This repository creates 2 RESTful web services using nodejs to demonsrate contract testing using pactjs. The "accounts" service acts as the consumer and the "users" service is a producer.

The "account" service is called with necessary parameters which in turns calls the "users" service to fetch the resources from the database which in this case is a cloud hosted MongoDB instance.

How to use the repo?

• clone the repo

• create a mongodb sandbox on mLab and update the connection string in config.json. It should look like mongodb://:@ds123963.mlab.com:23963/mongo-sandbox

  or

• run a docker instance of mongodb using the following steps

  • docker pull mongo
  • docker run --name <name of db> --restart=always -d -p 27017:27017 mongo mongod now update the connection string in config.json. It should be mongodb://localhost:27017

• execute the command - npm install (run npm --version to verify whether npm is installed)

• execute the command - npm start

The server now runs at http://localhost:3000

How to create a new account?

• Send a POST request with the JSON object in the body e.g. url - http://localhost:3000/accounts/ body - {"id": "1000", "name": "lorem epsum", "email": "lorem.epsum@dolor.com"}

How to get all accounts from database?

• Send a GET request with no parameter e.g. http://localhost:3000/accounts/

How to get an account by its ID?

• Send a GET request with id as the parameter e.g. http://localhost:3000/accounts/2

Detailed Explanation

We are using the following npm modules to develop the web service

• express - the defacto framework to develop nodejs based web application
• mongoose - the nodejs based ORM to manage interaction with MongoDB
• body-parser - a middleware to parse our data sent through http requests
• requests - to make http requests such as GET, POST, DELETE etc to another webservice
• connect-timeout - defines the timeout for an http call

app.js - used just to configure the app. It defines the javascript program to be executed when an endpoint is called e.g. app.js contains the following line

var UserController = require('./user/UserController');
app.use('/users', UserController);

server.js - defines the port express server listening on

db.js - defines the mongodb instance the mongoose ORM connects to

config.js - reads the config.json for the configuration parameters

config.json - defines the default(development) configuration values and the environment specific configurations

user/User.js - defines the schema for User document. This helps mongoose exchange the data between the service and mongodb.

user/UserController.js - The controller service controls the flow of data into and from database. When we make a http GET request to user service to fetch all user information from MongoDB, the request is routed through router.get(...).