connect-version

Multiple Versioned Applications/APIs with Connect

Getting Started

$ npm install connect-version

API

var connectVersion = require('connect-version');
 
app.use(connectVersion(options));

The connectVersion object is a factory function to create middleware enabling multiple versions of an application to be hosted by a single connect server. The options parameter provides configuration for the factory. It provides a dictionary of supported version numbers and the corresponding middlewares/routers/sub-applications to use when the version is requested.

By default, connect-version uses Content-Type negotiation to determine the correct version number to use for an incoming request.

Example

Varying Application/API version by Content-Type

This example demonstrates using content type negotiation to return a different response body based on what version the client whats to accept. The server lists it's supported versions via the options parameter and will use semantic versioning to find an appropriate match for the client's request.

// server.js
var express = require('express');
var connectVersion = require('connect-version');
 
var app = express();
 
var options = {
  versions: {
    '2.0.0-beta.1': require('./routes/2.0.0-beta.1'),
    '1.2.3': require('./routes/1.2.3')
  },
  match: 'Content-Type' // this is the default matcher
};
 
app.use(connectVersion(options));
 

// routes/1.2.3/index.js
var express = require('express');
var app = module.exports = express();
 
// normal routes defintions
app.get('/', function(req, res) {
  res.send('Hello from version 1.2.3!');
});
 

// routes/2.0.0-beta.1/index.js
var express = require('express');
var app = module.exports = express();
 
// middleware that only applies to this version of the API
app.use(function(req, res, next) {
  console.log('Woah, this user is on the bleeding edge!');
  next();
});
 
// normal routes defintions
app.get('/', function(req, res) {
  res.send('Hello from version 2.0.0-beta.1!');
});
 

Example Request:

GET / HTTP/1.1
Host: example.com
Accept: application/vnd.com.myservice+text;version=1.2.x

Example Response:

HTTP/1.1 200 OK
Content-Type: text/html; charset=utf-8

Hello from version 1.2.3!