Promise Router Monitor

Check your promise execution timeout or not. If it execution taking to long you can cancel it and log it.

Wrap express router for auto catch error or unhandled promise rejection. So you don't need to use try catch in your express middleware/controller, or wrap your every express middleware/controller. Just using single wrap for express router.

Installation

• Yarn

yarn add express promise-router-monitor

• Npm

npm i --save express promise-router-monitor

Example

const express = require('express');
const axios = require('axios');
const { EventEmitter } = require('events');
const { guardPromise, Router } = require('promise-router-monitor');

/** Create event emitter to monitor/log timeout or rejected promise that wrapped with guardPromise */
const emitterPromise = new EventEmitter();
emitterPromise.on('timeout', ({ promise, message }) => {
  console.log(message);
})

emitterPromise.on('reject', ({ promise, message, err }) => {
  console.log(message);
  console.log(err);
})

/** Util function to delay promise execution */
const delayPromise = (promise, time) => new Promise((resolve, reject) => setTimeout(() => {
  resolve(promise)
}, time));

const app = express();
app.set('env', 'development')

/** Instantiate new express router with Router */
const exampleRouter = new Router();
exampleRouter.get('/limit',
  async (req, res) => {
    const url = 'https://api.chucknorris.io/jokes/random'
    const url1 = 'http://http://bugr.or.id/'
    const axiosGetPromise = delayPromise(axios.get(url), 1000)

    /**
     * Object parameter for guardPromise
     * @param  {Promise} {promise
     * @param  {integer} time in millisecond
     * @param  {string} location}
     */
    const props = { promise: axiosGetPromise, time: 3000, location: `'axiosDelayPromise' in ${__filename}` }

    /** guardPromise with emitterPromise and object parameter */
    const data = await guardPromise(emitterPromise)(props)

    res.json({
      status: true,
      code: 200,
      message: 'Success',
      data: data.data || data,
    })
  },
)

/** Get the original express router */
app.use('/', exampleRouter.getOriginal());

/** Not found handler */
app.use((req, res, next) => {
  const err = new Error('URL Not Found')
  err.httpStatus = 404
  next(err)
});

/** Development error handler */
if (app.get('env') === 'development') {
  app.use((err, req, res, next) => {
    const { start, httpStatus, message, previousError, stack } = err
    res.status(httpStatus || 406).json({
      status: false,
      code: httpStatus || 406,
      message,
      data: previousError,
      error: stack
    })
  })
}

/** Production error handler */
app.use((err, req, res, next) => {
  const { start, httpStatus, previousError, stack } = err
  const message = (httpStatus === 500) ? 'Internal Server Error' : err.message
  res.status(httpStatus || 406).json({
    status: false,
    code: httpStatus || 406,
    message,
    data: previousError,
  })
})

app.listen(5000, () => {
  console.log('Running on port 5000')
})