Node.js Producer-Consumer Challenge

The assignment is to build a simple Producer/Consumer system. In this system the Generator (Producer) will send a series of random arithmetic expressions, while the Evaluator (Consumer) will accept these expressions, compute the result and then report the solution to the Generator (Producer).

Setup & Configuration

1. Run npm install
2. Optionally edit config.js to define a custom host, port, and other basic options

Running unit tests

1. Run npm test
2. Watch the magic happen

Starting the Consumer

The Consumer listens for requests containing an expression POST parameter, parses the mathematical expression, evaluates it, and responds to the requester with the answer (or error). All incoming requests to the Consumer are logged to the console, as are the answers for each expression.

1. Run npm run consumer
2. Optionally make a POST request to http://localhost:7000/ using Content-Type application/x-www-form-urlencoded or application/json with an expression payload (e.g. 2+3=)

Starting a Producer

An instance of the Producer will form an expression consisting of 2 random integers and a random mathematical operator (+, -, *, /) at a rate of once per second (unless otherwise specified via an environment variable or by altering the config.js file). After constructing each random expression, it will attempt to send it to the Consumer via an HTTP POST request to be evaluated and receive an answer. Each generated expression is logged to the console, as are the answers received from the Consumer. You may run multiple instances of the Producer at a time.

1. Run npm run producer
2. Repeat for as many Producer instances you would like to run simultaneously

Screenshot

UML Activity Diagram

UML Sequence Diagram

Requirements

Engines

• Node.js >= 0.10.42
• NPM >= 1.4.29

Dependencies

• Async 1.5.2
• body-parser 1.15.0
• connect 3.4.1
• log4js 0.6.31
• request 2.69.0

Dev Dependencies

• Mocha 2.4.5
• Sinon-Chai 2.8.0