git: use rev-list for fetching last commit data inc ase of single commit. It's faster that using git log

rhodecode/lib/vcs/backends/git/commit.py

@@ -1,530 +1,534 b''
 # -*- coding: utf-8 -*-
 
 # Copyright (C) 2014-2019 RhodeCode GmbH
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU Affero General Public License, version 3
 # (only), as published by the Free Software Foundation.
 #
 # 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 Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 # This program is dual-licensed. If you wish to learn more about the
 # RhodeCode Enterprise Edition, including its added features, Support services,
 # and proprietary license terms, please see https://rhodecode.com/licenses/
 
 """
 GIT commit module
 """
 
 import re
 import stat
 from itertools import chain
 from StringIO import StringIO
 
 from zope.cachedescriptors.property import Lazy as LazyProperty
 
 from rhodecode.lib.datelib import utcdate_fromtimestamp
 from rhodecode.lib.utils import safe_unicode, safe_str
 from rhodecode.lib.utils2 import safe_int
 from rhodecode.lib.vcs.conf import settings
 from rhodecode.lib.vcs.backends import base
 from rhodecode.lib.vcs.exceptions import CommitError, NodeDoesNotExistError
 from rhodecode.lib.vcs.nodes import (
     FileNode, DirNode, NodeKind, RootNode, SubModuleNode,
     ChangedFileNodesGenerator, AddedFileNodesGenerator,
     RemovedFileNodesGenerator, LargeFileNode)
 from rhodecode.lib.vcs.compat import configparser
 
 
 class GitCommit(base.BaseCommit):
     """
     Represents state of the repository at single commit id.
     """
     _author_property = 'author'
     _committer_property = 'committer'
     _date_property = 'commit_time'
     _date_tz_property = 'commit_timezone'
     _message_property = 'message'
     _parents_property = 'parents'
 
     _filter_pre_load = [
         # done through a more complex tree walk on parents
         "affected_files",
         # based on repository cached property
         "branch",
         # done through subprocess not remote call
         "children",
         # done through a more complex tree walk on parents
         "status",
         # mercurial specific property not supported here
         "_file_paths",
         # mercurial specific property not supported here
         'obsolete',
         # mercurial specific property not supported here
         'phase',
         # mercurial specific property not supported here
         'hidden'
     ]
 
     def __init__(self, repository, raw_id, idx, pre_load=None):
         self.repository = repository
         self._remote = repository._remote
         # TODO: johbo: Tweak of raw_id should not be necessary
         self.raw_id = safe_str(raw_id)
         self.idx = idx
 
         self._set_bulk_properties(pre_load)
 
         # caches
         self._stat_modes = {}  # stat info for paths
         self._paths = {}  # path processed with parse_tree
         self.nodes = {}
         self._submodules = None
 
     def _set_bulk_properties(self, pre_load):
         if not pre_load:
             return
         pre_load = [entry for entry in pre_load
                     if entry not in self._filter_pre_load]
         if not pre_load:
             return
 
         result = self._remote.bulk_request(self.raw_id, pre_load)
         for attr, value in result.items():
             if attr in ["author", "message"]:
                 if value:
                     value = safe_unicode(value)
             elif attr == "date":
                 value = utcdate_fromtimestamp(*value)
             elif attr == "parents":
                 value = self._make_commits(value)
             self.__dict__[attr] = value
 
     @LazyProperty
     def _commit(self):
         return self._remote[self.raw_id]
 
     @LazyProperty
     def _tree_id(self):
         return self._remote[self._commit['tree']]['id']
 
     @LazyProperty
     def id(self):
         return self.raw_id
 
     @LazyProperty
     def short_id(self):
         return self.raw_id[:12]
 
     @LazyProperty
     def message(self):
         return safe_unicode(
             self._remote.commit_attribute(self.id, self._message_property))
 
     @LazyProperty
     def committer(self):
         return safe_unicode(
             self._remote.commit_attribute(self.id, self._committer_property))
 
     @LazyProperty
     def author(self):
         return safe_unicode(
             self._remote.commit_attribute(self.id, self._author_property))
 
