extensions: preparatory refactoring

Small refactoring:

- use 'try..except' rather than 'if-then', which removes the need for a
  separate 'path' variable and is more 'pythonic'.
- promote log from 'debug' to 'info' and execute it immediately after
  loading before anything else.
- clarify comments related to INDEX_EXTENSIONS

kallithea/lib/utils.py

@@ -1,596 +1,597 b''
 # -*- coding: utf-8 -*-
 # 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, see <http://www.gnu.org/licenses/>.
 """
 kallithea.lib.utils
 ~~~~~~~~~~~~~~~~~~~
 
 Utilities library for Kallithea
 
 This file was forked by the Kallithea project in July 2014.
 Original author and date, and relevant copyright and licensing information is below:
 :created_on: Apr 18, 2010
 :author: marcink
 :copyright: (c) 2013 RhodeCode GmbH, and others.
 :license: GPLv3, see LICENSE.md for more details.
 """
 
 import datetime
 import logging
 import os
 import re
 import sys
 import traceback
 import urllib.error
 from distutils.version import StrictVersion
 
 import mercurial.config
 import mercurial.error
 import mercurial.ui
 
 import kallithea.config.conf
 from kallithea.lib.exceptions import InvalidCloneUriException
 from kallithea.lib.utils2 import ascii_bytes, aslist, get_current_authuser, safe_bytes, safe_str
 from kallithea.lib.vcs.backends.git.repository import GitRepository
 from kallithea.lib.vcs.backends.hg.repository import MercurialRepository
 from kallithea.lib.vcs.conf import settings
 from kallithea.lib.vcs.exceptions import RepositoryError, VCSError
 from kallithea.lib.vcs.utils.fakemod import create_module
 from kallithea.lib.vcs.utils.helpers import get_scm
 from kallithea.model import db, meta
 from kallithea.model.db import RepoGroup, Repository, Setting, Ui, User, UserGroup, UserLog
 
 
 log = logging.getLogger(__name__)
 
 REMOVED_REPO_PAT = re.compile(r'rm__\d{8}_\d{6}_\d{6}_.*')
 
 
 #==============================================================================
 # PERM DECORATOR HELPERS FOR EXTRACTING NAMES FOR PERM CHECKS
 #==============================================================================
 def get_repo_slug(request):
     _repo = request.environ['pylons.routes_dict'].get('repo_name')
     if _repo:
         _repo = _repo.rstrip('/')
     return _repo
 
 
 def get_repo_group_slug(request):
     _group = request.environ['pylons.routes_dict'].get('group_name')
     if _group:
         _group = _group.rstrip('/')
     return _group
 
 
 def get_user_group_slug(request):
     _group = request.environ['pylons.routes_dict'].get('id')
     _group = UserGroup.get(_group)
     if _group:
         return _group.users_group_name
     return None
 
 
 def _get_permanent_id(s):
     """Helper for decoding stable URLs with repo ID. For a string like '_123'
     return 123.
     """
     by_id_match = re.match(r'^_(\d+)$', s)
     if by_id_match is None:
         return None
     return int(by_id_match.group(1))
 
 
 def fix_repo_id_name(path):
     """
     Rewrite repo_name for _<ID> permanent URLs.
 
     Given a path, if the first path element is like _<ID>, return the path with
     this part expanded to the corresponding full repo name, else return the
     provided path.
