version': vcsserver.__version__,
         }
 
     @reraise_safe_exceptions
+    def set_head_ref(self, wire, head_name):
+        pass
+
+    @reraise_safe_exceptions
     def archive_repo(self, wire, archive_dest_path, kind, mtime, archive_at_path,
                      archive_dir_name, commit_id):
 
         def file_walker(_commit_id, path):
             repo = self._factory.repo(wire)
             ctx = repo[_commit_id]
             is_root = path in ['', '/']
             if is_root:
                 matcher = alwaysmatcher(badfn=None)
             else:
                 matcher = patternmatcher('', [(b'glob', path+'/**', b'')], badfn=None)
             file_iter = ctx.manifest().walk(matcher)
 
             for fn in file_iter:
                 file_path = fn
                 flags = ctx.flags(fn)
                 mode = b'x' in flags and 0o755 or 0o644
                 is_link = b'l' in flags
 
                 yield ArchiveNode(file_path, mode, is_link, ctx[fn].data)
 
         return archive_repo(file_walker, archive_dest_path, kind, mtime, archive_at_path,
                             archive_dir_name, commit_id)
 

vcsserver/svn.py

@@ -1,862 +1,866 b''
 # RhodeCode VCSServer provides access to different vcs backends via network.
 # Copyright (C) 2014-2020 RhodeCode GmbH
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation; either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software Foundation,
 # Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 
 from __future__ import absolute_import
 
 import os
 import subprocess
 import time
 from urllib2 import URLError
 import urlparse
 import logging
 import posixpath as vcspath
 import StringIO
 import urllib
 import traceback
 
 import svn.client
 import svn.core
 import svn.delta
 import svn.diff
 import svn.fs
 import svn.repos
 
 from vcsserver import svn_diff, exceptions, subprocessio, settings
 from vcsserver.base import RepoFactory, raise_from_original, ArchiveNode, archive_repo
 from vcsserver.exceptions import NoContentException
 from vcsserver.utils import safe_str
 from vcsserver.vcs_base import RemoteBase
 
 log = logging.getLogger(__name__)
 
 
 svn_compatible_versions_map = {
     'pre-1.4-compatible': '1.3',
     'pre-1.5-compatible': '1.4',
     'pre-1.6-compatible': '1.5',
     'pre-1.8-compatible': '1.7',
     'pre-1.9-compatible': '1.8',
 }
 
 current_compatible_version = '1.12'
 
 
 def reraise_safe_exceptions(func):
     """Decorator for converting svn exceptions to something neutral."""
     def wrapper(*args, **kwargs):
         try:
             return func(*args, **kwargs)
         except Exception as e:
             if not hasattr(e, '_vcs_kind'):
                 log.exception("Unhandled exception in svn remote call")
                 raise_from_original(exceptions.UnhandledException(e))
             raise
     return wrapper
 
 
 class SubversionFactory(RepoFactory):
     repo_type = 'svn'
 
     def _create_repo(self, wire, create, compatible_version):
         path = svn.core.svn_path_canonicalize(wire['path'])
         if create:
             fs_config = {'compatible-version': current_compatible_version}
             if compatible_version:
 
                 compatible_version_string = \
                     svn_compatible_versions_map.get(compatible_version) \
                     or compatible_version
                 fs_config['compatible-version'] = compatible_version_string
 
             log.debug('Create SVN repo with config "%s"', fs_config)
             repo = svn.repos.create(path, "", "", None, fs_config)
         else:
             repo = svn.repos.open(path)
 
         log.debug('Got SVN object: %s', repo)
         return repo
 
     def repo(self, wire, create=False, compatible_version=None):
         """
         Get a repository instance for the given path.
         """
         return self._create_repo(wire, create, compatible_version)
 
 
 NODE_TYPE_MAPPING = {
     svn.core.svn_node_file: 'file',
     svn.core.svn_node_dir: 'dir',
 }
 
 
 class SvnRemote(RemoteBase):
 
     def __init__(self, factory, hg_factory=None):
         self._factory = factory
         # TODO: Remove once we do not use internal Mercurial objects anymore
         # for subversion
         self._hg_factory = hg_factory
 
     @reraise_safe_exceptions
     def discover_svn_version(self):
         try:
             import svn.core
             svn_ver = svn.core.SVN_VERSION
         except ImportError:
             svn_ver = None
         return svn_ver
 