     @LazyProperty
     def date(self):
         unix_ts, tz = self._remote.get_object_attrs(
             self.raw_id, self._date_property, self._date_tz_property)
         return utcdate_fromtimestamp(unix_ts, tz)
 
     @LazyProperty
     def status(self):
         """
         Returns modified, added, removed, deleted files for current commit
         """
         return self.changed, self.added, self.removed
 
     @LazyProperty
     def tags(self):
         tags = [safe_unicode(name) for name,
                 commit_id in self.repository.tags.iteritems()
                 if commit_id == self.raw_id]
         return tags
 
     @LazyProperty
     def branch(self):
         for name, commit_id in self.repository.branches.iteritems():
             if commit_id == self.raw_id:
                 return safe_unicode(name)
         return None
 
     def _get_id_for_path(self, path):
         path = safe_str(path)
         if path in self._paths:
             return self._paths[path]
 
         tree_id = self._tree_id
 
         path = path.strip('/')
         if path == '':
             data = [tree_id, "tree"]
             self._paths[''] = data
             return data
 
         parts = path.split('/')
         dirs, name = parts[:-1], parts[-1]
         cur_dir = ''
 
         # initially extract things from root dir
         tree_items = self._remote.tree_items(tree_id)
         self._process_tree_items(tree_items, cur_dir)
 
         for dir in dirs:
             if cur_dir:
                 cur_dir = '/'.join((cur_dir, dir))
             else:
                 cur_dir = dir
             dir_id = None
             for item, stat_, id_, type_ in tree_items:
                 if item == dir:
                     dir_id = id_
                     break
             if dir_id:
                 if type_ != "tree":
                     raise CommitError('%s is not a directory' % cur_dir)
                 # update tree
                 tree_items = self._remote.tree_items(dir_id)
             else:
                 raise CommitError('%s have not been found' % cur_dir)
 
             # cache all items from the given traversed tree
             self._process_tree_items(tree_items, cur_dir)
 
         if path not in self._paths:
             raise self.no_node_at_path(path)
 
         return self._paths[path]
 
     def _process_tree_items(self, items, cur_dir):
         for item, stat_, id_, type_ in items:
             if cur_dir:
                 name = '/'.join((cur_dir, item))
             else:
                 name = item
             self._paths[name] = [id_, type_]
             self._stat_modes[name] = stat_
 
     def _get_kind(self, path):
         path_id, type_ = self._get_id_for_path(path)
         if type_ == 'blob':
             return NodeKind.FILE
         elif type_ == 'tree':
             return NodeKind.DIR
         elif type == 'link':
             return NodeKind.SUBMODULE
         return None
 
     def _get_filectx(self, path):
         path = self._fix_path(path)
         if self._get_kind(path) != NodeKind.FILE:
             raise CommitError(
                 "File does not exist for commit %s at  '%s'" %
                 (self.raw_id, path))
         return path
 
     def _get_file_nodes(self):
         return chain(*(t[2] for t in self.walk()))
 
     @LazyProperty
     def parents(self):
         """
         Returns list of parent commits.
         """
         parent_ids = self._remote.commit_attribute(
             self.id, self._parents_property)
         return self._make_commits(parent_ids)
 
     @LazyProperty
     def children(self):
         """
         Returns list of child commits.
         """
         rev_filter = settings.GIT_REV_FILTER
         output, __ = self.repository.run_git_command(
             ['rev-list', '--children'] + rev_filter)
 
         child_ids = []
         pat = re.compile(r'^%s' % self.raw_id)
         for l in output.splitlines():
             if pat.match(l):
                 found_ids = l.split(' ')[1:]
                 child_ids.extend(found_ids)
         return self._make_commits(child_ids)
 
     def _make_commits(self, commit_ids, pre_load=None):
         return [
             self.repository.get_commit(commit_id=commit_id, pre_load=pre_load)
             for commit_id in commit_ids]
 
     def get_file_mode(self, path):
         """
         Returns stat mode of the file at the given `path`.
         """
         path = safe_str(path)
         # ensure path is traversed
         self._get_id_for_path(path)
         return self._stat_modes[path]
 
