This application should be deployed automatically on and by the infrastructure described in another project, based on Docker, Mesos/Marathon and GitLab CI. Most of the content is in the documentation of the infrastructure project, so make sure to check it.

What it does

This application basically just counts clicks on a button and stores the number of clicks in redis. It exposes 3 endpoints :

• GET on rest/click: get the current click counter value from redis
• PUT on rest/click: increment and get the click counter value; this is what is called when the button is pressed
• GET on rest/healtcheck: provides the state (ok / ko) of the redis connection

In addition to that, a basic HTML page is also returned when GET-ting /, containing the current counter value and the previously presented button.

The redis host it connects to is provided by the environment variable REDIS_HOST, with no default value in case it is not provided so don't forget to set it !

Workflow

There are currently 4 steps:

• build
• cleanup
• (test)
• staging
• production

The first steps are run on each commit, while deployments to staging or production are ruled like this:

• Every tag is deployed to staging
• Every commit/merge in master is deployed to production

This way, it lets a lot of "liberty" to the developers; just commit on the branch when you want to have your work built and tested, tag to release to staging, and submit a Merge Request on master for a production release.

Development and manual testing

While developing the application, you can:

• run make build to build the Docker image horgix/click-count with the tag dev
• run make dev to:
  • run a local instance of redis
  • run a local instance of the application built by the previous step, linked to the redis, and accesible at localhost:8080