     """
     first, rest = path, ''
     if '/' in path:
         first, rest_ = path.split('/', 1)
         rest = '/' + rest_
     repo_id = _get_permanent_id(first)
     if repo_id is not None:
         repo = Repository.get(repo_id)
         if repo is not None:
             return repo.repo_name + rest
     return path
 
 
 def action_logger(user, action, repo, ipaddr='', commit=False):
     """
     Action logger for various actions made by users
 
     :param user: user that made this action, can be a unique username string or
         object containing user_id attribute
     :param action: action to log, should be on of predefined unique actions for
         easy translations
     :param repo: string name of repository or object containing repo_id,
         that action was made on
     :param ipaddr: optional IP address from what the action was made
 
     """
 
     # if we don't get explicit IP address try to get one from registered user
     # in tmpl context var
     if not ipaddr:
         ipaddr = getattr(get_current_authuser(), 'ip_addr', '')
 
     if getattr(user, 'user_id', None):
         user_obj = User.get(user.user_id)
     elif isinstance(user, str):
         user_obj = User.get_by_username(user)
     else:
         raise Exception('You have to provide a user object or a username')
 
     if getattr(repo, 'repo_id', None):
         repo_obj = Repository.get(repo.repo_id)
         repo_name = repo_obj.repo_name
     elif isinstance(repo, str):
         repo_name = repo.lstrip('/')
         repo_obj = Repository.get_by_repo_name(repo_name)
     else:
         repo_obj = None
         repo_name = ''
 
     user_log = UserLog()
     user_log.user_id = user_obj.user_id
     user_log.username = user_obj.username
     user_log.action = action
 
     user_log.repository = repo_obj
     user_log.repository_name = repo_name
 
     user_log.action_date = datetime.datetime.now()
     user_log.user_ip = ipaddr
     meta.Session().add(user_log)
 
     log.info('Logging action:%s on %s by user:%s ip:%s',
              action, repo, user_obj, ipaddr)
     if commit:
         meta.Session().commit()
 
 
 def get_filesystem_repos(path):
     """
     Scans given path for repos and return (name,(type,path)) tuple
 
     :param path: path to scan for repositories
     :param recursive: recursive search and return names with subdirs in front
     """
 
     # remove ending slash for better results
     path = path.rstrip(os.sep)
     log.debug('now scanning in %s', path)
 
     def isdir(*n):
         return os.path.isdir(os.path.join(*n))
 
     for root, dirs, _files in os.walk(path):
         recurse_dirs = []
         for subdir in dirs:
             # skip removed repos
             if REMOVED_REPO_PAT.match(subdir):
                 continue
 
             # skip .<something> dirs TODO: rly? then we should prevent creating them ...
             if subdir.startswith('.'):
                 continue
 
             cur_path = os.path.join(root, subdir)
             if isdir(cur_path, '.git'):
                 log.warning('ignoring non-bare Git repo: %s', cur_path)
                 continue
 
             if (isdir(cur_path, '.hg') or
                 isdir(cur_path, '.svn') or
                 isdir(cur_path, 'objects') and (isdir(cur_path, 'refs') or
                                                 os.path.isfile(os.path.join(cur_path, 'packed-refs')))):
 
                 if not os.access(cur_path, os.R_OK) or not os.access(cur_path, os.X_OK):
                     log.warning('ignoring repo path without access: %s', cur_path)
                     continue
 
                 if not os.access(cur_path, os.W_OK):
                     log.warning('repo path without write access: %s', cur_path)
 
                 try:
                     scm_info = get_scm(cur_path)
                     assert cur_path.startswith(path)
                     repo_path = cur_path[len(path) + 1:]
                     yield repo_path, scm_info
                     continue # no recursion
                 except VCSError:
                     # We should perhaps ignore such broken repos, but especially
                     # the bare git detection is unreliable so we dive into it
                     pass
 
             recurse_dirs.append(subdir)
 
         dirs[:] = recurse_dirs
 
 
 def is_valid_repo_uri(repo_type, url, ui):
     """Check if the url seems like a valid remote repo location
     Raise InvalidCloneUriException if any problems"""
     if repo_type == 'hg':
         if url.startswith('http') or url.startswith('ssh'):
             # initially check if it's at least the proper URL
             # or does it pass basic auth
             try:
                 MercurialRepository._check_url(url, ui)
             except urllib.error.URLError as e:
                 raise InvalidCloneUriException('URI %s URLError: %s' % (url, e))
             except mercurial.error.RepoError as e:
                 raise InvalidCloneUriException('Mercurial %s: %s' % (type(e).__name__, safe_str(bytes(e))))
         elif url.startswith('svn+http'):
             try:
                 from hgsubversion.svnrepo import svnremoterepo
             except ImportError:
                 raise InvalidCloneUriException('URI type %s not supported - hgsubversion is not available' % (url,))
             svnremoterepo(ui, url).svn.uuid
         elif url.startswith('git+http'):
             raise InvalidCloneUriException('URI type %s not implemented' % (url,))
         else:
             raise InvalidCloneUriException('URI %s not allowed' % (url,))
 
     elif repo_type == 'git':
         if url.startswith('http') or url.startswith('git'):
             # initially check if it's at least the proper URL
             # or does it pass basic auth
             try:
                 GitRepository._check_url(url)
             except urllib.error.URLError as e:
                 raise InvalidCloneUriException('URI %s URLError: %s' % (url, e))
         elif url.startswith('svn+http'):
             raise InvalidCloneUriException('URI type %s not implemented' % (url,))
         elif url.startswith('hg+http'):
             raise InvalidCloneUriException('URI type %s not implemented' % (url,))
         else:
             raise InvalidCloneUriException('URI %s not allowed' % (url))
 
 
 def is_valid_repo(repo_name, base_path, scm=None):
     """
     Returns True if given path is a valid repository False otherwise.
