deployments-rolling

Node.js API App Demo

This project builds a Node.js-based API app inside a VM. It is meant as a demonstration of application deployments (in this case, a Node.js-based app) using Ansible.

Building the VM

1. Download and install VirtualBox.
2. Download and install Vagrant.
3. [Mac/Linux only] Install Ansible.
4. Run ansible-galaxy install -r requirements.yml in this directory to get the required Ansible roles.
5. Run vagrant up to build the VM and deploy the version of the app specified in playbooks/vars.yml.

Once the VM is built, you can test the API by running the following command (copy and paste verbatim, without the leading $), which requests the /hello/:name endpoint on each server:

$ for i in {2..5}; \
    do curl -w "\n" "http://192.168.56.$i:8080/hello/john"; \
  done

If the above command outputs "hello john" on four lines, everything worked correctly!

Deploying application updates

The first 'production' release of this demo app is version 1.0.0, which contains one simple endpoint for /hello/:name and an integration test to make sure it's working correctly. Subsequent releases can be deployed by incrementing the app_version in playbooks/vars.yml, then running the Ansible provisioner again with vagrant provision.

Some notable releases you could test:

• 2.0.0: The first stable release, passing all tests.
• 2.0.1: A code change was made which broke one of the tests.
• 2.0.2: The code was fixed, and all tests pass again.

About the Author

This project was created by Jeff Geerling as an example for Ansible for DevOps.