QPID-3208: Exchanges make best effort to route messages if there is an error.

Previously if multiple queues were bound to the same routing key,
then a failure to deliver to one of the queues (e.g. policy limit
error) could prevent delivery on some of the other queues.

With this commit the exchange delivers to every queue that did not
have an error before raising an error.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1092765 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 56 insertions, 3 deletions

diff --git a/qpid/cpp/src/qpid/broker/Exchange.cpp b/qpid/cpp/src/qpid/broker/Exchange.cpp
index 2c7589e4b6..7cf3ec162f 100644
--- a/qpid/cpp/src/qpid/broker/Exchange.cpp
+++ b/qpid/cpp/src/qpid/broker/Exchange.cpp
@@ -29,6 +29,7 @@
 #include "qpid/framing/MessageProperties.h"
 #include "qpid/framing/reply_exceptions.h"
 #include "qpid/broker/DeliverableMessage.h"
+#include "stdexcept"
 
 using namespace qpid::broker;
 using namespace qpid::framing;
@@ -70,6 +71,44 @@ Exchange::PreRoute::~PreRoute(){
     }
 }
 
+namespace {
+/** Store information about an exception to be thrown later.
+ * If multiple exceptions are stored, save the first of the "most severe"
+ * exceptions, SESSION is les sever than CONNECTION etc.
+ */
+class  ExInfo {
+  public:
+    enum Type { NONE, SESSION, CONNECTION, OTHER };
+
+    ExInfo(string ex) : type(NONE), code(0), exchange(ex) {}
+
+    void store(Type type_, const char* what_, int code_, const boost::shared_ptr<Queue>& queue) {
+        QPID_LOG(error, "Exchange " << exchange << " cannot deliver to  queue "
+                 <<  queue->getName() << ": " << what_);
+        if (type < type_) {     // Replace less severe error
+            type = type_;
+            what = what_;
+            code = code_;
+        }
+    }
+
+    void raise() {
+        switch (type) {
+          case  NONE: break;
+          case SESSION: throw qpid::SessionException(qpid::framing::execution::ErrorCode(code), what);
+          case CONNECTION: throw qpid::ConnectionException(qpid::framing::connection::CloseCode(code), what);
+          case OTHER: throw std::runtime_error(what);
+        }
+    }
+
+  private:
+    Type type;
+    string what;
+    int code;
+    string exchange;
+};
+}
+
 void Exchange::doRoute(Deliverable& msg, ConstBindingList b)
 {
     int count = 0;
@@ -80,11 +119,25 @@ void Exchange::doRoute(Deliverable& msg, ConstBindingList b)
             msg.getMessage().blockContentRelease();
         }
 
+
+        ExInfo error(getName());           // Save errors to throw at the end.
         for(std::vector<Binding::shared_ptr>::const_iterator i = b->begin(); i != b->end(); i++, count++) {
-            msg.deliverTo((*i)->queue);
-            if ((*i)->mgmtBinding != 0)
-                (*i)->mgmtBinding->inc_msgMatched();
+            try {
+                msg.deliverTo((*i)->queue);
+                if ((*i)->mgmtBinding != 0)
+                    (*i)->mgmtBinding->inc_msgMatched();
+            }
+            catch (const SessionException& e) {
+                error.store(ExInfo::SESSION, e.what(), int(e.code), (*i)->queue);
+            }
+            catch (const ConnectionException& e) {
+                error.store(ExInfo::CONNECTION, e.what(), int(e.code), (*i)->queue);
+            }
+            catch (const std::exception& e) {
+                error.store(ExInfo::OTHER, e.what(), 0, (*i)->queue);
+            }
         }
+        error.raise();
     }
 
     if (mgmtExchange != 0)