express-promise-router

A simple wrapper for Express 4's Router that allows middleware to return promises. This package makes it simpler to write route handlers for Express when dealing with promises by reducing duplicate code.

Getting Started

Install the module with: npm install express-promise-router --save.

express-promise-router is a drop-in replacement for Express 4's Router.

Documentation

Middleware and route handlers can simply return a promise. If the promise is rejected, express-promise-router will call next with the reason. This functionality removes the need to explicitly define a rejection handler.

// With Express 4's router
var router = require('express').Router();

router.use('/url', function (req, res, next) {
    Promise.reject().catch(next);
})

// With express-promise-router
var router = require('express-promise-router')();

router.use('/url', function (req, res) {
    return Promise.reject();
})

Calling next() and next('route') is supported by resolving a promise with either 'next' or 'route'. No action is taken if the promise is resolved with any other value.

router.use('/url', function (req, res) {
    // equivalent to calling next()
    return Promise.resolve('next');
});

router.use('/url', function (req, res) {
    // equivalent to calling next('route')
    return Promise.resolve('route');
});

This package still allows calling next directly.

router = require('express-promise-router')();

// still works as expected
router.use('/url', function (req, res, next) {
    next();
});

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.

Release History

(Nothing yet)

License

Copyright (c) 2014 Alex Whitney. Licensed under the MIT license.