attach: crash if initial-delivery-count is not 0

[mbroadst]

Hey, running into another parsing error it seems. I was wondering if you could help me figure out what's going on with it from the rabbitmq side (if I can better understand why these errors are happening, I can hopefully start submitting more relevant issues 😄). The error is:

=INFO REPORT==== 26-Mar-2015::13:43:47 ===
accepting AMQP connection <0.2116.0> (192.168.1.100:52559 -> 192.168.1.104:5672)

=ERROR REPORT==== 26-Mar-2015::13:43:47 ===
** Generic server <0.2123.0> terminating
** Last message in was {'$gen_cast',
                           {frame,
                               {'v1_0.attach',
                                   {utf8,<<"/topic/inventory.cell.info_TX">>},
                                   {uint,0},
                                   false,
                                   {ubyte,2},
                                   {ubyte,0},
                                   {'v1_0.source',
                                       {utf8,<<"localhost">>},
                                       {uint,0},
                                       {symbol,<<"session-end">>},
                                       {uint,0},
                                       false,
                                       {map,[]},
                                       undefined,
                                       {map,[]},
                                       undefined,undefined,undefined},
                                   {'v1_0.target',
                                       {utf8,<<"/topic/inventory.cell.info">>},
                                       {uint,0},
                                       {symbol,<<"session-end">>},
                                       {uint,0},
                                       false,
                                       {map,[]},
                                       undefined},
                                   {map,[]},
                                   false,
                                   {uint,1},
                                   {ulong,0},
                                   undefined,undefined,
                                   {map,[]}},
                               <0.2116.0>}}
** When Server state == {state,<0.2126.0>,<0.2132.0>,4294967287,<0.2116.0>,
                            <0.2122.0>,
                            {[],[]},
                            {session,1,100,100,1,65535,65535,0,65535,65535,0,
                                0,
                                {0,nil},
                                {0,nil}}}
** Reason for termination == 
** {{case_clause,
        {ok,{'v1_0.target',
                {utf8,<<"/topic/inventory.cell.info">>},
                {uint,0},
                {symbol,<<"session-end">>},
                {uint,0},
                false,
                {map,[]},
                undefined},
            {incoming_link,
                {utf8,<<"/topic/inventory.cell.info_TX">>},
                <<"amq.topic">>,<<"inventory.cell.info">>,undefined,0,
                undefined,undefined,32768,[],
                {set,0,16,16,8,80,48,
                    {[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]},
                    {{[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]}}}}}},
    [{rabbit_amqp1_0_incoming_link,attach,3,
         [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_incoming_link.erl"},
          {line,47}]},
     {rabbit_amqp1_0_session_process,with_disposable_channel,2,
         [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_session_process.erl"},
          {line,377}]},
     {rabbit_amqp1_0_session_process,handle_control,2,
         [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_session_process.erl"},
          {line,183}]},
     {rabbit_amqp1_0_session_process,handle_cast,2,
         [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_session_process.erl"},
          {line,134}]},
     {gen_server2,handle_msg,2,[{file,"src/gen_server2.erl"},{line,1034}]},
     {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,239}]}]}

=ERROR REPORT==== 26-Mar-2015::13:43:50 ===
closing AMQP connection <0.2116.0> (192.168.1.100:52559 -> 192.168.1.104:5672):
{handshake_error,running,<0.2123.0>,
    {{symbol,<<"amqp:internal-error">>},
     "Session error: ~p~n~p~n",
     [{case_clause,
          {ok,{'v1_0.target',
                  {utf8,<<"/topic/inventory.cell.info">>},
                  {uint,0},
                  {symbol,<<"session-end">>},
                  {uint,0},
                  false,
                  {map,[]},
                  undefined},
              {incoming_link,
                  {utf8,<<"/topic/inventory.cell.info_TX">>},
                  <<"amq.topic">>,<<"inventory.cell.info">>,undefined,0,
                  undefined,undefined,32768,[],
                  {set,0,16,16,8,80,48,
                      {[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]},
                      {{[],[],[],[],[],[],[],[],[],[],[],[],[],[],[],[]}}}}}},
      [{rabbit_amqp1_0_incoming_link,attach,3,
           [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_incoming_link.erl"},
            {line,47}]},
       {rabbit_amqp1_0_session_process,with_disposable_channel,2,
           [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_session_process.erl"},
            {line,377}]},
       {rabbit_amqp1_0_session_process,handle_control,2,
           [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_session_process.erl"},
            {line,183}]},
       {rabbit_amqp1_0_session_process,handle_cast,2,
           [{file,"rabbitmq-amqp1.0/src/rabbit_amqp1_0_session_process.erl"},
            {line,134}]},
       {gen_server2,handle_msg,2,[{file,"src/gen_server2.erl"},{line,1034}]},
       {proc_lib,init_p_do_apply,3,[{file,"proc_lib.erl"},{line,239}]}]]}}

I think this might be a problem with an invalid match on initial_delivery_count? But to be frank I'm a bit lost, and trying to play catchup

[simonmacmullen]

Yeah, we seem to be assuming it will be 0. That should be fixed, but in the mean time it might help you get further to set it to 0...

