[AMQ-6881] Error during transfer when sender doesn't include initial-delivery-count in attach

• Type: Bug
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: AMQP
• Assignee: Unassigned
• Reporter: Kale Blankenship
• Created: 04/Jan/18 02:06
• Updated: 11/Jan/18 02:44

Description

I'm not sure whether this will be considered a bug, but I figured I'd at least let you know.

I ran across this issue while testing my Go AMQP implementation against ActiveMQ. When attempting to send messages to ActiveMQ the connection would be terminated an error like `AmqpProtocolException: Could not decode AMQP frame: hex: ...`. I eventually tracked this down to my client not including initial-delivery-count in the attach. The spec is clear that the field "MUST NOT be null if role is sender," so it was an oversight on my part.

I was surprised that the failure occurred when the first transfer frame was sent rather than the malformed attach. Though my Java knowledge is very limited, the stack trace I was able to get (by removing some of the handling) implies that the delivery-count in ActiveMQ/Proton was not initialized during the attach and then caused a NullPointerException when the delivery-count was incremented while processing the transfer.

```
java.lang.NullPointerException
at org.apache.qpid.proton.engine.impl.TransportLink.incrementDeliveryCount(TransportLink.java:202)
at org.apache.qpid.proton.engine.impl.TransportSession.handleTransfer(TransportSession.java:326)
at org.apache.qpid.proton.engine.impl.TransportImpl.handleTransfer(TransportImpl.java:1266)
at org.apache.qpid.proton.engine.impl.TransportImpl.handleTransfer(TransportImpl.java:66)
at org.apache.qpid.proton.amqp.transport.Transfer.invoke(Transfer.java:160)
at org.apache.qpid.proton.engine.impl.TransportImpl.handleFrame(TransportImpl.java:1384)
at org.apache.qpid.proton.engine.impl.FrameParser.input(FrameParser.java:418)
at org.apache.qpid.proton.engine.impl.FrameParser.process(FrameParser.java:527)
at org.apache.qpid.proton.engine.impl.SaslImpl$SaslTransportWrapper.reallyProcessInput(SaslImpl.java:658)
at org.apache.qpid.proton.engine.impl.SaslImpl$SaslTransportWrapper.process(SaslImpl.java:607)
at org.apache.qpid.proton.engine.impl.HandshakeSniffingTransportWrapper.process(HandshakeSniffingTransportWrapper.java:101)
at org.apache.qpid.proton.engine.impl.TransportImpl.process(TransportImpl.java:1495)
at org.apache.qpid.proton.engine.impl.TransportImpl.processInput(TransportImpl.java:1453)
at org.apache.qpid.proton.engine.impl.TransportImpl.input(TransportImpl.java:298)
at org.apache.activemq.transport.amqp.protocol.AmqpConnection.onAMQPData(AmqpConnection.java:373)
at org.apache.activemq.transport.amqp.AmqpTransportFilter.onCommand(AmqpTransportFilter.java:109)
at org.apache.activemq.transport.TransportSupport.doConsume(TransportSupport.java:83)
at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:233)
at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:215)
at java.base/java.lang.Thread.run(Thread.java:844)
```