     @reraise_safe_exceptions
     def is_empty(self, wire):
 
         try:
             return self.lookup(wire, -1) == 0
         except Exception:
             log.exception("failed to read object_store")
             return False
 
     def check_url(self, url, config_items):
         # this can throw exception if not installed, but we detect this
         from hgsubversion import svnrepo
 
         baseui = self._hg_factory._create_config(config_items)
         # uuid function get's only valid UUID from proper repo, else
         # throws exception
         try:
             svnrepo.svnremoterepo(baseui, url).svn.uuid
         except Exception:
             tb = traceback.format_exc()
             log.debug("Invalid Subversion url: `%s`, tb: %s", url, tb)
             raise URLError(
                 '"%s" is not a valid Subversion source url.' % (url, ))
         return True
 
     def is_path_valid_repository(self, wire, path):
 
         # NOTE(marcink):  short circuit the check for SVN repo
         # the repos.open might be expensive to check, but we have one cheap
         # pre condition that we can use, to check for 'format' file
 
         if not os.path.isfile(os.path.join(path, 'format')):
             return False
 
         try:
             svn.repos.open(path)
         except svn.core.SubversionException:
             tb = traceback.format_exc()
             log.debug("Invalid Subversion path `%s`, tb: %s", path, tb)
             return False
         return True
 
     @reraise_safe_exceptions
     def verify(self, wire,):
         repo_path = wire['path']
         if not self.is_path_valid_repository(wire, repo_path):
             raise Exception(
                 "Path %s is not a valid Subversion repository." % repo_path)
 
         cmd = ['svnadmin', 'info', repo_path]
         stdout, stderr = subprocessio.run_command(cmd)
         return stdout
 
     def lookup(self, wire, revision):
         if revision not in [-1, None, 'HEAD']:
             raise NotImplementedError
         repo = self._factory.repo(wire)
         fs_ptr = svn.repos.fs(repo)
         head = svn.fs.youngest_rev(fs_ptr)
         return head
 
     def lookup_interval(self, wire, start_ts, end_ts):
         repo = self._factory.repo(wire)
         fsobj = svn.repos.fs(repo)
         start_rev = None
         end_rev = None
         if start_ts:
             start_ts_svn = apr_time_t(start_ts)
             start_rev = svn.repos.dated_revision(repo, start_ts_svn) + 1
         else:
             start_rev = 1
         if end_ts:
             end_ts_svn = apr_time_t(end_ts)
             end_rev = svn.repos.dated_revision(repo, end_ts_svn)
         else:
             end_rev = svn.fs.youngest_rev(fsobj)
         return start_rev, end_rev
 
     def revision_properties(self, wire, revision):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _revision_properties(_repo_id, _revision):
             repo = self._factory.repo(wire)
             fs_ptr = svn.repos.fs(repo)
             return svn.fs.revision_proplist(fs_ptr, revision)
         return _revision_properties(repo_id, revision)
 
     def revision_changes(self, wire, revision):
 
         repo = self._factory.repo(wire)
         fsobj = svn.repos.fs(repo)
         rev_root = svn.fs.revision_root(fsobj, revision)
 
         editor = svn.repos.ChangeCollector(fsobj, rev_root)
         editor_ptr, editor_baton = svn.delta.make_editor(editor)
         base_dir = ""
         send_deltas = False
         svn.repos.replay2(
             rev_root, base_dir, svn.core.SVN_INVALID_REVNUM, send_deltas,
             editor_ptr, editor_baton, None)
 
         added = []
         changed = []
         removed = []
 
         # TODO: CHANGE_ACTION_REPLACE: Figure out where it belongs
         for path, change in editor.changes.iteritems():
             # TODO: Decide what to do with directory nodes. Subversion can add
             # empty directories.
 
             if change.item_kind == svn.core.svn_node_dir:
                 continue
             if change.action in [svn.repos.CHANGE_ACTION_ADD]:
                 added.append(path)
             elif change.action in [svn.repos.CHANGE_ACTION_MODIFY,
                                    svn.repos.CHANGE_ACTION_REPLACE]:
                 changed.append(path)
             elif change.action in [svn.repos.CHANGE_ACTION_DELETE]:
                 removed.append(path)
             else:
                 raise NotImplementedError(
                     "Action %s not supported on path %s" % (
                         change.action, path))
 
         changes = {
             'added': added,
             'changed': changed,
             'removed': removed,
         }
         return changes
 
