# Copyright (C) 2012-2013,2015 Codethink Limited
#
# 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; version 2 of the License.
#
# 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 .
import logging
import re
class RepoAlias(object):
def __init__(self, alias, prefix, pullpat, pushpat):
self.alias = alias
self.prefix = prefix
self.pullpat = pullpat
self.pushpat = pushpat
def _pattern_to_regex(self, pattern):
if '%s' in pattern:
return r'(?P.+)'.join(map(re.escape, pattern.split('%s')))
else:
return re.escape(pattern) + r'(?P.+)'
def match_url(self, url):
'''Given a URL, return what its alias would be if it matches'''
for pat in (self.pullpat, self.pushpat):
m = re.match(self._pattern_to_regex(pat), url)
if m:
return '%s:%s' % (self.prefix, m.group('path'))
return None
class RepoAliasResolver(object):
def __init__(self, aliases):
self.aliases = {}
alias_pattern = (r'^(?P[a-z][a-z0-9-]+)'
r'=(?P[^#]+)#(?P[^#]+)$')
for alias in aliases:
m = re.match(alias_pattern, alias)
if not m:
logging.warning('Alias %s is malformed' % alias)
continue
prefix = m.group('prefix')
self.aliases[prefix] = RepoAlias(alias, prefix, m.group('pullpat'),
m.group('pushpat'))
def pull_url(self, reponame):
'''Expand a possibly shortened repo name to a pull url.'''
return self._expand_reponame(reponame, 'pullpat')
def push_url(self, reponame):
'''Expand a possibly shortened repo name to a push url.'''
return self._expand_reponame(reponame, 'pushpat')
def aliases_from_url(self, url):
'''Find aliases the url could have expanded from.
Returns an ascii-betically sorted list.
'''
potential_matches = (repo_alias.match_url(url)
for repo_alias in self.aliases.itervalues())
known_aliases = (url_alias for url_alias in potential_matches
if url_alias is not None)
return sorted(known_aliases)
def _expand_reponame(self, reponame, patname):
prefix, suffix = self._split_reponame(reponame)
# There was no prefix.
if prefix is None:
result = reponame
elif prefix not in self.aliases:
# Unknown prefix. Which means it may be a real URL instead.
# Let the caller deal with it.
result = reponame
else:
pat = getattr(self.aliases[prefix], patname)
result = self._apply_url_pattern(pat, suffix)
logging.debug("Expansion of %s for %s yielded: %s" %
(reponame, patname, result))
return result
def _split_reponame(self, reponame):
'''Split reponame into prefix and suffix.
The prefix is returned as None if there was no prefix.
'''
pat = r'^(?P[a-z][a-z0-9-]+):(?P.*)$'
m = re.match(pat, reponame)
if m:
return m.group('prefix'), m.group('rest')
else:
return None, reponame
def _apply_url_pattern(self, pattern, shortname):
if '%s' in pattern:
return shortname.join(pattern.split('%s'))
else:
return pattern + shortname