jammin

REST API Generator using Express and Mongoose

Usage no npm install needed!

<script type="module">
  import jammin from 'https://cdn.skypack.dev/jammin';
</script>

README

jammin

Installation

npm install jammin

About

Jammin is the fastest way to build REST APIs in NodeJS. It consists of:

  • A light-weight wrapper around Mongoose to perform database operations
  • An Express router to link database operations to HTTP operations

Jammin is built for Express and is fully extensible via middleware to support things like authentication, sanitization, and resource ownership.

Use API.addModel() to add an existing Mongoose model. You can attach HTTP routes to each model that will use req.params and req.query to query the database and req.body to update it.

Quickstart

var App = require('express')();
var Mongoose = require('mongoose');
var Jammin = require('jammin');
var API = new Jammin.API('mongodb://<username>:<password>@<mongodb_host>');

var PetSchema = Mongoose.Schema({
  name: String,
  age: Number
});

var Pet = Mongoose.model('Pet', PetSchema);
API.addModel('Pet', Pet);
API.Pet.get('/pets/:name');
API.Pet.post('/pets');

App.use('/v0', API.router);
App.listen(3000);
> curl -X POST $HOST/v0/pets -d '{"name": "Lucy", "age": 2}'
{"success": true}
> curl $HOST/v0/pets/Lucy
{"name": "Lucy", "age": 2}

Documentation

Database Operations

GET get() will use req.params and req.query to find an item or array of items in the database.

API.Pet.get('/pets/:name');
API.Pet.getMany('/pets')

POST post() will use req.body to create a new item or set of items in the database.

API.Pet.post('/pets');
API.Pet.postMany('/pets');

PATCH patch() will use req.params and req.query to find an item or set of items in the database, and use req.body to update those items.

API.Pet.patch('/pets/:name');
API.Pet.patchMany('/pets');

PUT put() will use req.params and req.query to find an item or set of items in the database, and use req.body to update those items, or create a new item if none exists

API.Pet.put('/pets/:name');
API.Pet.putMany('/pets');

DELETE delete() will use req.params and req.query to remove an item or set of items from the database

API.Pet.delete('/pets/:name');
API.Pet.deleteMany('/pets');

Schemas and Validation

See the documentation for Mongoose Schemas for the full set of features.

Require fields

var PetSchema = {
  name: {type: String, required: true}
}

Hide fields

var UserSchema = {
  username: String,
  password_hash: {type: String, select: false}
}

Middleware

You can use middleware to intercept database calls, alter the request, perform authentication, etc.

Change req.jammin.query to alter how Jammin selects items from the database (GET, PATCH, PUT, DELETE).

Change req.jammin.document to alter the document Jammin will insert into the database (POST, PATCH, PUT).

Change req.jammin.method to alter how Jammin interacts with the database.

Jammin also comes with prepackaged middleware to support the following Mongoose operations:

limit, sort, skip, projection, populate, select

Examples

Here are three equivalent ways to sort the results and limit how many are returned.

var J = require('jammin').middleware

// The following are all equivalent
API.Pet.getMany('/pets', J.limit(20), J.sort('+name'));
API.Pet.getMany('/pets', J({limit: 20, sort: '+name'}));
API.Pet.getMany('/pets', function(req, res, next) {
  req.jammin.limit = 20;
  req.jammin.sort = '+name';
  next();
})

The example below alters req.query to construct a complex Mongo query from user inputs.

API.Pet.getMany('/search/pets', function(req, res, next) {
  req.jammin.query = {
    name: { "$regex": new RegExp(req.query.q) }
  };
  next();
});

A more complex example achieves lazy deletion:

API.router.use('/pets', function(req, res, next) {
  if (req.method === 'DELETE') {
    req.jammin.method = 'PATCH';
    req.jammin.document = {deleted: true};
  } else if (req.method === 'GET') {
    req.jammin.query.deleted = {"$ne": true};
  } else if (req.method === 'POST' || req.method === 'PUT') {
    req.jammin.document.deleted = false;
  }
  next();
}

Or resource ownership:

var setOwnership = function(req, res, next) {
  req.jammin.document.owner = req.user._id;
  next();
}
var ownersOnly = function(req, res, next) {
  req.jammin.query.owner = {"$eq": req.user._id};
  next();
}
API.Pet.get('/pets');
API.Pet.post('/pets', setOwnership);
API.Pet.patch('/pets/:id', ownersOnly);
API.Pet.delete('/pets/:id', ownersOnly);

Manual Calls and Intercepting Results

You can manually run a Jammin query and view the results before sending them to the user. Simply call the operation you want without a path.

Jammin will automatically handle 404 and 500 errors, but will pass the results of successful operations to your callback.

app.get('/pets', J.limit(20), function(req, res) {
  API.Pet.getMany(req, res, function(pets) {
    res.json(pets);
  })
})

If you'd like to handle errors manually, you can also access the underlying model:

API.Pet.model.findOneAndUpdate(...);