logging

The logging package provides a standardised way for you to log and display in console various message from your application. The added benefit is that among other data it will show you the location where the log was fired, this is useful during debugging to quickly locate where the message is coming from.

Start by installing the package:

meteor add logging

You can then import the utility anywhere in you code like this:

import { Log } from 'meteor/logging'

You can then call the logging functions in one of the following ways:

Log('starting up') // or Log.info('starting up')
Log.error('error message')
Log.warn('warning')
Log.debug('this will show only in development')

Besides passing in strings, you can also pass in objects. This has few exceptions and special functions associated. First in the root of the object the following keys are not allowed:

'time', 'timeInexact', 'level', 'file', 'line', 'program', 'originApp', 'satellite', 'stderr'

On the other hand there is message and app, which are also reserved, but they will display in more prominent manner:

Log.info({message: 'warning', app: 'DESKTOP', error: { property1: 'foo', property2: 'bar', property3: { foo: 'bar' }} })

will turn into:

E20200519-17:57:41.655(9) [DESKTOP] (main.js:36) warning {"error":{"property1":"foo","property2":"bar","property3":{"foo":"bar"}}}

The display of each log is color coded. Info is blue, warn is magenta, debug is green and error is in red.

Log.debug

The Log.debug() logging is different from the other calls as these messages will not be displayed in production.