     def is_link(self, path):
         return stat.S_ISLNK(self.get_file_mode(path))
 
     def get_file_content(self, path):
         """
         Returns content of the file at given `path`.
         """
         id_, _ = self._get_id_for_path(path)
         return self._remote.blob_as_pretty_string(id_)
 
     def get_file_size(self, path):
         """
         Returns size of the file at given `path`.
         """
         id_, _ = self._get_id_for_path(path)
         return self._remote.blob_raw_length(id_)
 
     def get_path_history(self, path, limit=None, pre_load=None):
         """
         Returns history of file as reversed list of `GitCommit` objects for
         which file at given `path` has been modified.
 
         TODO: This function now uses an underlying 'git' command which works
         quickly but ideally we should replace with an algorithm.
         """
         self._get_filectx(path)
         f_path = safe_str(path)
 
+        # optimize for n==1, rev-list is much faster for that use-case
+        if limit == 1:
+            cmd = ['rev-list', '-1', self.raw_id, '--', f_path]
+        else:
         cmd = ['log']
         if limit:
             cmd.extend(['-n', str(safe_int(limit, 0))])
         cmd.extend(['--pretty=format: %H', '-s', self.raw_id, '--', f_path])
 
         output, __ = self.repository.run_git_command(cmd)
         commit_ids = re.findall(r'[0-9a-fA-F]{40}', output)
 
         return [
             self.repository.get_commit(commit_id=commit_id, pre_load=pre_load)
             for commit_id in commit_ids]
 
     def get_file_annotate(self, path, pre_load=None):
         """
         Returns a generator of four element tuples with
             lineno, commit_id, commit lazy loader and line
 
         TODO: This function now uses os underlying 'git' command which is
         generally not good. Should be replaced with algorithm iterating
         commits.
         """
         cmd = ['blame', '-l', '--root', '-r', self.raw_id, '--', path]
         # -l     ==> outputs long shas (and we need all 40 characters)
         # --root ==> doesn't put '^' character for bounderies
         # -r commit_id ==> blames for the given commit
         output, __ = self.repository.run_git_command(cmd)
 
         for i, blame_line in enumerate(output.split('\n')[:-1]):
             line_no = i + 1
             commit_id, line = re.split(r' ', blame_line, 1)
             yield (
                 line_no, commit_id,
                 lambda: self.repository.get_commit(commit_id=commit_id,
                                                    pre_load=pre_load),
                 line)
 
     def get_nodes(self, path):
         if self._get_kind(path) != NodeKind.DIR:
             raise CommitError(
                 "Directory does not exist for commit %s at "
                 " '%s'" % (self.raw_id, path))
         path = self._fix_path(path)
         id_, _ = self._get_id_for_path(path)
         tree_id = self._remote[id_]['id']
         dirnodes = []
         filenodes = []
         alias = self.repository.alias
         for name, stat_, id_, type_ in self._remote.tree_items(tree_id):
             if type_ == 'link':
                 url = self._get_submodule_url('/'.join((path, name)))
                 dirnodes.append(SubModuleNode(
                     name, url=url, commit=id_, alias=alias))
                 continue
 
             if path != '':
                 obj_path = '/'.join((path, name))
             else:
                 obj_path = name
             if obj_path not in self._stat_modes:
                 self._stat_modes[obj_path] = stat_
 
             if type_ == 'tree':
                 dirnodes.append(DirNode(obj_path, commit=self))
             elif type_ == 'blob':
                 filenodes.append(FileNode(obj_path, commit=self, mode=stat_))
             else:
                 raise CommitError(
                     "Requested object should be Tree or Blob, is %s", type_)
 
         nodes = dirnodes + filenodes
         for node in nodes:
             if node.path not in self.nodes:
                 self.nodes[node.path] = node
         nodes.sort()
         return nodes
 
