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Application events

Application events lets you hook your serverless functions to external events.

Available event types are:

  • REST API route events
  • Background Job cron and scheduled events
  • Worker Queue events
  • Authentication events

The event hooks is an Node.js Express style JavaScript library in a public npm library that you install as a npm package in your project directory. You can check for updates in the npm version. 

npm install codehooks-js --save

API quick overview

Complete code example​

Import the app library in your application and hook into the various events.

import {app} from 'codehooks-js'

// generic serverless function
function fooFunc(req, res) {
    res.end()
}
// generic middleware function
function fooMiddleware(req, res, next) {
    next()
}

/* 
* Hook into events
*/
app.use(fooMiddleware); // global middleware
app.use('/foo', fooMiddleware); // global middleware on routes
app.get('/foo', fooFunc); // GET
app.post('/foo', fooFunc); // POST
app.put('/foo', fooFunc); // PUT
app.patch('/foo', fooFunc); // PATCH
app.delete('/foo', fooFunc); // DELETE
app.all('/foo', fooFunc); // GET, POST, PUT, PATCH, DELETE
app.auth('/*', fooMiddleware); // Called before outher routes without access tokens
app.job('* * * * *', fooFunc); // subscribe to cron events
app.worker('workername', fooFunc); // subscribe to worker events

// Bind events and functions to the serverless runtime
export default app.init();

app.init()​

Mandatory call to bind your functions to events from the serverless runtime.

Parameters none

app.use(workerFunction)​

Adds global middleware to all route API events (get, put, post, patch, delete).

Parameters

Returns void

Code example

import {app} from 'codehooks-js'
import cookieParser from 'cookie-parser'

// external npm lib middleware
app.use(cookieParser())

app.get('/foo', function (req, res) {
  // Cookies that have not been signed
  console.log('Cookies: ', req.cookies)

  // Cookies that have been signed
  console.log('Signed Cookies: ', req.signedCookies)

  // Custom middleware result
  console.log('Foo: ', req.foo)

  res.send('Done')
})

export default app.init();

app.use(route, workerFunction)​

Adds global middleware to a specific route API events (get, put, post, patch, delete).

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

// custom
app.use('/foo', (req, res, next) => {
    console.log('Called before any other route handlers')
    req.foo = 'Foo was here!'
    next() // must be called to continue
}) 

app.get('/foo', function (req, res) {
  // Custom middleware result
  console.log('Foo: ', req.foo)
  res.send('Done')
})

export default app.init();

app.get(route, workerFunction)​

Execute workerFunction function on HTTP GET method and route match.

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

app.get('/foo', function (req, res) {
  res.send('Done')
})

export default app.init();

app.post(route, workerFunction)​

Execute workerFunction function on HTTP POST method and route match.

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

app.post('/foo', function (req, res) {
    console.log("Data from client is", req.body)
    res.send('Done')
})

export default app.init();

app.put(route, workerFunction)​

Execute workerFunction function on HTTP PUT method and route match.

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

app.put('/foo', function (req, res) {
    console.log("Data from client is", req.body)
    res.send('Done')
})

export default app.init();

app.patch(route, workerFunction)​

Execute workerFunction function on HTTP PATCH method and route match.

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

app.patch('/foo', function (req, res) {
    console.log("Data from client is", req.body)
    res.send('Done')
})

export default app.init();

app.delete(route, workerFunction)​

Execute workerFunction function on HTTP DELETE method and route match.

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

app.delete('/foo/:ID', function (req, res) {
    const {ID} = req.params;
    console.log("Delete this", ID)
    res.send('Done')
})

export default app.init();

app.all(route, workerFunction)​

If no other routes matched before this, then execute the workerFunction function on all HTTP methods and route match.

Parameters

Returns void

Code example

import {app} from 'codehooks-js'

app.get('/foo', function (req, res) {
    res.send('Done GET')
})

app.all('/*', function (req, res) {
    res.send(`None of the above routes matched but this ${req.method} ${req.originalUrl}`)
})

export default app.init();

app.auth(route, workerFunction)​

Execute workerFunction function when no authentication token (x-apikey or JWT) is present. Works for all HTTP methods and route matches.

Parameters

Returns void

Code example

See Auth hooks docs here.

app.worker(name, workerFunction)​

Register a named workerFunction function that can be used to process queued events or scheduled events.

Parameters

  • name: unique worker name
  • workerFunction: function(queueData, responseFunction)

Returns void

Code example for queue workers

See Queue docs here.

Code example for scheduled workers

See scheduled jobs docs here.

app.job(cronExpression, workerFunction)​

Execute workerFunction function when cron job are scheduled.

Parameters

  • cronExpression: a valid cron expression string
  • workerFunction: function(jobData, responseFunction)

Returns void

Code example

See Job hook docs here.