Merge branches 'package-json-files', 'timestamp-with-timezone' and 'unit-tests'

Author: LeartS

README.md

@@ -53,7 +53,7 @@ const log = require('monk-log')
 log.warn('You can have nice log messages in just one line!')
 
 // Outputs
-// [2019-02-18T01:10:49.933] WARN [root]: You can have nice log messages in just one line!
+// [2019-02-18T01:10:49.933+01:00] WARN [root]: You can have nice log messages in just one line!
 ```
 
 ### Child loggers with custom format
@@ -73,8 +73,8 @@ childLogger.error('this is an error message')
 
 // Outputs
 // [2019-02-18T01:08:46.260] INFO [root]: Child logger has been set up
-// When: 2019-02-18T01:08:46.262, who: CHILD, why: DEBUG, what: this is a debug message
-// When: 2019-02-18T01:08:46.262, who: CHILD, why: INFO, what: This is a info message
-// When: 2019-02-18T01:08:46.262, who: CHILD, why: WARN, what: this is a warning message
-// When: 2019-02-18T01:08:46.263, who: CHILD, why: ERROR, what: this is an error message
+// When: 2019-02-18T01:08:46.262+01:00, who: CHILD, why: DEBUG, what: this is a debug message
+// When: 2019-02-18T01:08:46.262+01:00, who: CHILD, why: INFO, what: This is a info message
+// When: 2019-02-18T01:08:46.262+01:00, who: CHILD, why: WARN, what: this is a warning message
+// When: 2019-02-18T01:08:46.263+01:00, who: CHILD, why: ERROR, what: this is an error message
 ```

lib/log.js

@@ -12,12 +12,35 @@ const colors = Object.freeze({
   ERROR: chalk.red
 })
 
-const defaultTimestampFormatter = (date) => {
-  const tzOffset = date.getTimezoneOffset() * 60000 // offset in milliseconds
-  const localISOTime = (new Date(date - tzOffset)).toISOString().slice(0, -1) // => '2015-01-26T06:40:36.181'
-  return localISOTime
+/**
+ * Converts a date to the RFC3339 profile of the ISO 8601 standard
+ *
+ * Example: 2019-02-08T19:02:09.432+01:00
+ * https://tools.ietf.org/html/rfc3339#section-5.6
+ *
+ * Inspired by https://stackoverflow.com/a/17415677/1362167
+ */
+const dateToISOString = (d, milliseconds = true) => {
+  // Pad an integer >=0, <= 99 to 2 digits.
+  // Useful to pad days, minutes, hours, months etc.
+  const pad2 = num => `${num < 10 ? '0' : ''}${num}`
+  const pad3 = num => `${num < 100 ? (num < 10 ? '00' : '0') : ''}${num}`
+  const offset = -d.getTimezoneOffset()
+  const absOffset = Math.abs(offset)
+  return d.getFullYear()
+    + '-' + pad2(d.getMonth() + 1)
+    + '-' + pad2(d.getDate())
+    + 'T' + pad2(d.getHours())
+    + ':' + pad2(d.getMinutes())
+    + ':' + pad2(d.getSeconds())
+    + (milliseconds ? ('.' + pad3(d.getMilliseconds())) : '')
+    + (offset >= 0 ? '+' : '-')
+    + pad2(Math.floor(absOffset / 60))
+    + ':' + pad2(absOffset % 60)
 }
 
+const defaultTimestampFormatter = dateToISOString
+
 const defaultNameFormatter = (name) => {
   return chalk.green(name)
 }
@@ -99,3 +122,6 @@ defaultLogger.getLoggers = () => _loggersByName
 // Export default logger. Can be used directly, or can be used
 // to obtain child loggers.
 module.exports = defaultLogger
+// Export dateToISOString, users may want to use it to define a custom
+// timestampformatter
+module.exports.dateToISOString = dateToISOString