     def get_node(self, path, pre_load=None):
         if isinstance(path, unicode):
             path = path.encode('utf-8')
         path = self._fix_path(path)
         if path not in self.nodes:
             try:
                 id_, type_ = self._get_id_for_path(path)
             except CommitError:
                 raise NodeDoesNotExistError(
                     "Cannot find one of parents' directories for a given "
                     "path: %s" % path)
 
             if type_ == 'link':
                 url = self._get_submodule_url(path)
                 node = SubModuleNode(path, url=url, commit=id_,
                                      alias=self.repository.alias)
             elif type_ == 'tree':
                 if path == '':
                     node = RootNode(commit=self)
                 else:
                     node = DirNode(path, commit=self)
             elif type_ == 'blob':
                 node = FileNode(path, commit=self, pre_load=pre_load)
             else:
                 raise self.no_node_at_path(path)
 
             # cache node
             self.nodes[path] = node
         return self.nodes[path]
 
     def get_largefile_node(self, path):
         id_, _ = self._get_id_for_path(path)
         pointer_spec = self._remote.is_large_file(id_)
 
         if pointer_spec:
             # content of that file regular FileNode is the hash of largefile
             file_id = pointer_spec.get('oid_hash')
             if self._remote.in_largefiles_store(file_id):
                 lf_path = self._remote.store_path(file_id)
                 return LargeFileNode(lf_path, commit=self, org_path=path)
 
     @LazyProperty
     def affected_files(self):
         """
         Gets a fast accessible file changes for given commit
         """
         added, modified, deleted = self._changes_cache
         return list(added.union(modified).union(deleted))
 
     @LazyProperty
     def _changes_cache(self):
         added = set()
         modified = set()
         deleted = set()
         _r = self._remote
 
         parents = self.parents
         if not self.parents:
             parents = [base.EmptyCommit()]
         for parent in parents:
             if isinstance(parent, base.EmptyCommit):
                 oid = None
             else:
                 oid = parent.raw_id
             changes = _r.tree_changes(oid, self.raw_id)
             for (oldpath, newpath), (_, _), (_, _) in changes:
                 if newpath and oldpath:
                     modified.add(newpath)
                 elif newpath and not oldpath:
                     added.add(newpath)
                 elif not newpath and oldpath:
                     deleted.add(oldpath)
         return added, modified, deleted
 
     def _get_paths_for_status(self, status):
         """
         Returns sorted list of paths for given ``status``.
 
         :param status: one of: *added*, *modified* or *deleted*
         """
         added, modified, deleted = self._changes_cache
         return sorted({
             'added': list(added),
             'modified': list(modified),
             'deleted': list(deleted)}[status]
         )
 
     @LazyProperty
     def added(self):
         """
         Returns list of added ``FileNode`` objects.
         """
         if not self.parents:
             return list(self._get_file_nodes())
         return AddedFileNodesGenerator(
             [n for n in self._get_paths_for_status('added')], self)
 
     @LazyProperty
     def changed(self):
         """
         Returns list of modified ``FileNode`` objects.
         """
         if not self.parents:
             return []
         return ChangedFileNodesGenerator(
             [n for n in self._get_paths_for_status('modified')], self)
 
     @LazyProperty
     def removed(self):
         """
         Returns list of removed ``FileNode`` objects.
         """
         if not self.parents:
             return []
         return RemovedFileNodesGenerator(
             [n for n in self._get_paths_for_status('deleted')], self)
 
     def _get_submodule_url(self, submodule_path):
         git_modules_path = '.gitmodules'
 
         if self._submodules is None:
             self._submodules = {}
 
             try:
                 submodules_node = self.get_node(git_modules_path)
             except NodeDoesNotExistError:
                 return None
 
             content = submodules_node.content
 
             # ConfigParser fails if there are whitespaces
             content = '\n'.join(l.strip() for l in content.split('\n'))
 
             parser = configparser.ConfigParser()
             parser.readfp(StringIO(content))
 
             for section in parser.sections():
                 path = parser.get(section, 'path')
                 url = parser.get(section, 'url')
                 if path and url:
                     self._submodules[path.strip('/')] = url
 
         return self._submodules.get(submodule_path.strip('/'))