     @reraise_safe_exceptions
     def node_history(self, wire, path, revision, limit):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _assert_correct_path(_context_uid, _repo_id, _path, _revision, _limit):
             cross_copies = False
             repo = self._factory.repo(wire)
             fsobj = svn.repos.fs(repo)
             rev_root = svn.fs.revision_root(fsobj, revision)
 
             history_revisions = []
             history = svn.fs.node_history(rev_root, path)
             history = svn.fs.history_prev(history, cross_copies)
             while history:
                 __, node_revision = svn.fs.history_location(history)
                 history_revisions.append(node_revision)
                 if limit and len(history_revisions) >= limit:
                     break
                 history = svn.fs.history_prev(history, cross_copies)
             return history_revisions
         return _assert_correct_path(context_uid, repo_id, path, revision, limit)
 
     def node_properties(self, wire, path, revision):
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _node_properties(_repo_id, _path, _revision):
             repo = self._factory.repo(wire)
             fsobj = svn.repos.fs(repo)
             rev_root = svn.fs.revision_root(fsobj, revision)
             return svn.fs.node_proplist(rev_root, path)
         return _node_properties(repo_id, path, revision)
 
     def file_annotate(self, wire, path, revision):
         abs_path = 'file://' + urllib.pathname2url(
             vcspath.join(wire['path'], path))
         file_uri = svn.core.svn_path_canonicalize(abs_path)
 
         start_rev = svn_opt_revision_value_t(0)
         peg_rev = svn_opt_revision_value_t(revision)
         end_rev = peg_rev
 
         annotations = []
 
         def receiver(line_no, revision, author, date, line, pool):
             annotations.append((line_no, revision, line))
 
         # TODO: Cannot use blame5, missing typemap function in the swig code
         try:
             svn.client.blame2(
                 file_uri, peg_rev, start_rev, end_rev,
                 receiver, svn.client.create_context())
         except svn.core.SubversionException as exc:
             log.exception("Error during blame operation.")
             raise Exception(
                 "Blame not supported or file does not exist at path %s. "
                 "Error %s." % (path, exc))
 
         return annotations
 
     def get_node_type(self, wire, path, revision=None):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_node_type(_repo_id, _path, _revision):
             repo = self._factory.repo(wire)
             fs_ptr = svn.repos.fs(repo)
             if _revision is None:
                 _revision = svn.fs.youngest_rev(fs_ptr)
             root = svn.fs.revision_root(fs_ptr, _revision)
             node = svn.fs.check_path(root, path)
             return NODE_TYPE_MAPPING.get(node, None)
         return _get_node_type(repo_id, path, revision)
 
     def get_nodes(self, wire, path, revision=None):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_nodes(_repo_id, _path, _revision):
             repo = self._factory.repo(wire)
             fsobj = svn.repos.fs(repo)
             if _revision is None:
                 _revision = svn.fs.youngest_rev(fsobj)
             root = svn.fs.revision_root(fsobj, _revision)
             entries = svn.fs.dir_entries(root, path)
             result = []
             for entry_path, entry_info in entries.iteritems():
                 result.append(
                     (entry_path, NODE_TYPE_MAPPING.get(entry_info.kind, None)))
             return result
         return _get_nodes(repo_id, path, revision)
 
     def get_file_content(self, wire, path, rev=None):
         repo = self._factory.repo(wire)
         fsobj = svn.repos.fs(repo)
         if rev is None:
             rev = svn.fs.youngest_revision(fsobj)
         root = svn.fs.revision_root(fsobj, rev)
         content = svn.core.Stream(svn.fs.file_contents(root, path))
         return content.read()
 
     def get_file_size(self, wire, path, revision=None):
 
         cache_on, context_uid, repo_id = self._cache_on(wire)
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _get_file_size(_repo_id, _path, _revision):
             repo = self._factory.repo(wire)
             fsobj = svn.repos.fs(repo)
             if _revision is None:
                 _revision = svn.fs.youngest_revision(fsobj)
             root = svn.fs.revision_root(fsobj, _revision)
             size = svn.fs.file_length(root, path)
             return size
         return _get_file_size(repo_id, path, revision)
 
     def create_repository(self, wire, compatible_version=None):
         log.info('Creating Subversion repository in path "%s"', wire['path'])
         self._factory.repo(wire, create=True,
                            compatible_version=compatible_version)
 
