woodwork-logger

Table of Contents

• Install
• Example
  • Basic
  • Recommended
• API

Install

npm install woodwork-logger

Example

Basic

const woodwork = require('woodwork-logger');

const logger = woodwork.create('service-a', {
  // This is where you make use of whatever client you
  // have as a dependency to make requests.
  //
  // The following code below is just an example when using e.g. Axios.
  // It's also wise to make use of `navigator.sendBeacon` if available
  // to ensure the request is sent before e.g. redirecting a user
  request: (events) => {
    if (typeof navigator.sendBeacon !== 'undefined') {
      navigator.sendBeacon(`http://backend-service`, JSON.stringify({ events }));
    } else {
      axios.post('http://backend-service', { events });
    }
  },
});

// > Request will be sent every 10th second IF there are events and along with all gathered events during that period
logger.info('Logger initialized');

// > Request is sent immediately along with any events gathered so far
const error = new Error('big bang')
logger.error('Something terrible happened', { error });

// Example payload to service
{
  events: [
    {
      clientId: 'xei3zzhaf', // Random id created by woodwork-logger on initialization
      data: {
        error: {
          message: 'big bang',
          name: 'Error',
          stack: 'Error: big bang ...',
        },
      },
      event: 'Something terrible happened',
      level: 'error',
      service: 'service-a',
    },
  ],
}

Recommended

Create a separate file where you import the logger, create and exports the instance to be used throughout the project.

Import the logger as early as possible in your frontend project, no need to assign it, but we want it initialized.

// logger.js
const woodwork = require('woodwork-logger');

const logger = woodwork.create('service-a', {
  request: (events) => {
    if (typeof navigator.sendBeacon !== 'undefined') {
      navigator.sendBeacon(`http://backend-service`, JSON.stringify({ events }));
    } else {
      // any client of your choice
    }
  },
});

module.exports = logger;

In any other file

// some-component.js
const logger = require('./path/to/logger.js');

logger.info('aw yiss');

API

woodwork

woodwork.create(name: String, options: Object): WoodworkLogger instance

Creates a new instance of woodwork-logger.

name

The name of the frontend service which you are creating the logger for.

options.clientId: String

By default the logger will create a unique anonymous id for the current client, but in the case where you have retrieved the already created id from example a cookie then you can avoid generating a new one and instead keep using the old id for the user by passing it.

options.interceptors: Array

An array of "interceptors" that will be run per event logged, from left-to-right or top-to-bottom.

This is for when you need to transform your events before they are passed dispatched to the backend server, one example is woodwork-interceptor-error which looks for an Error object and exposes non-enumerable props to be sent to the backend that would otherwise not be sent.

options.request: Function(events: Array)

It's up to you how you wish to send your logs to the backend. This function is called when dispatching logs and it's here where you make the request with the client of your choice. In the examples above axios was used.

woodwork.get(name: String): WoodworkLogger instance

Retrieves an already created instance of woodwork-logger.

woodwork.flush(): void

Is called every 10th second. If an error-log is dispatched it will call this function automatically along with any other events that has gathered since the last dispatch.