fq

node-fq

fq message queue client written in Node.js.

Installation

npm install fq

Examples

Publish a Message

var FQ = require('fq');
var client = new FQ();
client.connect();
client.on('ready',function(){
    client.publish({
        route: 'test.prefix.foo',
        sender: 'bar',
        exchange: 'baz',
        payload: 'bang'
    }, function(err, res){
        console.log('done');
    })
});

Consume

var FQ = require('fq');

var client = new FQ();
client.connect();
client.on('ready', function(){
    client.bind('maryland','prefix:"test.prefix." sample(1)',0,function(err, res){
        client.consume();
    });
});
client.on('error', function(e){
    console.log('We have an error',e);
});
client.on('message', function(msg){
    console.log('Message:', msg);
    process.exit();
});    

FqClient

Configuring the Client

new Client(connOpts)

connOpts contains all of the parameters used in connecting to fq.

Note: There is no actual user authentication done by fq currently, but it requires the related parameters.

• host: 'localhost': (string) Host where fq is running.
• port: 8765: (number) Port fq is listening on.
• user: 'node-fq': (string) User to connect to fq as.
• pass: 'pass': (string) Password for user.
• queue: uuid(): (string) Which queue to connect to.
• queueType: 'mem': (string) The type of queue.
• heartbeat: 0: (number) What millisecond interval to send and look for a heartbeat. Use 0 for no heartbeat.

FqClient API

client.connect()

Connects to fq. This establishes two TCP connections, one for commands and one for data. It performs authorization and associates the two connections. Sets up heartbeat if client is configured to do so. The client will emit ready when complete.

client.setHeartbeat(hb)

• hb: (number) Millisecond interval to send heartbeat

Changes the heartbeat settings and alerts fq of the change.

client.bind(exchange, program, flags, callback)

• exchange: (string) Exchange to bind to
• program: (string) Route information.
• flags: (int)
  • : 0 (0x000000010)
  • peer: 1 (0x00000001)
  • perm: 272 (0x00000110)
  • trans: 256 (0x00000100)
• callback(err,binding): (function) Called after fq responds to the bind request.

Binds the client connection pair to a specific exchange and routing program. Required before consuming, but not necessary for publishing.

client.unbind(callback)

• callback(err,success): (function) Called after the fq responds to the unbind request

Unbinds the client connection pair.

client.publish(options, callback)

• options: (object)
  • msgId: uuid(): (string or buffer) Message ID
  • exchange: (string or buffer) Exchange to publish message to
  • route: (string or buffer) Routing information for message
  • payload: (string or buffer) Message payload
• callback(err,success): (function) Called after the message has been handled

Publishes a new message to the specified exchange with the specified routing information.

client.consume()

Turns on message consumption. It will emit message events as messages are read.

client.status(callback)

• callback(err, status): Function Called after fq responds with status info

Returns an object containing information about the current client session. These stats do not contain any aggregate information for fq as a whole. Example output:

{
  no_exchange: 0,
  no_route: 0,
  routed: 0,
  dropped: 0,
  msgs_in: 0,
  msgs_out: 0
}

FqClient Events

ready

Emitted when connection and authorization is fully complete. Client is ready to be used.

error

• err: Error

Emitted when a general error is encountered (i.e. not for an explicitly sent command or message).

message

• msg: FqMessage The message received

Emitted when a new message has been read

FqMessage

FqMessages store values as buffers and hops ips as arrays.

Example

{
  msgId: <Buffer 01 00 00 00 5a e8 5f 00 00 00 48 8b c6 48 8b 40>,
  numHops: 1,
  hops: [ [ 127, 0, 0, 1 ] ],
  routeLen: 15,
  route: <Buffer 74 65 73 74 2e 70 72 65 66 69 78 2e 66 6f 6f>,
  senderLen: 7,
  sender: <Buffer 6e 6f 64 65 2d 66 71>,
  exchangeLen: 8,
  exchange: <Buffer 6d 61 72 79 6c 61 6e 64>,
  payloadLen: 6,
  payload: <Buffer 66 6f 6f 62 61 72>,
  _complete: true,
}

FqMessage API

Only use the setters for setting values, as they will keep the *Len properties in sync with the values. The setters accept utf8 String or Buffer. There are also several getters for convenience that return utf8 String.

message.setMsgId(val)

Note: msgId is a 16 byte Buffer. Providing a Buffer or String longer will result in truncation.

message.setRoute(val)

message.getRoute()

message.setSender(val)

message.getSender()

message.setExchange(val)

message.getExchange()

message.getHops()

Returns an array of utf8 String

message.setPayload(val)

License

Copyright (c) 2013 OmniTI Computer Consulting, Inc. All rights reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.