     def get_url_and_credentials(self, src_url):
         obj = urlparse.urlparse(src_url)
         username = obj.username or None
         password = obj.password or None
         return username, password, src_url
 
     def import_remote_repository(self, wire, src_url):
         repo_path = wire['path']
         if not self.is_path_valid_repository(wire, repo_path):
             raise Exception(
                 "Path %s is not a valid Subversion repository." % repo_path)
 
         username, password, src_url = self.get_url_and_credentials(src_url)
         rdump_cmd = ['svnrdump', 'dump', '--non-interactive',
                      '--trust-server-cert-failures=unknown-ca']
         if username and password:
             rdump_cmd += ['--username', username, '--password', password]
         rdump_cmd += [src_url]
 
         rdump = subprocess.Popen(
             rdump_cmd,
             stdout=subprocess.PIPE, stderr=subprocess.PIPE)
         load = subprocess.Popen(
             ['svnadmin', 'load', repo_path], stdin=rdump.stdout)
 
         # TODO: johbo: This can be a very long operation, might be better
         # to track some kind of status and provide an api to check if the
         # import is done.
         rdump.wait()
         load.wait()
 
         log.debug('Return process ended with code: %s', rdump.returncode)
         if rdump.returncode != 0:
             errors = rdump.stderr.read()
             log.error('svnrdump dump failed: statuscode %s: message: %s',
                       rdump.returncode, errors)
             reason = 'UNKNOWN'
             if 'svnrdump: E230001:' in errors:
                 reason = 'INVALID_CERTIFICATE'
 
             if reason == 'UNKNOWN':
                 reason = 'UNKNOWN:{}'.format(errors)
             raise Exception(
                 'Failed to dump the remote repository from %s. Reason:%s' % (
                     src_url, reason))
         if load.returncode != 0:
             raise Exception(
                 'Failed to load the dump of remote repository from %s.' %
                 (src_url, ))
 
     def commit(self, wire, message, author, timestamp, updated, removed):
         assert isinstance(message, str)
         assert isinstance(author, str)
 
         repo = self._factory.repo(wire)
         fsobj = svn.repos.fs(repo)
 
         rev = svn.fs.youngest_rev(fsobj)
         txn = svn.repos.fs_begin_txn_for_commit(repo, rev, author, message)
         txn_root = svn.fs.txn_root(txn)
 
         for node in updated:
             TxnNodeProcessor(node, txn_root).update()
         for node in removed:
             TxnNodeProcessor(node, txn_root).remove()
 
         commit_id = svn.repos.fs_commit_txn(repo, txn)
 
         if timestamp:
             apr_time = apr_time_t(timestamp)
             ts_formatted = svn.core.svn_time_to_cstring(apr_time)
             svn.fs.change_rev_prop(fsobj, commit_id, 'svn:date', ts_formatted)
 
         log.debug('Committed revision "%s" to "%s".', commit_id, wire['path'])
         return commit_id
 
     def diff(self, wire, rev1, rev2, path1=None, path2=None,
              ignore_whitespace=False, context=3):
 
         wire.update(cache=False)
         repo = self._factory.repo(wire)
         diff_creator = SvnDiffer(
             repo, rev1, path1, rev2, path2, ignore_whitespace, context)
         try:
             return diff_creator.generate_diff()
         except svn.core.SubversionException as e:
             log.exception(
                 "Error during diff operation operation. "
                 "Path might not exist %s, %s" % (path1, path2))
             return ""
 
     @reraise_safe_exceptions
     def is_large_file(self, wire, path):
         return False
 
     @reraise_safe_exceptions
     def is_binary(self, wire, rev, path):
         cache_on, context_uid, repo_id = self._cache_on(wire)
 
         region = self._region(wire)
         @region.conditional_cache_on_arguments(condition=cache_on)
         def _is_binary(_repo_id, _rev, _path):
             raw_bytes = self.get_file_content(wire, path, rev)
             return raw_bytes and '\0' in raw_bytes
 
         return _is_binary(repo_id, rev, path)
 
     @reraise_safe_exceptions
     def run_svn_command(self, wire, cmd, **opts):
         path = wire.get('path', None)
 
         if path and os.path.isdir(path):
             opts['cwd'] = path
 
         safe_call = opts.pop('_safe', False)
 
         svnenv = os.environ.copy()
         svnenv.update(opts.pop('extra_env', {}))
 
