def mirror_from_sources_list(self, uri, default_uri):
"""
try to figure what the mirror is from current sources.list
do this by looing for matching DEFAULT_COMPONENT, current dist
in sources.list and then doing a http HEAD/ftp size request
to see if the uri is available on this server
"""
self._debug("mirror_from_sources_list: %s" % self.current_dist_name)
sources = SourcesList(withMatcher=False)
seen = set()
for e in sources.list:
if e.disabled or e.invalid or not e.type == "deb":
continue
# check if we probed this mirror already
if e.uri in seen:
continue
# we are using the main mirror already, so we are fine
if (e.uri.startswith(default_uri) and
e.dist == self.current_dist_name and
self.DEFAULT_COMPONENT in e.comps):
return uri
elif (e.dist == self.current_dist_name and
"main" in e.comps):
mirror_uri = e.uri+uri[len(default_uri):]
if url_downloadable(mirror_uri, self._debug):
return mirror_uri
seen.add(e.uri)
self._debug("no mirror found")
return ""
def _expandUri(self, uri):
"""
expand the uri so that it uses a mirror if the url starts
with a well know string (like archive.ubuntu.com)
"""
# try to guess the mirror from the sources.list
if uri.startswith(self.DEFAULT_MIRROR):
self._debug("trying to find suitable mirror")
new_uri = self.mirror_from_sources_list(uri, self.DEFAULT_MIRROR)
if new_uri:
return new_uri
# if that fails, use old method
uri_template = Template(uri)
m = country_mirror()
new_uri = uri_template.safe_substitute(countrymirror=m)
# be paranoid and check if the given uri is really downloadable
try:
if not url_downloadable(new_uri, self._debug):
raise Exception("failed to download %s" % new_uri)
except Exception,e:
self._debug("url '%s' could not be downloaded" % e)
# else fallback to main server
new_uri = uri_template.safe_substitute(countrymirror='')
