[tor-commits] [ooni-probe/master] Implement retry logic inside of the oonibclient.

[art at torproject.org]

commit 1c3a5067ae9a26fc5c537e956e8c0847ad85fe4a
Author: Arturo Filastò <art at fuffa.org>
Date:   Thu Sep 12 15:00:31 2013 +0200

    Implement retry logic inside of the oonibclient.
---
 ooni/oonibclient.py |   37 ++++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/ooni/oonibclient.py b/ooni/oonibclient.py
index 24dc374..455aea8 100644
--- a/ooni/oonibclient.py
+++ b/ooni/oonibclient.py
@@ -42,26 +42,41 @@ class Collector(object):
         return False
 
 class OONIBClient(object):
+    retries = 3
+
     def __init__(self, address):
         self.address = address
         self.agent = Agent(reactor, sockshost="127.0.0.1", 
                            socksport=config.tor.socks_port)
 
     def _request(self, method, urn, genReceiver, bodyProducer=None):
-        finished = defer.Deferred()
+        attempts = 0
 
-        uri = self.address + urn
-        headers = {}
-        d = self.agent.request(method, uri, bodyProducer=bodyProducer)
+        finished = defer.Deferred()
 
-        @d.addCallback
-        def callback(response):
-            content_length = int(response.headers.getRawHeaders('content-length')[0])
-            response.deliverBody(genReceiver(finished, content_length))
+        def perform_request():
+            uri = self.address + urn
+            headers = {}
+            d = self.agent.request(method, uri, bodyProducer=bodyProducer)
 
-        @d.addErrback
-        def eb(err):
-            finished.errback(err)
+            @d.addCallback
+            def callback(response):
+                content_length = int(response.headers.getRawHeaders('content-length')[0])
+                response.deliverBody(genReceiver(finished, content_length))
+
+            def errback(err, attempts):
+                # We we will recursively keep trying to perform a request until
+                # we have reached the retry count.
+                if attempts < self.retries:
+                    log.err("Lookup failed. Retrying.")
+                    attempts += 1
+                    perform_request()
+                else:
+                    log.err("Failed. Giving up.")
+                    finished.errback(err)
+            d.addErrback(errback, attempts)
+
+        perform_request()
 
         return finished