Dockerfile Syntax

Every Docker image starts from a Dockerfile. To create an image of an application or script, simply create a file called Dockerfile.

Note

It does not have an extension and begins with a capital letter D.

A Dockerfile is a simple text document where all the commands that template a container are written. The Dockerfile always starts with a base image. It contains steps to create the application or to run the script in mind.

Before we build, let's take a quick look at a few best practices on writing Dockerfiles.

Some best practices include, but are not limited to, the following:

  • Separation of concern: Ensure each Dockerfile is, as much as possible, focused on one goal. This will make it so much easier to reuse in multiple applications. ...

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