+ # Lookup hash in cache
+ locations = self.db.lookupHash(hash.expected())
+ self.getCachedFile(hash, req, path, d, locations)
+
+ def getCachedFile(self, hash, req, path, d, locations):
+ if not locations:
+ log.msg('Failed to return file from cache: %s' % path)
+ self.lookupHash(hash, path, d)
+ return
+
+ # Get the first possible location from the list
+ file = locations.pop(0)['path']
+ log.msg('Returning cached file: %s' % file.path)
+
+ # Get it's response
+ resp = static.File(file.path).renderHTTP(req)
+ if isinstance(resp, defer.Deferred):
+ resp.addBoth(self._getCachedFile, hash, req, path, d, locations)
+ else:
+ self._getCachedFile(resp, hash, req, path, d, locations)
+
+ def _getCachedFile(self, resp, hash, req, path, d, locations):
+ if isinstance(resp, failure.Failure):
+ log.msg('Got error trying to get cached file')
+ log.err()
+ # Try the next possible location
+ self.getCachedFile(hash, req, path, d, locations)
+ return
+
+ log.msg('Cached response: %r' % resp)
+
+ if resp.code >= 200 and resp.code < 400:
+ d.callback(resp)
+ else:
+ # Try the next possible location
+ self.getCachedFile(hash, req, path, d, locations)
+
+ def lookupHash(self, hash, path, d):
+ log.msg('Looking up hash in DHT for file: %s' % path)
+ key = hash.normexpected(bits = config.getint(config.get('DEFAULT', 'DHT'), 'HASH_LENGTH'))
+ lookupDefer = self.dht.getValue(key)
+ lookupDefer.addCallback(self.lookupHash_done, hash, path, d)
+