easy-express-controllers

This project adds traditional MVC controller support to Express with JavaScript classes, and ES-next decorators. This allows you to set up your Express routes with simpler code, and significantly less boilerplate.

Special thanks to Oleksandr Hulyi https://github.com/pamidur for his work in adding default Web API-style routes, as well as default route paths.

For example, if this class was in product.js

import {httpGet, httpPost} from 'easy-express-controllers';
 
export default class Product {
    @httpGet
    getProduct({id}){
        this.send({name: 'Some Product', id: id});
    }
 
    @httpPost
    save({id, name, price}){
        this.send({saved: true});
    }
 
    //You can also override the route
    //This will use the default route, meaning GET product/
    //If I'd written @httpGet('all') this action would be
    //available at GET product/all
    @httpGet('') 
    allProducts(){
        this.send({products: [{id: 1, name: 'Product 1'}]})
    }
}

you'd now be able to

fetch('/product/getProduct?id=12')
    .then(resp => resp.json)
    .then(resp => console.log(resp));

and log {"name":"Some Product","id":"12"}. Or

fetch('/product/save', 
    {
        method: 'post',
        body: JSON.stringify({id: 12, name: 'new name', price: 9.99})
    }
).then(resp => resp.json)
 .then(resp => console.log(resp));

which will log {"saved":true}. Or

fetch('/product/')
    .then(resp => resp.json)
    .then(resp => console.log(resp));

which will log {"products":[{"id":1,"name":"Product 1"}]}

---

NOTE THE DESCTUTURING IN THE CLASS METHODS

To avoid difficulties, remember that you have to do

export default class Product {
    @httpGet
    getProduct({id}){
        this.send({name: 'Some Product', id: id});
    }
}

as opposed to something like

export default class Product {
    @httpGet
    getProduct(id){  // <------- WRONG - won't work!!!
        this.send({name: 'Some Product', id: id});
    }
}

which many MVC frameworks support.

It's not only viciously difficult to parse a function's definition to sniff out variable names (especially now that default values and destructuring are allowed) it's effecively impossible since transpilers can, and do change the name of function parameters.

So your methods will be passed a single object, containing properties for every parameter sent over the wire. You can destructure whatever you need in the parameter list, or of course just deal with the object itself

export default class Product {
    @httpGet
    getProduct(params){
        let id = params.id; // <----- fine if you prefer
        this.send({name: 'Some Product', id: id});
    }
}

---

Paths are also respected, so if this class is inside an admin directory

import {httpGet, httpPost} from 'easy-express-controllers';
 
export default class Settings {
    //get is the default, so this decorator could have been omitted  
    @httpGet 
    getSettings({id}){
        this.send({membershipLevel: 'Pro', id: id});
    }
 
    @httpPost
    save({id, newMembershipLevel}){
        this.send({saved: true});
    }
}

then

fetch('/admin/settings/getSettings?id=12')
    .then(resp => resp.json)
    .then(resp => console.log(resp));

will log {"membershipLevel":"Pro","id":"12"}, while

fetch('/admin/settings/save', 
    {
        method: 'post',
        body: JSON.stringify({id: 12, newMembershipLevel: 'Gold'})
    }
).then(resp => resp.json)
 .then(resp => console.log(resp));

will log {"saved":true}

You can also create a more traditional REST api, like this

import {httpGet, httpPost} from 'easy-express-controllers';
 
export default class RestProduct {
    get({id}){
        this.send({name: 'Some Product', id: id});
    }
 
    post({id, name, price}){
        this.send({updated: true});
    }
 
    put({id, name, price}){
        this.send({inserted: true});
    }
 
    delete({id}){
        this.send({deleted: true})
    }
}

so this,

fetch('/restproduct/?id=12')
    .then(resp => resp.json)
    .then(resp => console.log(resp));
 
fetch(
    '/restproduct', 
    { 
        method: 'post',
        body: JSON.stringify({id: 12, name: 'new val', price: 15}) 
    }
)
.then(resp => resp.json)
.then(resp => console.log(resp));
 
fetch('/restproduct', 
    { 
        method: 'put', 
        body: JSON.stringify({id: 12, name: 'new product', price: 9.99}) 
    }
)
.then(resp => resp.json)
.then(resp => console.log(resp));
 
fetch('/restproduct', 
    { 
        method: 'delete', 
        body: JSON.stringify({id: 12}) 
    }
)
.then(resp => resp.json)
.then(resp => console.log(resp));

will all work as expected.

---

Wiring these controllers up is simple.

const {createAllControllers} = require('easy-express-controllers');
createAllControllers(app, {__dirname: './node-dest', controllerPath: 'myControllers'});

this tells easy-express-controllers that your controller classes are in ./node-dest/myControllers. If you name your controllers directory controllers then you can leave that option off, since it's the default.

createAllControllers(app, {__dirname: './node-dest'});

and if your (transpiled) controllers directory is at the top level, relative to where this code is being run, you can just do

createAllControllers(app);

And of course everything is configurable. See below for the full docs. If you've already been using this library, note that all of the old configuration will continue to work now and going forward, even though I've simplified a few things.

