Middle Earth

Middleware manager for Express.js

Why...?

Core objective is to keep configurations for different enviroments/use cases in one spot vs. spreading them out based on where they need to be loaded.

Install

npm install middle-earth

Usage

Examples below are basic. But should provide you with an idea of what you can do.

---

var express = require('express');
var MiddleEarth = require('middle-earth');

var app = express();

Appending and/or prepending.

app
  .middlewares([
    {name: 'body-parser', cb: bodyParser()},
    {name: 'method-override', cb: methodOverride()}
  ]);

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app
    .middlewares()
    .prepend([
      {name: 'basicAuth', cb: express.basicAuth("user", "strong")}
    ])
    .append([
      {name: 'something-else', cb: somethingElse()},
      {name: 'and-another', cb: andAnother()}
    ]);
}

app.middlewares().finish();

Equivalent to:

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app.use(express.basicAuth("user", "strong"));
}

app.use(bodyParser());
app.use(methodOverride());

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app.use(somethingElse());
  app.use(andAnother());
}

---

You can also insert a middleware before or after another.

app
  .middlewares([
    {name: 'body-parser', cb: bodyParser()},
    {name: 'method-override', cb: methodOverride()}
  ]);

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app
    .middlewares()
    .before('body-parser', {name: 'basicAuth', cb: express.basicAuth("user", "strong")});
    .after('body-parser', {name: 'other', cb: other()});
}

app.middlewares().finish();

Equivalent to:

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app.use(express.basicAuth("user", "strong"));
}

app.use(bodyParser());
app.use(methodOverride());

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app.use(other());
}

---

Pathed middlewares

app
  .middlewares([
    {name: 'body-parser', cb: bodyParser()},
    {name: 'method-override', cb: methodOverride()},
    {name: 'static', cb: express.static(__dirname+'/../public')}
  ])

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app
    .middlewares()
    .prepend([
      {name: "basic-auth", cb: express.basicAuth("user", "strong"), path: "/admin"}
    ])
    .append([
      {name: 'other', cb: other()}
    ]);
}

app.middlewares().finish();

Equivalent to:

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app.use("/admin", express.basicAuth("user", "strong"));
}

app.use(bodyParser());
app.use(methodOverride());
app.use(express.static(__dirname+'/../public'));

if (['production', 'staging'].indexOf(process.env.NODE_ENV) >= 0) {
  app.use(other());
}

---

Execute a function at a specific point. Primary use would be to allow routes to be mapped at a particular spot.

var route = express.Router();
route.get("/posts", function(req, res, next) {
  res.send(200);
});

app
  .middlewares([
    {name: 'compress', cb: compress()},
    {name: 'logger', cb: Log.logger('dev')},
    {name: 'body-parser', cb: bodyParser()},
    {name: 'method-override', cb: methodOverride()},
    {name: 'cookie-parser', cb: cookieParser('secret')},
    {name: 'session', cb: session({secret: 'secret', key: 'sid', cookie: {secure: true}})},
    {name: 'csrf', cb: Csrf.csrf()},
    {name: 'csrf-local-token', cb: Csrf.localToken()},
    {name: 'static', cb: express.static(__dirname+'/../public')}
  ]);

app
  .middlewares()
  .before('static', {name: 'routes', fn: function() {
    app.use(route);
  }});

app.middlewares().finish();

Equivalent to:

app.use(compress());
app.use(Log.logger('dev'));
app.use(bodyParser());
app.use(methodOverride());
app.use(cookieParser('secret'));
app.use(session({secret: 'secret', key: 'sid', cookie: {secure: true}}));
app.use(Csrf.csrf());
app.use(Csrf.localToken());
app.use(route);
app.use(express.static(__dirname+'/../public'));

---

Removing a middleware from the queue.

app
  .middlewares([
    {name: 'body-parser', cb: bodyParser()},
    {name: 'method-override', cb: methodOverride()},
    {name: 'static', cb: express.static(__dirname+'/../public')},
    {name: 'logger', cb: logger()}
  ])

if ('test' === process.env.NODE_ENV) {
  app
    .middlewares()
    .remove('logger');
}

app.middlewares().finish();

Equivalent to:

app.use(bodyParser());
app.use(methodOverride());
app.use(express.static(__dirname+'/../public'));

if ('test' != process.env.NODE_ENV) {
  app.use(logger());
}

---

Ovewrite an existing middleware in the queue.

app
  .middlewares([
    {name: 'overwrite-me', cb: fn1()},
    {name: 'no-touchy', cb: fn2()}
  ]);

if ('test' === process.env.NODE_ENV) {
  app
    .middelwares()
    .overwrite('overwrite-me', {name: 'diff-name', cb: fn3()});
}

app.middelwares().finish();

Equivalent to:

if ('test' === process.env.NODE_ENV) {
  app.use(fn3());
} else {
  app.use(fn1());
}

app.use(fn2());

You may also just pass it a middlware/function.

  app
    .middelwares()
    .overwrite('overwrite-me', function(req, res, next) {
      next();
    });

Note, make sure you don't confuse your "middlewares" with the "function" executables you can add to the queue.

Important

This does not alter middlewares already applied (use'd) on the app.

You can use it in conjuction with the normal app.use(), but middlewares will be applied when you call #finish() and the order will be set accordingly to that invocation point.

Test

npm test

License

MIT