Changeset 469:30576260957d

Timestamp:

08/25/08 13:45:02 (5 months ago)

Author:

Brian Warner <warner@allmydata.com>

branch:

default

Message:

replace ConnectionDone? and ConnectionClosed? with DeadReferenceError?, so application code only has to check for a single exception type. Closes #89.

Files:

• ChangeLog (modified) (1 diff)
• foolscap/broker.py (modified) (1 diff)
• foolscap/negotiate.py (modified) (4 diffs)
• foolscap/test/test_call.py (modified) (4 diffs)
• foolscap/test/test_gifts.py (modified) (6 diffs)

ChangeLog

@@ +1 @@
+2008-08-25  Brian Warner  <warner@lothar.com>
+
+        * foolscap/broker.py (Broker.abandonAllRequests): map both
+        ConnectionLost and ConnectionDone into DeadReferenceError, so that
+        application code only needs to check for one exception type.
+        * foolscap/negotiate.py (Negotiation.evaluateNegotiationVersion1):
+        when an existing connection is dropped in favor of a new one, drop
+        it with DeadReferenceError instead of ConnectionDone. The mapping
+        in Broker.abandonAllRequests doesn't seem to quite catch
+        everything in unit tests.
+        (Negotiation.acceptDecisionVersion1): same, when we're the slave
+        * foolscap/test/test_call.py (TestCall.test_connection_lost_is_deadref):
+        test it
+        (TestCall.test_connection_done_is_deadref): same
+        (TestCall.testChoiceOf): switch to use ShouldFailMixin
+        * foolscap/test/test_gifts.py (Gifts): remove
+        ignoreConnectionDone, just look for DeadReferenceError
+
-2008-08-21  Brian Warner  <warner@lothar.com>
-

foolscap/broker.py

@@ -483 +483 @@
-
-    def abandonAllRequests(self, why):
+        # map all connection-lost errors to DeadReferenceError, so
+        # application code only needs to check for one exception type
+        if why.check(error.ConnectionLost, error.ConnectionDone):
+            why = failure.Failure(DeadReferenceError("Connection was lost"))
-        for req in self.waitingForAnswers.values():
-            eventually(req.fail, why)

foolscap/negotiate.py

@@ -4 +4 @@
-from twisted.python.failure import Failure
-from twisted.internet import protocol, reactor
-from twisted.internet.error import ConnectionDone
-
-from foolscap import broker, referenceable, vocab
@@ -10 +9 @@
-from foolscap.tokens import SIZE_LIMIT, ERROR, \
-     BananaError, NegotiationError, RemoteNegotiationError
+from foolscap.ipb import DeadReferenceError
-from foolscap.banana import int2b128
-from foolscap.logging import log
@@ -785 +785 @@
-                    self.log("accepting new offer, dropping existing connection",
-                             parent=lp)
-ConnectionDone
-
+DeadReferenceError
+    
-                    why = Failure(err)
-                    existing.shutdown(why)
@@ -1079 +1079 @@
-            self.log("master told us to use a new connection, "
-                     "so we must drop the existing one", level=UNUSUAL)
-ConnectionDone
+DeadReferenceError
-            why = Failure(err)
-            self.tub.brokers[self.theirTubRef].shutdown(why)

foolscap/test/test_call.py

@@ -11 +11 @@
-from twisted.python import log
-from twisted.trial import unittest
-
+, CONNECTION_DONE
-from twisted.python.failure import Failure
-
-from foolscap.tokens import Violation
-from foolscap.eventual import flushEventualQueue
-
+, ShouldFailMixin
-from foolscap.test.common import RIMyTarget, Target, TargetWithoutInterfaces, \
-     BrokenTarget
+from foolscap import DeadReferenceError
-
-class Unsendable:
@@ -24 +25 @@
-
-
-
+ShouldFailMixin, 
-    def setUp(self):
-        TargetMixin.setUp(self)
@@ -201 +202 @@
-        d.addCallback(lambda res: rr.callRemote("choice1", "a"*2000))
-        d.addCallback(lambda res: self.failUnlessEqual(res, None))
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
+
+
+
+
+
-
-    def testMegaSchema(self):
@@ -410 +398 @@
-        return d
-
+    def test_connection_lost_is_deadref(self):
+        rr, target = self.setupTarget(HelperTarget())
+        d1 = rr.callRemote("hang")
+        def get_d(): return d1
+        rr.tracker.broker.transport.loseConnection(Failure(CONNECTION_LOST))
+        d = self.shouldFail(DeadReferenceError, "lost_is_deadref.1",
+                            "Connection was lost",
+                            get_d)
+        # and once the connection is down, we should get a DeadReferenceError
+        # for new messages
+        d.addCallback(lambda res:
+                      self.shouldFail(DeadReferenceError, "lost_is_deadref.2",
+                                      "Calling Stale Broker",
+                                      rr.callRemote, "hang"))
+        return d
+
+    def test_connection_done_is_deadref(self):
+        rr, target = self.setupTarget(HelperTarget())
+        d = rr.callRemote("hang")
+        rr.tracker.broker.transport.loseConnection(Failure(CONNECTION_DONE))
+        d.addCallbacks(lambda res: self.fail("should have failed"),
+                       lambda why: why.trap(DeadReferenceError) and None)
+        return d
+
-    def disconnected(self, *args, **kwargs):
-        self.lost = 1

foolscap/test/test_gifts.py

@@ -3 +3 @@
-from twisted.trial import unittest
-from twisted.internet import defer, protocol, reactor
-
-
+
-from twisted.python import failure
-from foolscap import RemoteInterface, Referenceable
@@ -12 +11 @@
-from foolscap.eventual import flushEventualQueue
-from foolscap.tokens import BananaError, NegotiationError
-
-def ignoreConnectionDone(f):
-    f.trap(ConnectionDone, ConnectionLost)
-    return None
-
-class RIConstrainedHelper(RemoteInterface):
@@ -161 +156 @@
-            if self.debug: print "Alice introduces Carol to Bob"
-            # send the gift. This might not get acked by the time the test is
-
-
-
-
-
+
+
-            return d2 # this fires with the gift that bob got
-        d.addCallback(_introduce)
@@ -174 +166 @@
-            d2 = self.carol.waitfor()
-            # handle ConnectionDone as described before
-
-
+
-            return d2
-        d.addCallback(_bobGotCarol)
@@ -212 +203 @@
-            # ConnectionDone error that might result. When we get
-            # callRemoteOnly(), use that instead.
-
-
-
-
+
+
+
-            return d2 # this fires with the gift that bob got
-        d.addCallback(_introduce)
@@ -230 +220 @@
-
-            # handle ConnectionDone as described before
-
-
-
-
+
+
-            return defer.DeferredList([d2,d3])
-        d.addCallback(_bobGotCarol)