Wrapp-log

NodeJS JSON producing logging library. See output details below for examples.

Requirements

NodeJS v7+

Installation

npm install wrapp-log

or

yarn add wrapp-log

Usage

API

• log.debug(msg, [options]) - Outputs the message with with level: debug
• log.info(msg, [options]) - Outputs the message with with level: info
• log.warning(msg, [options]) - Outputs the message with with level: warning
• log.error(msg, [options]) - Outputs the message with with level: error
• log.panic(msg, [options]) - Outputs the message with with level: panic then exits the process with status code 1

The msg argument is expected to be string but can be something else as well.

The options argument is required to be undefined or an object. Each value should be a primitive / JSON parsable object.

and error is passed in options as: { error: new Error() } and will be parsed. See "Output details" below for more info.

Input

const log = require('wrapp-log')
 
log.info('Informal message')

try {
  throw new Error('Cannot handle the overload...')
} catch (e) {
  log.error('Something seriously wrong', { error: e })
}

log.panic('Too much to handle')

Output

{"level":"info","msg":"Informal message","timestamp":"2017-06-07T14:02:40.759Z"}
{"error":{"name":"Error","message":"Cannot handle the overload...","stack":[{"fileName":"/Users/wrapp/test-logging.js","lineNumber":6,"functionName":null,"typeName":"Object","methodName":null,"columnNumber":9,"native":false},{"fileName":"module.js","lineNumber":571,"functionName":"Module._compile","typeName":"Module","methodName":"_compile","columnNumber":32,"native":false},{"fileName":"module.js","lineNumber":580,"functionName":"Module._extensions..js","typeName":"Object","methodName":".js","columnNumber":10,"native":false},{"fileName":"module.js","lineNumber":488,"functionName":"Module.load","typeName":"Module","methodName":"load","columnNumber":32,"native":false},{"fileName":"module.js","lineNumber":447,"functionName":"tryModuleLoad","typeName":null,"methodName":null,"columnNumber":12,"native":false},{"fileName":"module.js","lineNumber":439,"functionName":"Module._load","typeName":"Function","methodName":"_load","columnNumber":3,"native":false},{"fileName":"module.js","lineNumber":605,"functionName":"Module.runMain","typeName":"Module","methodName":"runMain","columnNumber":10,"native":false},{"fileName":"bootstrap_node.js","lineNumber":427,"functionName":"run","typeName":null,"methodName":null,"columnNumber":7,"native":false},{"fileName":"bootstrap_node.js","lineNumber":151,"functionName":"startup","typeName":null,"methodName":null,"columnNumber":9,"native":false},{"fileName":"bootstrap_node.js","lineNumber":542,"functionName":null,"typeName":null,"methodName":null,"columnNumber":3,"native":false}]},"level":"error","msg":"Something seriously wrong","timestamp":"2017-06-07T14:02:40.760Z"}
{"level":"panic","msg":"Too much to handle","timestamp":"2017-06-07T14:02:40.762Z"}

[Exited with code 1]

Output details

All output is performed to standard out. Nothing goes to standard error. Each log message is on one and the same line and a line break \n is added after each message.

The log output will look like the example below, but on one line only. Any additional properties will be added.

Errors are parsed to some extent (message, name and any attacked properties), and the error stack trace uses npm module stack-trace

{
  "level": "<debug|info|warning|error|panic>",
  "msg": "<log text>",
  "service":"<service name>",
  "timestamp": "<timestamp>",
  ["additional_properties": "some text| 123 | {\"deep\":\"stuff\"}"]
}