Full Docs

Class methods and routes

Each method found on your class's prototype through Object.getOwnPropertyNames will become a route for the path /{your controller path}/{method name}. If you have a class method that you want to never be routed to, you can either define it with a symbol, so Object.getOwnPropertyNames misses it, or just add the @nonRoutable decorator.

These routes are added through Express 4's router, and the call to app.use is passed the controller class's path. So if your controller was located at books/book.js, and had a method details, then the path would be books/book/details. The base path of the contorller can be overridden with the @controller decorator, which accepts an object literal; the path property therein overrides this value. For example, if this controller was located under the controllers directory at publisher/publisherDetails.js

@controller({ path: 'publisher' })
class publisherDetails {
    details(){
        this.send({ received: true });
    }
}

then the path to the details method would be /publisher/details, as opposed to publisher/publisherDetails/details if this decorator were absent.

Overriding route paths

If you want to override the path for a method, just pass the route to whichever verb decorator you're using. For example

class Thing {
    @httpGet('foo')
    bar(){
 
    }
}

will now route to thing/foo instead of thing/bar.

You can also use the route decorator if you'd like; the following will have the same effect.

class Thing {
    @route('foo')
    bar(){
 
    }
}

If you'd like to set the complete path for a controller action, overriding even the base controller path, just use a leading slash. For example

@httpPost('/some-global-path/:userId')
about({ userId }){
}

now /some-global-path/:userId will trigger the method above, regardless of what controller it sits in, or the path thereto.

Path verbs

Methods default to GET. To override this, you can add one or more decorators of @httpPost, @httpGet, @httpPut and @httpDelete, or add multiple verbs at one time through @acceptVerbs, which accepts an array, for example @acceptVerbs(['put', 'delete']).

Setting a class-level default path verb

If you want your class methods to default to something other than GET, use the defaultVerb property on the @controller decorator.

@controller({ defaultVerb: 'post' })
export default class Book {
    details(){
        this.send({ received: true });
    }
    @httpPost
    foo({ x }){
        this.send({ x });
    }
    @httpGet
    foo2({ x }){
        this.send({ x });
    }
}

Handling Routes

Inside the controller method the following methods from the response object will be directly available through this: send, sendFile, json, jsonp. The original request and response objects are also available through this.request and this.response respectively.

Using parameters in route methods

Methods are passed an object with all values from request.params, request.query, and request.body in that order of precedence: a value from request.params overrides a matching value from request.body. You can either accept the object as is, or destructure what you need right in the method definition, as the examples above do.

NOTE: to ensure parameter parsing works make sure you have your middleware setup appropriately:

var bodyParser = require('body-parser');
 
app.use(bodyParser.json());       // to support JSON-encoded bodies
app.use(bodyParser.urlencoded({     // to support URL-encoded bodies
    extended: true
}));

Turning an ES6 class into express paths

const {createController} = require('easy-express-controllers');
createController(app, 'person');

The code above will require person.js from under a root-level controllers directory.

This code gets to the root controllers directory in part with path.dirname('.') which is equivalent to process.cwd(). This can easily be wrong depending on which directory your app was launched from. If you can't, or don't want to rely on this being correct, you can pass in a third argument of an object literal. If the object has a __dirname property, then that will be used in place of path.dirname('.'). The object literal can also have a controllerPath property which overrides the default value of just 'controllers'; it should be the relative path from the root of your application to your controllers directory, or a relative path from the overridden __dirname value you passed in, described above, to your controllers directory.

For example, if for whatever reason you're running createController from a module one level beneath the root, and pointing to a root level directory called controllers2 then this code will work

createController(app, 'books/foo', { __dirname: __dirname, controllerPath: '../controllers2' });

Or of course this would also work under the same circumstances, assuming process.cwd could be used.

createController(app, 'books/foo', { controllerPath: 'controllers2' });

To have easy-express-controllers walk your directory tree and create all controllers for you, you can also call createAllControllers

const {createAllControllers} = require('easy-express-controllers');
createAllControllers(app);

This sniffs out all js files at any level under your controllers directory, and calls createController for you. By default, only .js files will be processed; if your es6 transpiled files are named with a .es6 extension (or something else that's not .js) then you'll be all set. If your ES6 files have a .js extension, then you can pass a config object as your second argumentwith a fileTest property specifying which files to process, like so

createAllControllers(app, { fileTest: f => !/-es6\.js$/i.test(f) });

which of course will skip processing for all files that end in -es6.js.

This config object also accepts the same __dirname and controllerPath properties, discussed above.

Setting up Babel 6

Use the babel-plugin-transform-decorators-legacy plugin to handle decorators. If using Gulp, your call may look like this

.pipe(babel({ presets: ['babel-preset-es2015'], plugins: ['transform-decorators-legacy'] }))