def delegateRendering(graphType, graphOptions):
start = time()
postData = graphType + '\n' + pickle.dumps(graphOptions)
servers = settings.RENDERING_HOSTS[:] #make a copy so we can shuffle it safely
shuffle(servers)
for server in servers:
start2 = time()
try:
# Get a connection
try:
pool = connectionPools[server]
except KeyError: #happens the first time
pool = connectionPools[server] = set()
try:
connection = pool.pop()
except KeyError: #No available connections, have to make a new one
connection = HTTPConnectionWithTimeout(server)
connection.timeout = settings.REMOTE_RENDER_CONNECT_TIMEOUT
# Send the request
try:
connection.request('POST', '/render/local/', postData)
except CannotSendRequest:
connection = HTTPConnectionWithTimeout(server) #retry once
connection.timeout = settings.REMOTE_RENDER_CONNECT_TIMEOUT
connection.request('POST', '/render/local/', postData)
# Read the response
response = connection.getresponse()
assert response.status == 200, "Bad response code %d from %s" % (
response.status, server)
contentType = response.getheader('Content-Type')
imageData = response.read()
assert contentType == 'image/png', "Bad content type: \"%s\" from %s" % (
contentType, server)
assert imageData, "Received empty response from %s" % server
# Wrap things up
log.rendering('Remotely rendered image on %s in %.6f seconds' %
(server, time() - start2))
log.rendering(
'Spent a total of %.6f seconds doing remote rendering work' %
(time() - start))
pool.add(connection)
return imageData
except:
log.exception(
"Exception while attempting remote rendering request on %s" %
server)
log.rendering(
'Exception while remotely rendering on %s wasted %.6f' %
(server, time() - start2))
continue
def renderMyGraphView(request, username, graphName):
profile = getProfileByUsername(username)
assert profile, "No such user '%s'" % username
try:
graph = profile.mygraph_set.get(name=graphName)
except ObjectDoesNotExist:
assert False, "User %s doesn't have a MyGraph named '%s'" % (username,
graphName)
(proto, host, path, query, frag) = urlsplit(graph.url)
if query: path += '?' + query
conn = HTTPConnectionWithTimeout(host)
conn.request('GET', path)
resp = conn.getresponse()
assert resp.status == 200, "Failed to retrieve image from URL %s" % graph.url
imageData = resp.read()
return buildResponse(imageData)
