microservice-skeleton

Introduction

This is a simple NodeJS module for creating creating simple API-based microservices. It is very easy to follow the MVC design pattern, and because of this, designing your microservice using a MVC pattern is recommended. It is based on Express and uses controllers for managing the URL routes. It is configured to deal with JSON requests, using bodyParser.

Hooks

It uses hooks for inserting functionality. Each hook allows to receive a parameter from the skeleton. The list of available hooks is listed below:

• express: Loaded at the beginning, right after setting up the Express instance. The accessible parameter is the Express instance (app), which you can customize as preferred.
• controllers: It is loaded during controller loading, to allow creating custom controllers. The parameter is the controller directory register function, to which you would pass the full path to directory where controllers are located.

Controllers

The controllers structure is very simple, and work via keys that point to an Express router function. For instance, if the controller's file name is login.js and it implements the get function, it would be accessible with a GET request to /login.

For instance, take a look at the liveness.js file, located at lib/controllers/liveness.js:

'use strict';
module.exports = {
  get: (req, res, next) => {
    res.json({
      hello: 'world'
    });
  }
};

Allowed methods

Since this module is meant for creating API-based microservices, it only supports a few types of HTTP requests. Supposing the microservice is named login.js, you would be able to define the following HTTP methods in your controller file:

• index: GET request to /.
• get: GET request to /login.
• post: POST request to /login.
• put: PUT request to /login.
• show: GET request to /login/:id.
• edit: POST request to /login/:id.
• delete: DELETE request to /login/:id.

### Liveness and readiness

This module is meant for creating simple microservices that can be deployed with Kubernetes. Because of this, there are already two predefined controllers, liveness and readiness, accessible at /liveness and /readiness respectively:

• /liveness will always show a simple {"hello":"world"} response, used to checking whether the microservice is running or not (if it is not, the page would not be accessible).
• /readiness will show a simple {"ready":STATUS} response, where STATUS is either true or false. The default value is false which you have to change in your microservice as following, in the express hook:

app.set('ready', true)

License

Copyright 2016 Marcos Bjørkelund

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.