adding logstash UDP appender

README.md

@@ -13,6 +13,7 @@ Out of the box it supports the following features:
 * GELF appender
 * hook.io appender
 * Loggly appender
+* Logstash UDP appender
 * multiprocess appender (useful when you've got worker processes)
 * a logger for connect/express servers
 * configurable log message layout/patterns

examples/logstashUDP.js

@@ -0,0 +1,39 @@
+var log4js = require('../lib/log4js');
+
+/*
+ Sample logstash config:
+   udp {
+    codec => json
+    port => 10001
+    queue_size => 2
+    workers => 2
+    type => myAppType
+  }
+*/
+
+log4js.configure({
+  "appenders": [
+    {
+      type: "console",
+      category: "myLogger"
+    },
+    {
+      "host": "127.0.0.1",
+      "port": 10001,
+      "type": "logstashUDP",
+      "logType": "myAppType", // Optional, defaults to 'category'
+      "fields": {             // Optional, will be added to the 'fields' object in logstash
+        "field1": "value1",
+        "field2": "value2"
+      },
+      "layout": {
+        "type": "pattern",
+        "pattern": "%m"
+      },
+      "category": "myLogger"
+    }
+  ]
+});
+
+var logger = log4js.getLogger("myLogger");
+logger.info("Test log message %s", "arg1", "arg2");

lib/appenders/logstashUDP.js

@@ -0,0 +1,50 @@
+"use strict";
+var layouts = require('../layouts')
+, dgram = require('dgram')
+, util = require('util');
+
+function logstashUDP (config, layout) {
+  var udp = dgram.createSocket('udp4');
+  var type = config.logType ? config.logType : config.category;
+  layout = layout || layouts.colouredLayout;
+  if(!config.fields) {
+    config.fields = {};
+  }
+  return function(loggingEvent) {
+    var logMessage = layout(loggingEvent);
+    var fields = {};
+    for(var i in config.fields) {
+      fields[i] = config.fields[i];
+    }
+    fields['level'] = loggingEvent.level.levelStr;
+    var logObject = {
+      '@timestamp': (new Date(loggingEvent.startTime)).toISOString(),
+      type: type,
+      message: logMessage,
+      fields: fields
+    };
+    sendLog(udp, config.host, config.port, logObject);
+  };
+}
+
+function sendLog(udp, host, port, logObject) {
+  var buffer = new Buffer(JSON.stringify(logObject));
+  udp.send(buffer, 0, buffer.length, port, host, function(err, bytes) {
+    if(err) {
+      console.error(
+        "log4js.logstashUDP - %s:%p Error: %s", host, port, util.inspect(err)
+      );
+    }
+  });
+}
+
+function configure(config) {
+  var layout;
+  if (config.layout) {
+    layout = layouts.layout(config.layout.type, config.layout);
+  }
+  return logstashUDP(config, layout);
+}
+
+exports.appender = logstashUDP;
+exports.configure = configure;

test/logstashUDP-test.js

@@ -0,0 +1,106 @@
+"use strict";
+var sys = require("sys");
+var vows = require('vows')
+, assert = require('assert')
+, log4js = require('../lib/log4js')
+, sandbox = require('sandboxed-module')
+;
+
+function setupLogging(category, options) {
+  var udpSent = {};
+  
+  var fakeDgram = {
+    createSocket: function (type) {
+      return {
+        send: function(buffer, offset, length, port, host, callback) {
+          udpSent.date = new Date();
+          udpSent.host = host;
+          udpSent.port = port;
+          udpSent.length = length;
+          udpSent.offset = 0;
+          udpSent.buffer = buffer;
+          callback(undefined, length);
+        }
+      };
+    }
+  };
+
+  var logstashModule = sandbox.require('../lib/appenders/logstashUDP', {
+    requires: {
+      'dgram': fakeDgram
+    }
+  });
+  log4js.clearAppenders();
+  log4js.addAppender(logstashModule.configure(options), category);
+  
+  return {
+    logger: log4js.getLogger(category),
+    results: udpSent
+  };
+}
+
+vows.describe('logstashUDP appender').addBatch({
+  'when logging with logstash via UDP': {
+    topic: function() {
+      var setup = setupLogging('logstashUDP', {
+        "host": "127.0.0.1",
+        "port": 10001,
+        "type": "logstashUDP",
+        "logType": "myAppType",
+        "category": "myLogger",
+        "fields": {
+          "field1": "value1",
+          "field2": "value2"
+        },
+        "layout": {
+          "type": "pattern",
+          "pattern": "%m"
+        }
+      });
+      setup.logger.log('trace', 'Log event #1');
+      return setup;
+    },
+    'an UDP packet should be sent': function (topic) {
+      assert.equal(topic.results.host, "127.0.0.1");
+      assert.equal(topic.results.port, 10001);
+      assert.equal(topic.results.offset, 0);
+      var json = JSON.parse(topic.results.buffer.toString());
+      assert.equal(json.type, 'myAppType');
+      var fields = {
+        field1: 'value1',
+        field2: 'value2',
+        level: 'TRACE'
+      };
+      assert.equal(JSON.stringify(json.fields), JSON.stringify(fields));
+      assert.equal(json.message, 'Log event #1');
+      // Assert timestamp, up to hours resolution.
+      var date = new Date(json['@timestamp']);
+      assert.equal(
+        date.toISOString().substring(0, 14),
+        topic.results.date.toISOString().substring(0, 14)
+      );
+    }
+  },
+
+  'when missing some options': {
+    topic: function() {
+      var setup = setupLogging('myLogger', {
+        "host": "127.0.0.1",
+        "port": 10001,
+        "type": "logstashUDP",
+        "category": "myLogger",
+        "layout": {
+          "type": "pattern",
+          "pattern": "%m"
+        }
+      });
+      setup.logger.log('trace', 'Log event #1');
+      return setup;
+    },
+    'it sets some defaults': function (topic) {
+      var json = JSON.parse(topic.results.buffer.toString());
+      assert.equal(json.type, 'myLogger');
+      assert.equal(JSON.stringify(json.fields), JSON.stringify({'level': 'TRACE'}));
+    }
+  }
+}).export(module);