Travis CI - Docker Image - We need `latest` and `stable` images

[franck-boullier]

Context:

• We are relying on a docker image to deploy the frontend.
• When deploying the services, we are using the latest of these docker image regardless of the environment we are in.

The problem:

• If we make some change to that docker image that are breaking something, these changes will be introduced in the latest version of the docker image.
• If we have to redeploy PROD or DEMO, these will use the latest image too,

Solution:

We need:

• another docker image stable that will have been thouroughly tested.
• a procedure to update that stable image
• edit the deployment script so that the Docker image that are used for deployments are:
  • latest for the DEV environment
  • stable for the DEMO and PROD environment.

[kaihendry]

This current idea is that dev runs latest and production/demo runs tagged releases.

For example production currently runs uneet/frontend:c972242 right now. I wrote https://version.dev.unee-t.com/ to track this.

https://hub.docker.com/repository/docker/uneet/frontend

We can introduce {stable,latest} labels but that would basically obfuscate what the current version is.