Palin

Palin is a beautiful Bristol formatter for development logging.

Preview

Use

Install with npm install palin --save

Please remember to star ⭐️ this repo!

const log = require('bristol');
const palin = require('palin');
log.addTarget('console').withFormatter(palin);

log.info("We're up and running!");

One of Palin's main features is the ability to log whatever you throw at it. For example, you may want to log two Errors and other associated data.

const err1 = new Error('Error 1');
const err2 = new Error('Error 2');
log.error('oh, snap!', err1, err2, [ 'thing', 123 ])

Produces:

23:00:46:035 ERROR oh, snap! (test/integration.js:16)
  →  { '0': 'thing', '1': 123 }
  →  Error: Error 1
  →      at Object.<anonymous> (/Users/Mark/projects/palin/test/integration.js:14:12)
  →      at Module._compile (module.js:425:26)
  →      at Object.Module._extensions..js (module.js:432:10)
  →      at Module.load (module.js:356:32)
  →      at Function.Module._load (module.js:313:12)
  →      at Function.Module.runMain (module.js:457:10)
  →      at startup (node.js:138:18)
  →      at node.js:974:3
  →  Error: Error 2
  →      at Object.<anonymous> (/Users/Mark/projects/palin/test/integration.js:15:12)
  →      at Module._compile (module.js:425:26)
  →      at Object.Module._extensions..js (module.js:432:10)
  →      at Module.load (module.js:356:32)
  →      at Function.Module._load (module.js:313:12)
  →      at Function.Module.runMain (module.js:457:10)
  →      at startup (node.js:138:18)
  →      at node.js:974:3

API

Formatter Options

As per the Bristol logger API, you may specify options for formatters.

log
  .addTarget('console')
  .withFormatter(palin, {
    // formatter options go here
  });

Root Folder

Palin logs the file path where log messages originate from. Usually these paths are needlessly long. The rootFolderName option allows you to specify a string prefix of where to shorten the path.

log
  .addTarget('console')
  .withFormatter(palin, {
    rootFolderName: 'MyProject'
  });
  // produces log messages like:
  //  08:54:25:892 LOG hello (controller/hello.js:9)
  // instead of:
  //  08:54:25:892 LOG hello (/Users/Mark/projects/MyProject/controller/hello.js:9)

Timestamp

Palin logs timestamps in the "HH:mm:ss:SSS" format by default. You may want your timestamps to be different. This can be controlled with the timestamp option.

You can disable timestamps:

log
  .addTarget('console')
  .withFormatter(palin, {
    timestamp: false
  });

You can also provide your own timestamp function (shown with Moment.js):

var moment = require('moment'); // using moment.js
log
  .addTarget('console')
  .withFormatter(palin, {
    timestamp: function(date) {
        return moment(date).format(); // produces moment's default format
    }
  });

Indent

Any information that is attached to a log message is indented and included on the next line. The indentation format can be controlled with the indent option.

log
  .addTarget('console')
  .withFormatter(palin, {
    indent: '\n    ⇒  '
  });

Object Depth

Palin formats objects using the built-in require('util').inspect(). Use the objectDepth option to increase depth of each object printed.

log
  .addTarget('console')
  .withFormatter(palin, {
    objectDepth: 5 // instead of inspect's default level ( usually 2 )
  });

Source

Hide the source line/file of messages. Useful for logging purely informational messages.

log
  .addTarget('console')
  .withFormatter(palin, {
    souce: false
  });

Other features

Palin supports the concept of a "scope", which is a way of labeling groups of log messages. To use this, simply add an object with the key scope to the list of arguments. The color of the scope variable will be maintained for the lifetime of the the Bristol logger.

log.info('hello world', { scope: 'welcome' });
// produces:
// 08:54:25:892 INFO controller welcome (controller/hello.js:9)