@tsjing/nsqjs/lib/writer.js

NodeJS client for NSQ

// Generated by CoffeeScript 1.10.0
var ConnectionConfig, Debug, EventEmitter, Writer, WriterNSQDConnection, _,
  extend = function(child, parent) { for (var key in parent) { if (hasProp.call(parent, key)) child[key] = parent[key]; } function ctor() { this.constructor = child; } ctor.prototype = parent.prototype; child.prototype = new ctor(); child.__super__ = parent.prototype; return child; },
  hasProp = {}.hasOwnProperty;

Debug = require('debug');

EventEmitter = require('events').EventEmitter;

_ = require('underscore');

ConnectionConfig = require('./config').ConnectionConfig;

WriterNSQDConnection = require('./nsqdconnection').WriterNSQDConnection;


/*
Publish messages to nsqds.

Usage:

w = new Writer '127.0.0.1', 4150
w.connect()

w.on Writer.READY, ->
   * Send a single message
  w.publish 'sample_topic', 'one'
   * Send multiple messages
  w.publish 'sample_topic', ['two', 'three']
w.on Writer.CLOSED, ->
  console.log 'Writer closed'
 */

Writer = (function(superClass) {
  extend(Writer, superClass);

  Writer.READY = 'ready';

  Writer.CLOSED = 'closed';

  Writer.ERROR = 'error';

  function Writer(nsqdHost, nsqdPort, options) {
    this.nsqdHost = nsqdHost;
    this.nsqdPort = nsqdPort;
    Writer.__super__.constructor.apply(this, arguments);
    this.setMaxListeners(10000);
    this.debug = Debug("nsqjs:writer:" + this.nsqdHost + "/" + this.nsqdPort);
    this.config = new ConnectionConfig(options);
    this.config.validate();
    this.ready = false;
    this.debug('Configuration');
    this.debug(this.config);
  }

  Writer.prototype.connect = function() {
    this.conn = new WriterNSQDConnection(this.nsqdHost, this.nsqdPort, this.config);
    this.debug('connect');
    this.conn.connect();
    this.conn.on(WriterNSQDConnection.READY, (function(_this) {
      return function() {
        _this.debug('ready');
        _this.ready = true;
        return _this.emit(Writer.READY);
      };
    })(this));
    this.conn.on(WriterNSQDConnection.CLOSED, (function(_this) {
      return function() {
        _this.debug('closed');
        _this.ready = false;
        return _this.emit(Writer.CLOSED);
      };
    })(this));
    this.conn.on(WriterNSQDConnection.ERROR, (function(_this) {
      return function(err) {
        _this.debug('error', err);
        _this.ready = false;
        return _this.emit(Writer.ERROR, err);
      };
    })(this));
    return this.conn.on(WriterNSQDConnection.CONNECTION_ERROR, (function(_this) {
      return function(err) {
        _this.debug('error', err);
        _this.ready = false;
        return _this.emit(Writer.ERROR, err);
      };
    })(this));
  };


  /*
  Publish a message or a list of messages to the connected nsqd. The contents
  of the messages should either be strings or buffers with the payload encoded.
  
  Arguments:
    topic: A valid nsqd topic.
    msgs: A string, a buffer, a JSON serializable object, or
      a list of string / buffers / JSON serializable objects.
   */

  Writer.prototype.publish = function(topic, msgs, callback) {
    var connState, err, failed, msg, ready, ref, ref1, remove;
    connState = (ref = this.conn) != null ? (ref1 = ref.statemachine) != null ? ref1.current_state_name : void 0 : void 0;
    if (!this.conn || (connState === 'CLOSED' || connState === 'ERROR')) {
      err = new Error('No active Writer connection to send messages');
    }
    if (!msgs || _.isEmpty(msgs)) {
      err = new Error('Attempting to publish an empty message');
    }
    if (err) {
      if (callback) {
        return callback(err);
      }
      throw err;
    }
    if (!this.ready) {
      ready = (function(_this) {
        return function() {
          remove();
          return _this.publish(topic, msgs, callback);
        };
      })(this);
      failed = function(err) {
        err || (err = new Error('Connection closed!'));
        remove();
        return callback(err);
      };
      remove = (function(_this) {
        return function() {
          _this.removeListener(Writer.READY, ready);
          _this.removeListener(Writer.ERROR, failed);
          return _this.removeListener(Writer.CLOSED, failed);
        };
      })(this);
      this.on(Writer.READY, ready);
      this.on(Writer.ERROR, failed);
      this.on(Writer.CLOSED, failed);
      return;
    }
    if (!_.isArray(msgs)) {
      msgs = [msgs];
    }
    msgs = (function() {
      var i, len, results;
      results = [];
      for (i = 0, len = msgs.length; i < len; i++) {
        msg = msgs[i];
        if (_.isString(msg) || Buffer.isBuffer(msg)) {
          results.push(msg);
        } else {
          results.push(JSON.stringify(msg));
        }
      }
      return results;
    })();
    return this.conn.produceMessages(topic, msgs, callback);
  };

  Writer.prototype.close = function() {
    return this.conn.destroy();
  };

  return Writer;

})(EventEmitter);

module.exports = Writer;