     If scm param is given also compare if given scm is the same as expected
     from scm parameter
 
     :param repo_name:
     :param base_path:
     :param scm:
 
     :return True: if given path is a valid repository
     """
     # TODO: paranoid security checks?
     full_path = os.path.join(base_path, repo_name)
 
     try:
         scm_ = get_scm(full_path)
         if scm:
             return scm_[0] == scm
         return True
     except VCSError:
         return False
 
 
 def is_valid_repo_group(repo_group_name, base_path, skip_path_check=False):
     """
     Returns True if given path is a repository group False otherwise
 
     :param repo_name:
     :param base_path:
     """
     full_path = os.path.join(base_path, repo_group_name)
 
     # check if it's not a repo
     if is_valid_repo(repo_group_name, base_path):
         return False
 
     try:
         # we need to check bare git repos at higher level
         # since we might match branches/hooks/info/objects or possible
         # other things inside bare git repo
         get_scm(os.path.dirname(full_path))
         return False
     except VCSError:
         pass
 
     # check if it's a valid path
     if skip_path_check or os.path.isdir(full_path):
         return True
 
     return False
 
 
 def make_ui(repo_path=None):
     """
     Create an Mercurial 'ui' object based on database Ui settings, possibly
     augmenting with content from a hgrc file.
     """
     baseui = mercurial.ui.ui()
 
     # clean the baseui object
     baseui._ocfg = mercurial.config.config()
     baseui._ucfg = mercurial.config.config()
     baseui._tcfg = mercurial.config.config()
 
     sa = meta.Session()
     for ui_ in sa.query(Ui).order_by(Ui.ui_section, Ui.ui_key):
         if ui_.ui_active:
             log.debug('config from db: [%s] %s=%r', ui_.ui_section,
                       ui_.ui_key, ui_.ui_value)
             baseui.setconfig(ascii_bytes(ui_.ui_section), ascii_bytes(ui_.ui_key),
                              b'' if ui_.ui_value is None else safe_bytes(ui_.ui_value))
 
     # force set push_ssl requirement to False, Kallithea handles that
     baseui.setconfig(b'web', b'push_ssl', False)
     baseui.setconfig(b'web', b'allow_push', b'*')
     # prevent interactive questions for ssh password / passphrase
     ssh = baseui.config(b'ui', b'ssh', default=b'ssh')
     baseui.setconfig(b'ui', b'ssh', b'%s -oBatchMode=yes -oIdentitiesOnly=yes' % ssh)
     # push / pull hooks
     baseui.setconfig(b'hooks', b'changegroup.kallithea_log_push_action', b'python:kallithea.lib.hooks.log_push_action')
     baseui.setconfig(b'hooks', b'outgoing.kallithea_log_pull_action', b'python:kallithea.lib.hooks.log_pull_action')
 
     if repo_path is not None:
         # Note: MercurialRepository / mercurial.localrepo.instance will do this too, so it will always be possible to override db settings or what is hardcoded above
         baseui.readconfig(repo_path)
 
     assert baseui.plain()  # set by hgcompat.monkey_do (invoked from import of vcs.backends.hg) to minimize potential impact of loading config files
     return baseui
 
 
 def set_app_settings(config):
     """
     Updates app config with new settings from database
 
     :param config:
     """
     hgsettings = Setting.get_app_settings()
     for k, v in hgsettings.items():
         config[k] = v
     config['base_path'] = Ui.get_repos_location()
 
 
 def set_vcs_config(config):
     """
     Patch VCS config with some Kallithea specific stuff
 
     :param config: kallithea.CONFIG
     """
     settings.BACKENDS = {
         'hg': 'kallithea.lib.vcs.backends.hg.MercurialRepository',
         'git': 'kallithea.lib.vcs.backends.git.GitRepository',
     }
 
     settings.GIT_EXECUTABLE_PATH = config.get('git_path', 'git')
     settings.GIT_REV_FILTER = config.get('git_rev_filter', '--all').strip()
     settings.DEFAULT_ENCODINGS = aslist(config.get('default_encoding',
                                                         'utf-8'), sep=',')
 
 
 def set_indexer_config(config):
     """
     Update Whoosh index mapping
 
     :param config: kallithea.CONFIG
     """
     log.debug('adding extra into INDEX_EXTENSIONS')
     kallithea.config.conf.INDEX_EXTENSIONS.extend(re.split(r'\s+', config.get('index.extensions', '')))
 
     log.debug('adding extra into INDEX_FILENAMES')
     kallithea.config.conf.INDEX_FILENAMES.extend(re.split(r'\s+', config.get('index.filenames', '')))
 
 
 def map_groups(path):
     """
     Given a full path to a repository, create all nested groups that this
     repo is inside. This function creates parent-child relationships between
     groups and creates default perms for all new groups.
