git.r.bdr.sh - rbdr/cologne/blob - lib/formatters/token.js

   1 'use strict';
   2
   3 const Utilities = require('../utilities');
   4
   5 /**
   6  * Token formatter. Given a format string it will attempt to output
   7  * a message.
   8  *
   9  * @memberof Formatters
  10  * @implements IFormatter
  11  * @class Token
  12  */
  13 module.exports = class TokenFormatter {
  14   constructor(config) {
  15
  16     /**
  17      * The string to use as a template string. By default, any property
  18      * inside double curly braces `{{likeThis}}` will be extracted from
  19      * the object and replaced. If the object does not contain the
  20      * property, it will leave it.
  21      *
  22      * @name formatString
  23      * @instance
  24      * @memberof Formatters.Token
  25      * @type String
  26      * @default '{{message}}'
  27      */
  28     this.formatString = '{{message}}';
  29
  30     /**
  31      * The regex rule to use to match the tokens.
  32      *
  33      * @name replaceRule
  34      * @instance
  35      * @memberof Formatters.Token
  36      * @type RegExp
  37      * @default /{{(.{1,255}?)}}/g
  38      */
  39     this.replaceRule = /{{(.{1,255}?)}}/g;
  40
  41     /**
  42      * Flag that specifies whether or not to use an isoDate when using
  43      * `_timestamp`. If false it will output the raw timestamp.
  44      *
  45      * @name isoDate
  46      * @instance
  47      * @memberof Formatters.Token
  48      * @type Boolean
  49      * @default true
  50      */
  51     this.isoDate = true;
  52
  53     this._ansiRe = /_ansi:.+/;
  54
  55     Object.assign(this, config || {});
  56   }
  57
  58   /**
  59    * Main entry point, it will read the incoming log object and convert
  60    * all the tokens to their corresponding representation, finally
  61    * returning the string.
  62    *
  63    * @function format
  64    * @instance
  65    * @memberof Formatters.Token
  66    * @param {tCologneLog} log the log to format
  67    * @return {String} the formatted object
  68    */
  69   format(log) {
  70
  71     const escapeCode = String.fromCharCode(27);
  72     return this.formatString.replace(this.replaceRule, (match, token) => {
  73
  74       if (token === '_timestamp' && this.isoDate) {
  75         const date = new Date(Number(log._timestamp) / 1000000);
  76         return date.toISOString();
  77       }
  78
  79       if (token.match(this._ansiRe)) {
  80         const ansiType = token.split(':')[1];
  81
  82         // Smartish coloring
  83         if (ansiType === '_level') {
  84           return escapeCode + Utilities.getAnsiCode(Utilities.getLevelAnsi(log._level));
  85         }
  86
  87         return escapeCode + Utilities.getAnsiCode(ansiType);
  88       }
  89
  90       return log[token] || match;
  91     });
  92   }
  93 };