         _opts = {'env': svnenv, 'shell': False}
 
         try:
             _opts.update(opts)
             p = subprocessio.SubprocessIOChunker(cmd, **_opts)
 
             return ''.join(p), ''.join(p.error)
         except (EnvironmentError, OSError) as err:
             if safe_call:
                 return '', safe_str(err).strip()
             else:
                 cmd = ' '.join(cmd)  # human friendly CMD
                 tb_err = ("Couldn't run svn command (%s).\n"
                           "Original error was:%s\n"
                           "Call options:%s\n"
                           % (cmd, err, _opts))
                 log.exception(tb_err)
                 raise exceptions.VcsException()(tb_err)
 
     @reraise_safe_exceptions
     def install_hooks(self, wire, force=False):
         from vcsserver.hook_utils import install_svn_hooks
         repo_path = wire['path']
         binary_dir = settings.BINARY_DIR
         executable = None
         if binary_dir:
             executable = os.path.join(binary_dir, 'python')
         return install_svn_hooks(
             repo_path, executable=executable, force_create=force)
 
     @reraise_safe_exceptions
     def get_hooks_info(self, wire):
         from vcsserver.hook_utils import (
             get_svn_pre_hook_version, get_svn_post_hook_version)
         repo_path = wire['path']
         return {
             'pre_version': get_svn_pre_hook_version(repo_path),
             'post_version': get_svn_post_hook_version(repo_path),
         }
 
     @reraise_safe_exceptions
+    def set_head_ref(self, wire, head_name):
+        pass
+
+    @reraise_safe_exceptions
     def archive_repo(self, wire, archive_dest_path, kind, mtime, archive_at_path,
                      archive_dir_name, commit_id):
 
         def walk_tree(root, root_dir, _commit_id):
             """
             Special recursive svn repo walker
             """
 
             filemode_default = 0o100644
             filemode_executable = 0o100755
 
             file_iter = svn.fs.dir_entries(root, root_dir)
             for f_name in file_iter:
                 f_type = NODE_TYPE_MAPPING.get(file_iter[f_name].kind, None)
 
                 if f_type == 'dir':
                     # return only DIR, and then all entries in that dir
                     yield os.path.join(root_dir, f_name), {'mode': filemode_default}, f_type
                     new_root = os.path.join(root_dir, f_name)
                     for _f_name, _f_data, _f_type in walk_tree(root, new_root, _commit_id):
                         yield _f_name, _f_data, _f_type
                 else:
                     f_path = os.path.join(root_dir, f_name).rstrip('/')
                     prop_list = svn.fs.node_proplist(root, f_path)
 
                     f_mode = filemode_default
                     if prop_list.get('svn:executable'):
                         f_mode = filemode_executable
 
                     f_is_link = False
                     if prop_list.get('svn:special'):
                         f_is_link = True
 
                     data = {
                         'is_link': f_is_link,
                         'mode': f_mode,
                         'content_stream': svn.core.Stream(svn.fs.file_contents(root, f_path)).read
                     }
 
                     yield f_path, data, f_type
 
         def file_walker(_commit_id, path):
             repo = self._factory.repo(wire)
             root = svn.fs.revision_root(svn.repos.fs(repo), int(commit_id))
 
             def no_content():
                 raise NoContentException()
 
             for f_name, f_data, f_type in walk_tree(root, path, _commit_id):
                 file_path = f_name
 
                 if f_type == 'dir':
                     mode = f_data['mode']
                     yield ArchiveNode(file_path, mode, False, no_content)
                 else:
                     mode = f_data['mode']
                     is_link = f_data['is_link']
                     data_stream = f_data['content_stream']
                     yield ArchiveNode(file_path, mode, is_link, data_stream)
 
         return archive_repo(file_walker, archive_dest_path, kind, mtime, archive_at_path,
                             archive_dir_name, commit_id)
 
 
 class SvnDiffer(object):
     """
     Utility to create diffs based on difflib and the Subversion api
     """
 
     binary_content = False
 
     def __init__(
             self, repo, src_rev, src_path, tgt_rev, tgt_path,
             ignore_whitespace, context):
         self.repo = repo
         self.ignore_whitespace = ignore_whitespace
         self.context = context
 