[mbroadst]

Okay I've been trying to parse through this a little bit more, now it seems to me that your attach frame matcher is perhaps incorrect? If I look at the spec, the performative definition is as follows:

<type name="attach" class="composite" source="list" provides="frame">
    <descriptor name="amqp:attach:list" code="0x00000000:0x00000012"/>
    <field name="name" type="string" mandatory="true"/>
    <field name="handle" type="handle" mandatory="true"/>
    <field name="role" type="role" mandatory="true"/>
    <field name="snd-settle-mode" type="sender-settle-mode" default="mixed"/>
    <field name="rcv-settle-mode" type="receiver-settle-mode" default="first"/>
    <field name="source" type="*" requires="source"/>
    <field name="target" type="*" requires="target"/>
    <field name="unsettled" type="map"/>
    <field name="incomplete-unsettled" type="boolean" default="false"/>
    <field name="initial-delivery-count" type="sequence-no"/>
    <field name="max-message-size" type="ulong"/>
    <field name="offered-capabilities" type="symbol" multiple="true"/>
    <field name="desired-capabilities" type="symbol" multiple="true"/>
    <field name="properties" type="fields"/>
</type>

and yet your definition for attach is as follows:

attach(#'v1_0.attach'{name = Name,
                      handle = Handle,
                      source = Source,
                      snd_settle_mode = SndSettleMode,
                      rcv_settle_mode = RcvSettleMode,
                      target = Target,
                      initial_delivery_count = {uint, InitTransfer}},

am I missing something?

[mbroadst]

we're actually sending initial delivery count as {uint,1} above

[mbroadst]

for extra help here, the js representation of the performative we are sending is:

{
    "descriptor": {
        "buffer": {
            "type": "Buffer",
            "data": [0, 0, 0, 0, 0, 0, 0, 18]
        },
        "offset": 0
    },
    "value": {
        "name": "/topic/inventory.cell.info_TX",
        "handle": {
            "typeName": "uint",
            "value": 0
        },
        "role": false,
        "senderSettleMode": {
            "typeName": "ubyte",
            "value": 2
        },
        "receiverSettleMode": {
            "typeName": "ubyte",
            "value": 0
        },
        "source": {
            "descriptor": {
                "buffer": {
                    "type": "Buffer",
                    "data": [0, 0, 0, 0, 0, 0, 0, 40]
                },
                "offset": 0
            },
            "address": "localhost",
            "durable": 0,
            "expiryPolicy": "session-end",
            "timeout": 0,
            "dynamic": false
        },
        "target": {
            "descriptor": {
                "buffer": {
                    "type": "Buffer",
                    "data": [0, 0, 0, 0, 0, 0, 0, 41]
                },
                "offset": 0
            },
            "address": "/topic/inventory.cell.info",
            "durable": 0,
            "expiryPolicy": {
                "contents": "session-end"
            },
            "timeout": 0,
            "dynamic": false
        },
        "unsettled": {},
        "incompleteUnsettled": false,
        "initialDeliveryCount": {
            "typeName": "uint",
            "value": 1
        },
        "maxMessageSize": {
            "typeName": "ulong",
            "value": 0
        },
        "offeredCapabilities": null,
        "desiredCapabilities": null,
        "properties": {},
        "encodeOrdering": ["name", "handle", "role", "senderSettleMode", "receiverSettleMode", "source", "target", "unsettled", "incompleteUnsettled", "initialDeliveryCount", "maxMessageSize", "offeredCapabilities", "desiredCapabilities", "properties"]
    }
}

and the raw hex is:

000000a002000001005312c0930ea11d2f746f7069632f696e76656e746f72792e63656c6c2e696e666f5f5458434250025000005328c0260ba1096c6f63616c686f737443a30b73657373696f6e2d656e644342c1010040c10100404040005329c03107a11a2f746f7069632f696e76656e746f72792e63656c6c2e696e666f43a30b73657373696f6e2d656e644342c1010040c10100425201444040c10100

[mbroadst]

@simonmacmullen the error seems to be in lines 52-82 of rabbit_amqp1_0_incoming_link, but that's about as far as I've gotten.. I find erlang's "backtraces" somewhat difficult to parse at this point , and would be very interested to learn how you did it when you do 😄

[mbroadst]

@simonmacmullen are those arguments meant to line up directly with the performative description?

[mbroadst]

@simonmacmullen lol, okay well after like an hour and a half of sifting through those 30 lines it turns out yes indeed, we are sending 1 as the initial message count and the bug is in fact that you guys assume 0.. I suppose we can chalk this up to a nice erlang learning experience!

[simonmacmullen]

Thanks!