 
     :param paths: full path to repository
     """
     from kallithea.model.repo_group import RepoGroupModel
     sa = meta.Session()
     groups = path.split(db.URL_SEP)
     parent = None
     group = None
 
     # last element is repo in nested groups structure
     groups = groups[:-1]
     rgm = RepoGroupModel()
     owner = User.get_first_admin()
     for lvl, group_name in enumerate(groups):
         group_name = '/'.join(groups[:lvl] + [group_name])
         group = RepoGroup.get_by_group_name(group_name)
         desc = '%s group' % group_name
 
         # skip folders that are now removed repos
         if REMOVED_REPO_PAT.match(group_name):
             break
 
         if group is None:
             log.debug('creating group level: %s group_name: %s',
                       lvl, group_name)
             group = RepoGroup(group_name, parent)
             group.group_description = desc
             group.owner = owner
             sa.add(group)
             rgm._create_default_perms(group)
             sa.flush()
 
         parent = group
     return group
 
 
 def repo2db_mapper(initial_repo_dict, remove_obsolete=False,
                    install_git_hooks=False, user=None, overwrite_git_hooks=False):
     """
     maps all repos given in initial_repo_dict, non existing repositories
     are created, if remove_obsolete is True it also check for db entries
     that are not in initial_repo_dict and removes them.
 
     :param initial_repo_dict: mapping with repositories found by scanning methods
     :param remove_obsolete: check for obsolete entries in database
     :param install_git_hooks: if this is True, also check and install git hook
         for a repo if missing
     :param overwrite_git_hooks: if this is True, overwrite any existing git hooks
         that may be encountered (even if user-deployed)
     """
     from kallithea.model.repo import RepoModel
     from kallithea.model.scm import ScmModel
     sa = meta.Session()
     repo_model = RepoModel()
     if user is None:
         user = User.get_first_admin()
     added = []
 
     # creation defaults
     defs = Setting.get_default_repo_settings(strip_prefix=True)
     enable_statistics = defs.get('repo_enable_statistics')
     enable_downloads = defs.get('repo_enable_downloads')
     private = defs.get('repo_private')
 
     for name, repo in sorted(initial_repo_dict.items()):
         group = map_groups(name)
         db_repo = repo_model.get_by_repo_name(name)
         # found repo that is on filesystem not in Kallithea database
         if not db_repo:
             log.info('repository %s not found, creating now', name)
             added.append(name)
             desc = (repo.description
                     if repo.description != 'unknown'
                     else '%s repository' % name)
 
             new_repo = repo_model._create_repo(
                 repo_name=name,
                 repo_type=repo.alias,
                 description=desc,
                 repo_group=getattr(group, 'group_id', None),
                 owner=user,
                 enable_downloads=enable_downloads,
                 enable_statistics=enable_statistics,
                 private=private,
                 state=Repository.STATE_CREATED
             )
             sa.commit()
             # we added that repo just now, and make sure it has githook
             # installed, and updated server info
             if new_repo.repo_type == 'git':
                 git_repo = new_repo.scm_instance
                 ScmModel().install_git_hooks(git_repo)
                 # update repository server-info
                 log.debug('Running update server info')
                 git_repo._update_server_info()
             new_repo.update_changeset_cache()
         elif install_git_hooks:
             if db_repo.repo_type == 'git':
                 ScmModel().install_git_hooks(db_repo.scm_instance, force=overwrite_git_hooks)
 
     removed = []
     # remove from database those repositories that are not in the filesystem
