+ # Force one month max age if no Cache-Control header is found
+ # Overriding header disappearance on LastFM web service...
+ # https://getsatisfaction.com/lastfm/topics/-web-api-http-cache-control-header
+ elif CacheController.CACHE_ANYWAY:
+ resp.headers['Cache-Control'] = 'max-age=2419200'
+ self.cache.set(cache_url, resp)
+
+ def update_cached_response(self, request, response):
+ """On a 304 we will get a new set of headers that we want to
+ update our cached value with, assuming we have one.
+
+ This should only ever be called when we've sent an ETag and
+ gotten a 304 as the response.
+ """
+ cache_url = self.cache_url(request.url)
+
+ resp = self.cache.get(cache_url)
+
+ if not resp:
+ # we didn't have a cached response
+ return response
+
+ # did so lets update our headers
+ resp.headers.update(response.headers)
+
+ # we want a 200 b/c we have content via the cache
+ request.status_code = 200
+
+ # update the request as it has the if-none-match header + any
+ # other headers that the server might have updated (ie Date,
+ # Cache-Control, Expires, etc.)
+ resp.request = request
+
+ # update our cache
+ self.cache.set(cache_url, resp)
+
+ # Let everyone know this was from the cache.
+ resp.from_cache = True
+
+ return resp
+
+
+class HttpClient:
+ def __init__(self, cache=None, stats=None):
+ """
+ Prepare http request
+ Use cached elements or proceed http request
+ """
+ self.stats = stats
+ self.controller = CacheController(cache)
+ self.sess = Session()
+
+ def __call__(self, ress, payload):
+ req = Request('GET', ress, params=payload,).prepare()
+ if self.stats:
+ self.stats.update(total=self.stats.get('total')+1)
+ cached_response = self.controller.cached_request(req)
+ if cached_response:
+ if self.stats:
+ self.stats.update(ccontrol=self.stats.get('ccontrol')+1)
+ return cached_response
+ try:
+ return self.fetch_ws(req)
+ except Timeout:
+ raise WSTimeout('Failed to reach server within {0}s'.format(
+ SOCKET_TIMEOUT))
+ except ConnectionError as err:
+ raise WSError(err)
+
+ @Throttle(WAIT_BETWEEN_REQUESTS)
+ def fetch_ws(self, prepreq):
+ """fetch from web service"""
+ settings = self.sess.merge_environment_settings(prepreq.url, {}, None, False, None)
+ resp = self.sess.send(prepreq, timeout=SOCKET_TIMEOUT, **settings)
+ if resp.status_code == 304:
+ self.stats.update(etag=self.stats.get('etag')+1)
+ resp = self.controller.update_cached_response(prepreq, resp)
+ elif resp.status_code != 200:
+ raise WSHTTPError('{0.status_code}: {0.reason}'.format(resp))
+ self.controller.cache_response(resp.request, resp)
+ return resp
+
+# VIM MODLINE
+# vim: ai ts=4 sw=4 sts=4 expandtab