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

   1 'use strict';
   2
   3 const internals = {
   4   kCircularString: '[Circular]',
   5   kAnsiCodes: {
   6     bold: '[1m',
   7     italics: '[3m',
   8     underline: '[4m',
   9     inverse: '[7m',
  10     strikethrough: '[9m',
  11     bold_off: '[22m',
  12     italics_off: '[23m',
  13     underline_off: '[24m',
  14     inverse_off: '[27m',
  15     strikethrough_off: '[29m',
  16     black: '[30m',
  17     red: '[31m',
  18     green: '[32m',
  19     yellow: '[33m',
  20     blue: '[34m',
  21     magenta: '[35m',
  22     cyan: '[36m',
  23     white: '[37m',
  24     default: '[39m',
  25     black_bg: '[40m',
  26     red_bg: '[41m',
  27     green_bg: '[42m',
  28     yellow_bg: '[43m',
  29     blue_bg: '[44m',
  30     magenta_bg: '[45m',
  31     cyan_bg: '[46m',
  32     white_bg: '[47m',
  33     default_bg: '[49m',
  34     reset: '[0m'
  35   },
  36
  37   // Get High Res time depending on platform. Currently only supporting node.
  38
  39   getHighResTime() {
  40
  41     return process.hrtime.bigint();
  42   }
  43 };
  44
  45 // Initialise relative time.
  46
  47 internals.initialTimestamp = BigInt(Date.now()) * 1000000n;
  48 internals.initialHighResTime = internals.getHighResTime();
  49
  50 /**
  51  * Container object for utilities used by loggers.
  52  *
  53  * @class Utilities
  54  */
  55 module.exports = {
  56
  57   /**
  58    * Returns the current timestamp in nanoseconds as a bigint.
  59    *
  60    * @function now
  61    * @memberof Utilities
  62    * @return {bigint} current time in nanoseconds, including fractions.
  63    */
  64   now() {
  65
  66     return internals.initialTimestamp + internals.getHighResTime() - internals.initialHighResTime;
  67   },
  68
  69   /**
  70    * Stringifies objects, avoiding circular references.
  71    *
  72    * @function stringify
  73    * @memberof Utilities
  74    * @param {Object} object the object to stringify
  75    * @return {String} the stringified object
  76    */
  77   stringify(object) {
  78
  79     const cache = new Set();
  80
  81     return JSON.stringify(object, (key, value) => {
  82
  83       if (typeof value === 'bigint') {
  84         return String(value) + 'n';
  85       }
  86
  87       if (typeof value === 'object' && value !== null) {
  88         if (cache.has(value)) {
  89           return internals.kCircularString;
  90         }
  91
  92         cache.add(value);
  93       }
  94
  95       return value;
  96     });
  97   },
  98
  99   /**
 100    * Given an ansi keyword, it will return the appropriate code.
 101    *
 102    * @function getAnsiCode
 103    * @memberof Utilities
 104    * @param {String} ansiString the name of the desired code
 105    * @return {String} the ansi code
 106    */
 107   getAnsiCode(ansiString) {
 108
 109     return internals.kAnsiCodes[ansiString] || internals.kAnsiCodes.reset;
 110   },
 111
 112   /**
 113    * Given a level, it will return the appropriate ansi keyword related
 114    * to it.
 115    *
 116    * @function getLevelAnsi
 117    * @memberof Utilities
 118    * @param {number} level the level of the log
 119    * @return {String} the ansi keyword
 120    */
 121   getLevelAnsi(level) {
 122
 123     switch (level) {
 124     case 0:
 125     case 1:
 126     case 2:
 127     case 3:
 128       return 'red';
 129     case 4:
 130       return 'yellow';
 131     case 5:
 132     case 6:
 133       return 'blue';
 134     case 7:
 135       return 'green';
 136     default:
 137       return 'default';
 138     }
 139   }
 140 };