         fsobj = svn.repos.fs(repo)
 
         self.tgt_rev = tgt_rev
         self.tgt_path = tgt_path or ''
         self.tgt_root = svn.fs.revision_root(fsobj, tgt_rev)
         self.tgt_kind = svn.fs.check_path(self.tgt_root, self.tgt_path)
 
         self.src_rev = src_rev
         self.src_path = src_path or self.tgt_path
         self.src_root = svn.fs.revision_root(fsobj, src_rev)
         self.src_kind = svn.fs.check_path(self.src_root, self.src_path)
 
         self._validate()
 
     def _validate(self):
         if (self.tgt_kind != svn.core.svn_node_none and
                 self.src_kind != svn.core.svn_node_none and
                 self.src_kind != self.tgt_kind):
             # TODO: johbo: proper error handling
             raise Exception(
                 "Source and target are not compatible for diff generation. "
                 "Source type: %s, target type: %s" %
                 (self.src_kind, self.tgt_kind))
 
     def generate_diff(self):
         buf = StringIO.StringIO()
         if self.tgt_kind == svn.core.svn_node_dir:
             self._generate_dir_diff(buf)
         else:
             self._generate_file_diff(buf)
         return buf.getvalue()
 
     def _generate_dir_diff(self, buf):
         editor = DiffChangeEditor()
         editor_ptr, editor_baton = svn.delta.make_editor(editor)
         svn.repos.dir_delta2(
             self.src_root,
             self.src_path,
             '',  # src_entry
             self.tgt_root,
             self.tgt_path,
             editor_ptr, editor_baton,
             authorization_callback_allow_all,
             False,  # text_deltas
             svn.core.svn_depth_infinity,  # depth
             False,  # entry_props
             False,  # ignore_ancestry
         )
 
         for path, __, change in sorted(editor.changes):
             self._generate_node_diff(
                 buf, change, path, self.tgt_path, path, self.src_path)
 
     def _generate_file_diff(self, buf):
         change = None
         if self.src_kind == svn.core.svn_node_none:
             change = "add"
         elif self.tgt_kind == svn.core.svn_node_none:
             change = "delete"
         tgt_base, tgt_path = vcspath.split(self.tgt_path)
         src_base, src_path = vcspath.split(self.src_path)
         self._generate_node_diff(
             buf, change, tgt_path, tgt_base, src_path, src_base)
 
     def _generate_node_diff(
             self, buf, change, tgt_path, tgt_base, src_path, src_base):
 
         if self.src_rev == self.tgt_rev and tgt_base == src_base:
             # makes consistent behaviour with git/hg to return empty diff if
             # we compare same revisions
             return
 
         tgt_full_path = vcspath.join(tgt_base, tgt_path)
         src_full_path = vcspath.join(src_base, src_path)
 
         self.binary_content = False
         mime_type = self._get_mime_type(tgt_full_path)
 
         if mime_type and not mime_type.startswith('text'):
             self.binary_content = True
             buf.write("=" * 67 + '\n')
             buf.write("Cannot display: file marked as a binary type.\n")
             buf.write("svn:mime-type = %s\n" % mime_type)
         buf.write("Index: %s\n" % (tgt_path, ))
         buf.write("=" * 67 + '\n')
         buf.write("diff --git a/%(tgt_path)s b/%(tgt_path)s\n" % {
             'tgt_path': tgt_path})
 
         if change == 'add':
             # TODO: johbo: SVN is missing a zero here compared to git
             buf.write("new file mode 10644\n")
 
             #TODO(marcink): intro to binary detection of svn patches
             # if self.binary_content:
             #     buf.write('GIT binary patch\n')
 
             buf.write("--- /dev/null\t(revision 0)\n")
             src_lines = []
         else:
             if change == 'delete':
                 buf.write("deleted file mode 10644\n")
 
