Express.js Manifold

An express switch to host multiple express apps on one server.

• Installation
• Usage
  • manifold(domains)
  • switcher.listen([httpPort[, httpsPort[, host[, backlog]]]][, callback])
• Examples
  • Simple setup
  • The switcher object
  • HTTP over TLS (HTTPS)

Installation

npm i express-manifold

Usage

Multiple domains may point to one IP address. With a normal express.js server you would then have to serve the same web-app / website to all domains pointing to that server. With express-manifold however, you can route different web-apps / websites over the same IP address to different domains.

manifold(domains)

manifold(domains) where domains is a JavaScript object with the domains of the server as the keys, and either an express app, or a configuration object as the value.
If given an express app, this app will only listen on the first port given ( see switcher.listen).
If given a configuration object, it must follow the following structure.

| Field | Type | Description | Required | Default | |---|---|---|---|---| | server | express app | The app for the given domain | yes | - | | httpsServer | express app | Another app, if you want to have a different app for https. If not given, the server value will be used. | no | - | | cert | string|buffer | The certificate in PEM format for the given domain. | only if forceHttpsis true | - | | key | string|buffer | The private keys in PEM format for the given domain. | only if forceHttpsis true | - | | selfSigned | boolean | Whether the certificate given is self-signed or not. Should be false or omitted during production. | no | false | | preferHttps | boolean | Will redirect http to https if Upgrade-Insecure-Requests is set to "1", and certificate and private keys are provided. | no | true | | forceHttps | boolean | Will always redirect http to https, regardless of the preferHttps mechanism. | no | false |

The server given for server will listen on both the first, and the second port, except if httpsServer is given. Then, the server given for server will listen on the first port and server given for httpsServer will listen on the second port.

This function returns an express server switcher which acts like an appended server. That means if you .get() a path that a server on a given domain does not handle, it will fallback to that function. (see examples for examples)

switcher.listen([httpPort[, httpsPort[, host[, backlog]]]][, callback])

The returned switcher's functions behave the same as in a normal express app, except for the .listen() function. Instead of using one port it will use two.

• The first port is meant to be the HTTP-port, and is used for all given servers for server. In production this should be 80.
• The second port is meant to be the HTTPS-port, and is used for all given servers for httpsServer. In production this should be 443.

If one of both are omitted / undefined, an arbitrary, unused port will be assigned.

Similar to express().listen, this function returns the created http/s server as an array where the first value is the http server, and the second value is the https server.

Examples

You can see a simple example in example/twofold.js. To run it you have to follow a couple steps (included in the file) .

Simple setup

Create multiple express server / nodejs server and assign them to a domain like so:

const express = require('express')
const manifold = require('express-manifold')

// create your express apps (or import them from another file)
const exampleApp = express()
const anotherApp = express()

exampleApp.get('/', (req, res) => {
    res.send('Hello World!').end()
})

anotherApp.get('/', (req, res) => {
    res.send('Hello World!').end()
})

// assign all apps to their domains
// you can also assingn one app to multiple domains
const switcher = manifold({
    "example.com": exampleApp,
    "another-example.com": anotherApp
})

switcher.listen(80)

The switcher object

The switcher object itself acts just like an express app. That means that after you assigned your domains, you can add fallback logic:

/*[...]*/

const switcher = manifold({
    "example.com": exampleApp,
    "another-example.com": anotherApp
})

// use the returned switcher to add a fallback mechanism to all given servers
switcher.use((req, res) => {
    res.status(404).end()
})

switcher.listen(80)

HTTP over TLS (HTTPS)

For https you have to pass a configuration object for the domain in question. Similar to the https.createServer options, pass the certificate in pem format as cert and the key (also in pem format) as key. Finally, add a second port to the switcher.listen function. For more info, see Usage.

/*[...]*/

const switcher = manifold({
    "example.com": {
        server: exampleApp,
        // feed your certfifcate and key like this
        cert: fs.readFileSync("path/to/certificate.crt"),
        key: fs.readFileSync("path/to/key.key"),
        // set "selfSigned" to true if your certificate is self signed
        // selfSigned: true
    },
})

// add a second port for https
switcher.listen(80, 443)