Source: common/logger.js

  1. 'use strict';
  2. /**
  3.  * @module lib/common/logger
  4.  * @summary Whiteflag API logging module
  5.  * @description Module for logging events of the Whiteflag API
  6.  * @tutorial modules
  7.  * @tutorial logging
  8.  */
  9. module.exports = {
  10.     // Loglevel functions
  11.     setLogLevel,
  12.     getLogLevel,
  13.     // Logging functions
  14.     fatal,
  15.     error,
  16.     warn,
  17.     info,
  18.     debug,
  19.     trace
  20. };
  22. // Module constants //
  23. /**
  24.  * @constant {Object} levels
  25.  * @description Defines the logging levels
  26.  */
  27. const levels = {
  28.     fatal: 1,
  29.     error: 2,
  30.     warn: 3,
  31.     info: 4,
  32.     debug: 5,
  33.     trace: 6
  34. };
  35. // Module variables //
  36. let _logLevel = 4;
  38. // MAIN MODULE FUNCTIONS //
  39. /**
  40.  * Sets new logging level
  41.  * @function setLogLevel
  42.  * @alias module:lib/common/logger.setLogLevel
  43.  * @param {loglevel} loglevel logging level to be set
  44.  * @param {function(Error, loglevel)} callback
  45.  * @typedef {number} loglevel logging level
  46.  */
  47. function setLogLevel(level, callback) {
  48.     if (level > 0 && level <= 6) {
  49.         _logLevel = level;
  50.     } else {
  51.         return callback(new Error(`Logging level ${level} does not exist`), _logLevel);
  52.     }
  53.     return callback(null, _logLevel);
  54. }
  56. /**
  57.  * Returns current loglevel
  58.  * @function getLogLevel
  59.  * @alias module:lib/common/logger.getLogLevel
  60.  * @param {function(Error, loglevel)} callback
  61.  */
  62. function getLogLevel(callback) {
  63.     return callback(null, _logLevel);
  64. }
  66. // MAIN LOGGER FUNCTIONS
  67. /**
  68.  * Logs fatal events (level 1)
  69.  * @function fatal
  70.  * @alias module:lib/common/logger.fatal
  71.  * @param {string} module name of the module that makes the log
  72.  * @param {string} message the message to log
  73.  */
  74. function fatal(module, message) {
  75.     if (levels.fatal <= _logLevel) {
  76.         return console.error(`[FATAL] ${module}: ${message}`);
  77.     }
  78. }
  80. /**
  81.  * Logs error events (level 2)
  82.  * @function error
  83.  * @alias module:lib/common/logger.error
  84.  * @param {string} module name of the module that makes the log
  85.  * @param {string} message the message to log
  86.  */
  87. function error(module, message) {
  88.     if (levels.error <= _logLevel) {
  89.         return console.error(`[ERROR] ${module}: ${message}`);
  90.     }
  91. }
  93. /**
  94.  * Logs warning events (level 3)
  95.  * @function warn
  96.  * @alias module:lib/common/logger.warn
  97.  * @param {string} module name of the module that makes the log
  98.  * @param {string} message the message to log
  99.  */
  100. function warn(module, message) {
  101.     if (levels.warn <= _logLevel) {
  102.         return console.warn(`[WARN ] ${module}: ${message}`);
  103.     }
  104. }
  106. /**
  107.  * Logs informational events (level 4)
  108.  * @function info
  109.  * @alias module:lib/common/logger.info
  110.  * @param {string} module name of the module that makes the log
  111.  * @param {string} message the message to log
  112.  */
  113. function info(module, message) {
  114.     if (levels.info <= _logLevel) {
  115.         return console.info(`[INFO ] ${module}: ${message}`);
  116.     }
  117. }
  119. /**
  120.  * Logs debug events (level 5)
  121.  * @function debug
  122.  * @alias module:lib/common/logger.debug
  123.  * @param {string} module name of the module that makes the log
  124.  * @param {string} message the message to log
  125.  */
  126. function debug(module, message) {
  127.     if (levels.debug <= _logLevel) {
  128.         return console.debug(`[DEBUG] ${module}: ${message}`);
  129.     }
  130. }
  132. /**
  133.  * Logs trace events (level 6)
  134.  * @function trace
  135.  * @alias module:lib/common/logger.trace
  136.  * @param {string} module name of the module that makes the log
  137.  * @param {string} message the message to log
  138.  */
  139. function trace(module, message) {
  140.     if (levels.trace <= _logLevel) {
  141.         return console.debug(`[TRACE] ${module}: ${message}`);
  142.     }
  143. }