Docker for Rails Developers

How Do We Run Our Rails App?

Unfortunately, we can’t start a Rails server with just the ruby:2.6 image—Rails has a few more requirements. For example, we’re going to need a JavaScript interpreter (like Node.js) to help with the asset pipeline, plus we’ll need to install our gem dependencies. How do we run a Rails server in a container while making sure that these requirements are satisfied?

There are a few approaches we could take. We could do what we did in the previous chapter: run bash inside a container based on the ruby:2.6 image, and install what we need from there. However, running the commands manually is not easily repeatable. We want a reliable, repeatable way of spinning up Rails servers left, right, and center. Having to run various ...