lab-restful-flask

This repo demonstrates how to create a simple RESTful service using Python Flask. The resource model has no persistence to keep the application simple. It's purpose is to show the correct API and return codes that should be used for a REST API.

Prerequisite Installation using Vagrant

The easiest way to use this lab is with Vagrant and VirtualBox. if you don't have this software the first step is down download and install it.

Download VirtualBox

Download Vagrant

Clone the project to your development folder and create your Vagrant vm

    git clone https://github.com/nyu-devops/lab-restful-flask.git
    cd lab-restful-flask
    vagrant up

Once the VM is up you can use it with:

    vagrant ssh
    cd /vagrant
    python run.py

You should now be able to see the service running in your browser by going to http://localhost:5000. You will see a message about the service which looks something like this:

{
    name: "Pet Demo REST API Service",
    url: "http://localhost:5000/pets",
    version: "1.0"
}

When you are done, you can use Ctrl+C within the VM to stop the server.

Alternative starting of the service

For running the service during development and debugging, you can also run the server using the flask command with:

    flask run -h 0.0.0.0

Note that we need to bind the host IP address with -h 0.0.0.0 so that the forwarded ports work correctly in Vagrant. If you were running this locally on your own computer you would not need this extra parameter.

Finally you can use the honcho command to start gunicorn to run the servce with:

    honcho start

Honcho uses the Procfile to determine how to run the service. This file uses Gunicorn which is how you would start the server in production.

Testing

Run the tests suite with:

    nosetests

You should see all of the tests passing with a code coverage report at the end. this is controlled by the setup.cfg file in the repo.

Shutdown

When you are done, you can use the exit command to get out of the virtual machine just as if it were a remote server and shut down the vm with the following:

    exit
    vagrant halt

If the VM is no longer needed you can remove it with from your computer to free up disk space with:

    vagrant destroy

This repo is part of the NYU masters class: CSCI-GA.2820-001 DevOps and Agile Methodologies created by John Rofrano.