     for repo in sa.query(Repository).all():
         if repo.repo_name not in initial_repo_dict:
             if remove_obsolete:
                 log.debug("Removing non-existing repository found in db `%s`",
                           repo.repo_name)
                 try:
                     RepoModel().delete(repo, forks='detach', fs_remove=False)
                     sa.commit()
                 except Exception:
                     #don't hold further removals on error
                     log.error(traceback.format_exc())
                     sa.rollback()
             removed.append(repo.repo_name)
     return added, removed
 
 
 def load_extensions(root_path):
-    path = os.path.join(root_path, 'rcextensions', '__init__.py')
-    if os.path.isfile(path):
-        ext = create_module('rc', path)
+    try:
+        ext = create_module('rc', os.path.join(root_path, 'rcextensions', '__init__.py'))
+    except FileNotFoundError:
+        return
+
+    log.info('Loaded rcextensions from %s', ext)
         kallithea.EXTENSIONS = ext
-        log.debug('Found rcextensions now loading %s...', ext)
 
         # Additional mappings that are not present in the pygments lexers
         kallithea.config.conf.LANGUAGES_EXTENSIONS_MAP.update(getattr(ext, 'EXTRA_MAPPINGS', {}))
 
-        # OVERRIDE OUR EXTENSIONS FROM RC-EXTENSIONS (if present)
-
+    # Override any INDEX_EXTENSIONS
         if getattr(ext, 'INDEX_EXTENSIONS', []):
             log.debug('settings custom INDEX_EXTENSIONS')
             kallithea.config.conf.INDEX_EXTENSIONS = getattr(ext, 'INDEX_EXTENSIONS', [])
 
-        # ADDITIONAL MAPPINGS
+    # Additional INDEX_EXTENSIONS
         log.debug('adding extra into INDEX_EXTENSIONS')
         kallithea.config.conf.INDEX_EXTENSIONS.extend(getattr(ext, 'EXTRA_INDEX_EXTENSIONS', []))
 
 
 #==============================================================================
 # MISC
 #==============================================================================
 
 git_req_ver = StrictVersion('1.7.4')
 
 def check_git_version():
     """
     Checks what version of git is installed on the system, and raise a system exit
     if it's too old for Kallithea to work properly.
     """
     if 'git' not in kallithea.BACKENDS:
         return None
 
     if not settings.GIT_EXECUTABLE_PATH:
         log.warning('No git executable configured - check "git_path" in the ini file.')
         return None
 
     try:
         stdout, stderr = GitRepository._run_git_command(['--version'])
     except RepositoryError as e:
         # message will already have been logged as error
         log.warning('No working git executable found - check "git_path" in the ini file.')
         return None
 
     if stderr:
         log.warning('Error/stderr from "%s --version":\n%s', settings.GIT_EXECUTABLE_PATH, safe_str(stderr))
 
     if not stdout:
         log.warning('No working git executable found - check "git_path" in the ini file.')
         return None
 
     output = safe_str(stdout).strip()
     m = re.search(r"\d+.\d+.\d+", output)
     if m:
         ver = StrictVersion(m.group(0))
         log.debug('Git executable: "%s", version %s (parsed from: "%s")',
                   settings.GIT_EXECUTABLE_PATH, ver, output)
         if ver < git_req_ver:
             log.error('Kallithea detected %s version %s, which is too old '
                       'for the system to function properly. '
                       'Please upgrade to version %s or later. '
                       'If you strictly need Mercurial repositories, you can '
                       'clear the "git_path" setting in the ini file.',
                       settings.GIT_EXECUTABLE_PATH, ver, git_req_ver)
             log.error("Terminating ...")
             sys.exit(1)
     else:
         ver = StrictVersion('0.0.0')
         log.warning('Error finding version number in "%s --version" stdout:\n%s',
                     settings.GIT_EXECUTABLE_PATH, output)
 
     return ver