Naive GELF ouput implementation

lib/outputs/output_gelf.js

@@ -0,0 +1,70 @@
+var base_output = require('../lib/base_output'),
+    util = require('util'),
+    dgram = require('dgram'),
+    logger = require('log4node'),
+    zlib = require('zlib'),
+    error_buffer = require('../lib/error_buffer');
+
+function OutputGelf() {
+  base_output.BaseOutput.call(this);
+  this.config = {
+    name: 'Udp',
+    host_field: 'host',
+    port_field: 'port',
+    optional_params: ['error_buffer_delay', 'version', 'message', 'facility', 'level'],
+    default_values: {
+      'error_buffer_delay': 2000,
+      'version': '1.0',
+      'message': '#{@message}',
+      'facility': 'Node-logstash GELF',
+      'level': '6',
+    }
+  }
+}
+
+util.inherits(OutputGelf, base_output.BaseOutput);
+
+OutputGelf.prototype.afterLoadConfig = function(callback) {
+  logger.info('Start GELF output to', this.host + ':' + this.port);
+
+  this.socket = dgram.createSocket('udp4');
+
+  this.error_buffer = error_buffer.create('output GELF to ' + this.host + ':' + this.port, this.error_buffer_delay, this);
+
+  callback();
+}
+
+OutputGelf.prototype.process = function(data) {
+  var m = {
+    version: this.version,
+    short_message: this.replaceByFields(data, this.message),
+    facility: this.replaceByFields(data, this.facility),
+    host: data['@source_host'],
+    level: this.replaceByFields(data, this.level),
+    timestamp: (new Date(data['@timestamp'])).getTime() / 1000 >> 0,
+  };
+  if (!m.short_message) {
+    return;
+  }
+  logger.debug('Sending GELF', m);
+  zlib.deflate(new Buffer(JSON.stringify(m)), function(err, message) {
+    if (err) {
+      return this.error_buffer.emit('error', new Error('Error while compressing data:' + err));
+    }
+    this.socket.send(message, 0, message.length, this.port, this.host, function(err, bytes) {
+      if (err || bytes != message.length) {
+        this.error_buffer.emit('error', new Error('Error while send data to ' + this.host + ':' + this.port + ':' + err));
+      }
+    }.bind(this));
+  }.bind(this));
+}
+
+OutputGelf.prototype.close = function(callback) {
+  logger.info('Closing GELF output to udp', this.host + ':' + this.port);
+  this.socket.close();
+  callback();
+}
+
+exports.create = function() {
+  return new OutputGelf();
+}