how to use docker in development

Question

I am new to docker and I have done some ground work on docker like how to build a image, how to create a container, what is dockerfile.yml, docker-compose.yml file does etc. I have done my practice in my local machine. I am having following questions when it is coming to real time development using docker.

1) Does each developer in a team has to do development on docker and create images in their local machine and push it to docker registry ? or developers work without docker and one person will be creating final image from the committed code?

2) For each release, do we maintain the container or an image for that release?

3) what is the best practice to maintain the database means do we incorporate the database in image and build the container or we include only application related things and build image and container, and this container will communicate to database which is in outside container or physical database server ?

Thanks in advance.

Answer 1

Questions like these generally do not have a definitive answer. It depends heavily on your company, your team, the tooling that is being used, the software stack, etc. The best thing to do would be to lean on the senior development resources and senior technical leadership in your organization to help shape the answers to questions like these.

Take the following answers with a silo of salt as there is no way to answer these kinds of questions definitively.

1) Depends on what is most convenient for the developers and what language you are using. Some developers find an all container workflow to be convenient, some developers find they can iterate faster with their existing IDE/CLI workflow and test against running container images last.

In most cases you will want to let CI/CD tooling take care of the builds that are intended for production.

2) Yes. You can use container tagging for this purpose.

3) Running databases in containers is possible, but unless your team is experienced with containers and container orchestration I would leave the databases on traditional bare-metal or VMs.

Containers are a fancy wrapper around a single linux process. Generally the rule of thumb is one container for one process. You should not be combining multiple things in a single container. (This story gets slightly more complicated when you go to something like Red Hat OpenShift or Kubernetes as the discussion revolves around how many containers per pod).