             #TODO(marcink): intro to binary detection of svn patches
             # if self.binary_content:
             #     buf.write('GIT binary patch\n')
 
             buf.write("--- a/%s\t(revision %s)\n" % (
                 src_path, self.src_rev))
             src_lines = self._svn_readlines(self.src_root, src_full_path)
 
         if change == 'delete':
             buf.write("+++ /dev/null\t(revision %s)\n" % (self.tgt_rev, ))
             tgt_lines = []
         else:
             buf.write("+++ b/%s\t(revision %s)\n" % (
                 tgt_path, self.tgt_rev))
             tgt_lines = self._svn_readlines(self.tgt_root, tgt_full_path)
 
         if not self.binary_content:
             udiff = svn_diff.unified_diff(
                 src_lines, tgt_lines, context=self.context,
                 ignore_blank_lines=self.ignore_whitespace,
                 ignore_case=False,
                 ignore_space_changes=self.ignore_whitespace)
             buf.writelines(udiff)
 
     def _get_mime_type(self, path):
         try:
             mime_type = svn.fs.node_prop(
                 self.tgt_root, path, svn.core.SVN_PROP_MIME_TYPE)
         except svn.core.SubversionException:
             mime_type = svn.fs.node_prop(
                 self.src_root, path, svn.core.SVN_PROP_MIME_TYPE)
         return mime_type
 
     def _svn_readlines(self, fs_root, node_path):
         if self.binary_content:
             return []
         node_kind = svn.fs.check_path(fs_root, node_path)
         if node_kind not in (
                 svn.core.svn_node_file, svn.core.svn_node_symlink):
             return []
         content = svn.core.Stream(svn.fs.file_contents(fs_root, node_path)).read()
         return content.splitlines(True)
 
 
 class DiffChangeEditor(svn.delta.Editor):
     """
     Records changes between two given revisions
     """
 
     def __init__(self):
         self.changes = []
 
     def delete_entry(self, path, revision, parent_baton, pool=None):
         self.changes.append((path, None, 'delete'))
 
     def add_file(
             self, path, parent_baton, copyfrom_path, copyfrom_revision,
             file_pool=None):
         self.changes.append((path, 'file', 'add'))
 
     def open_file(self, path, parent_baton, base_revision, file_pool=None):
         self.changes.append((path, 'file', 'change'))
 
 
 def authorization_callback_allow_all(root, path, pool):
     return True
 
 
 class TxnNodeProcessor(object):
     """
     Utility to process the change of one node within a transaction root.
 
     It encapsulates the knowledge of how to add, update or remove
     a node for a given transaction root. The purpose is to support the method
     `SvnRemote.commit`.
     """
 
     def __init__(self, node, txn_root):
         assert isinstance(node['path'], str)
 
         self.node = node
         self.txn_root = txn_root
 
     def update(self):
         self._ensure_parent_dirs()
         self._add_file_if_node_does_not_exist()
         self._update_file_content()
         self._update_file_properties()
 
     def remove(self):
         svn.fs.delete(self.txn_root, self.node['path'])
         # TODO: Clean up directory if empty
 
     def _ensure_parent_dirs(self):
         curdir = vcspath.dirname(self.node['path'])
         dirs_to_create = []
         while not self._svn_path_exists(curdir):
             dirs_to_create.append(curdir)
             curdir = vcspath.dirname(curdir)
 
         for curdir in reversed(dirs_to_create):
             log.debug('Creating missing directory "%s"', curdir)
             svn.fs.make_dir(self.txn_root, curdir)
 
     def _svn_path_exists(self, path):
         path_status = svn.fs.check_path(self.txn_root, path)
         return path_status != svn.core.svn_node_none
 
     def _add_file_if_node_does_not_exist(self):
         kind = svn.fs.check_path(self.txn_root, self.node['path'])
         if kind == svn.core.svn_node_none:
             svn.fs.make_file(self.txn_root, self.node['path'])
 
     def _update_file_content(self):
         assert isinstance(self.node['content'], str)
         handler, baton = svn.fs.apply_textdelta(
             self.txn_root, self.node['path'], None, None)
         svn.delta.svn_txdelta_send_string(self.node['content'], handler, baton)
 
     def _update_file_properties(self):
         properties = self.node.get('properties', {})
         for key, value in properties.iteritems():
             svn.fs.change_node_prop(
                 self.txn_root, self.node['path'], key, value)
 
 
 def apr_time_t(timestamp):
     """
     Convert a Python timestamp into APR timestamp type apr_time_t
     """
     return timestamp * 1E6
 
 
 def svn_opt_revision_value_t(num):
     """
     Put `num` into a `svn_opt_revision_value_t` structure.
     """
     value = svn.core.svn_opt_revision_value_t()
     value.number = num
     revision = svn.core.svn_opt_revision_t()
     revision.kind = svn.core.svn_opt_revision_number
     revision.value = value
     return revision