@gradientedge/logger

Usage

This package is only intended for use within a node environment.

Using the default logger instance

You don't need to create any objects in order to start logging. It's as simple as:

import log from '@gradientedge/logger'

log.debug('Your message here', { additionalData: 123 })

The log object here is a singleton that's created when the @gradientedge/logger package is first imported.

Creating your own logger instance

If you want more control over the creation of the Logger instance, you can create your own:

import { Logger, LoggerLevel } from '@gradientedge/logger'

const myLogger = new Logger({
  level: LoggerLevel.ERROR,
})

myLogger.error('Major problem!')

Using with @gradientedge/als

The @gradientedge/als is a simple suite of functions that allow you to create AsyncLocalStorage via the create function, and then retrieve that data via the retrieve function.

As you'll see in the index.ts file, we use JavaScript's Proxy class to check to see if we have async local storage data available to us each time any of the Logger methods are called. If we do, then we check for logger property on that data object. If that exists, and is an instance of Logger, then we call the log method on that Logger instance rather than on the singleton instance.

Here's an example:

import { Logger, LoggerLevel } from '@gradientedge/logger'

const myLogger = new Logger({
  level: LoggerLevel.WARN,
  baseData: {
      requestId: '1234'
  }
})

const context = {
  logger: myLogger
}

als.create(context, async () => {
  
  log.debug('Test message', { name: 'Jimmy' })
  
  // Prints the following:
  //
  // {
  //   "level": "debug",
  //   "message": "Test message",
  //   "base": {
  //     "requestId": "1234"
  //   },
  //   "data": {
  //     "name": "Jimmy"
  //   }
  // }
})

Setting the log level with an environment variable

You can define a LOGGER_LEVEL environment variable with one of the following values:

• debug
• info
• warn
• error

If set, this will be used as the default log level for any new instances of the Logger class.