Updates winston-graylog2 to use winston@3.x

.eslintrc.json

@@ -7,7 +7,6 @@
   },
   "rules": {
     "quote-props": ["error", "as-needed"],
-    "new-cap": ["error", {"properties": false}], // TODO: remove once newcap errors are fixed.
     "quotes": ["error", "single", { "avoidEscape": true }],
     "max-len": [
       "error",
@@ -30,10 +29,7 @@
     ]
   },
   "parserOptions": {
-    "ecmaVersion": 6,
-    "sourceType": "module",
-    "ecmaFeatures": {
-      "experimentalObjectRestSpread": true
-    }
+    "ecmaVersion": 2018,
+    "sourceType": "module"
   }
 }

.gitignore

@@ -1,3 +1,4 @@
 node_modules
 .svn
-npm-debug.log
+npm-debug.log
+*.swp

.travis.yml

@@ -3,10 +3,10 @@ language: node_js
 sudo: false
 
 node_js:
-   - 6.10
+   - 6.4.0
 
 install:
-  - npm install --dev
+  - npm install
 
 script:
   - yarn lint

lib/winston-graylog2.js

@@ -1,18 +1,16 @@
 'use strict';
 
-const util = require('util');
-const winston = require('winston-transport');
-const graylog2 = require('graylog2');
-const _ = require('lodash');
+const Transport = require('winston-transport');
+const {graylog: Graylog2Client} = require('graylog2');
 
 /**
  * Remapping winston level on graylog
  *
  * @param  {String} winstonLevel
  * @return {String}
  */
-let getMessageLevel = (function() {
-  let levels = {
+const getMessageLevel = (function() {
+  const levels = {
     emerg: 'emergency',
     alert: 'alert',
     crit: 'critical',
@@ -28,86 +26,65 @@ let getMessageLevel = (function() {
   };
 })();
 
-/**
- * Preparing metadata for graylog
- * If we send a javascript `Error` object
- * to gray log we'll end up with the
- * `[object Object]` string.
- * To have our infos we need to get the stack out of the error.
- * Here we remap metadata to handle this kind of situation
- *
- * @param  {Object} meta
- * @param  {Object} staticMeta
- * @return {Object}
- */
-function prepareMeta(meta, staticMeta) {
-  meta = meta || {};
-
-  if (meta instanceof Error) {
-    meta = {error: meta.stack};
-  } else if (typeof meta === 'object') {
-    meta = _.mapValues(meta, function(value) {
-      if (value instanceof Error) {
-        return value.stack;
-      }
-
-      return value;
+/** Class representing the Graylog2 Winston Transport */
+class Graylog2 extends Transport {
+  /**
+   * Create the transport
+   * @param {Object} options - The options for configuring the transport.
+   */
+  constructor(options) {
+    super(options);
+
+    options = options || {};
+    this.graylog = options.graylog;
+    if (!this.graylog) {
+      this.graylog = {
+        servers: [
+          {
+            host: 'localhost',
+            port: 12201,
+          },
+        ],
+      };
+    }
+
+    this.name = options.name || 'graylog2';
+    this.exceptionsLevel = options.exceptionsLevel || 'not-default';
+
+    this.silent = options.silent || false;
+    this.handleExceptions = options.handleExceptions || false;
+
+    this.graylog2Client = new Graylog2Client(this.graylog);
+    this.staticMeta = options.staticMeta || {};
+
+    this.graylog2Client.on('error', function(error) {
+      console.error('Error while trying to write to graylog2:', error);
     });
   }
 
-  meta = _.merge(meta, staticMeta);
-
-  return meta;
-}
-
-let Graylog2 = (winston.Graylog2 = function(options) {
-  winston.call(this, options);
-
-  options = options || {};
-  this.graylog = _.get(options, 'graylog');
-  if (!this.graylog) {
-    this.graylog = {
-      servers: [
-        {
-          host: 'localhost',
-          port: 12201,
-        },
-      ],
-    };
+  /**
+   * Log a message to Graylog2.
+   *
+   * @param {Object} info - An object containing the `message` and `info`.
+   * @param {function} callback - Winston's callback to itself.
+   */
+  log(info, callback) {
+    const {message, level, metadata} = info;
+    const meta = Object.assign({}, metadata, this.staticMeta);
+
+    // prettier-ignore
+    setImmediate(() => {
+      this.graylog2Client[getMessageLevel(level)](message.substring(0, 100), message, meta);
+    });
+    callback();
   }
 
-  this.name = options.name || 'graylog2';
-  this.exceptionsLevel = options.exceptionsLevel || 'not-default';
-
-  this.silent = options.silent || false;
-  this.handleExceptions = options.handleExceptions || false;
-  this.prelog =
-    typeof options.prelog === 'function' ? options.prelog : _.identity;
-  this.processMeta =
-    typeof options.processMeta === 'function'
-      ? options.processMeta
-      : _.identity;
-  this.staticMeta = options.staticMeta || {};
-
-  this.graylog2 = new graylog2.graylog(this.graylog); // TODO: Fix in relation to https://eslint.org/docs/rules/new-cap
-
-  this.graylog2.on('error', function(error) {
-    console.error('Error while trying to write to graylog2:', error);
-  });
-});
-
-util.inherits(Graylog2, winston);
-
-Graylog2.prototype.log = function(level, msg, meta, callback) {
-  meta = this.processMeta(prepareMeta(meta, this.staticMeta));
-  msg = this.prelog(msg);
-
-  this.graylog2[getMessageLevel(level)](msg.substring(0, 100), msg, meta);
-  callback(null, true);
-};
-
-Graylog2.prototype.close = function() {
-  this.graylog2.close();
-};
+  /**
+   * Closes the Graylog2 Winston Transport.
+   */
+  close() {
+    this.graylog2Client.close();
+  }
+}
 
 module.exports = Graylog2;