dockerignore speeds up builds

Many of Caliban’s commands begin their work by triggering a docker build command; this command has a side effect of bundling up the entire directory where you run the command into a “build context”, which is zipped up and sent off to the Docker build process on your machine.

In a directory containing machine learning code, it’s not unusual that you might also have subdirectories that contain, for example:

  • large datasets that you’ve cached locally

  • tensorboard output from local runs

  • metrics

If you don’t want to include any of these things in the Docker container that caliban builds for you, you can significantly speed up your builds by creating a file called .dockerignore in the directory of your project.

Here’s an example .dockerignore file, with comments explaining each line:

# ignore the git repository info and the pip installation cache

# this is huge - ignore the virtualenv we've created inside the folder!

# tests don't belong inside the repo.

# no need to package info about the packaged-up code in egg form.

# These files are here for local development, but have nothing
# to do with the code itself, and don't belong on the docker image.

As a starting point, you might take your project’s .gitignore file, copy everything other to .dockerignore and then delete any entries that you actually DO need inside your Docker container. An example might be some data you don’t control with git, but that you do want to include in the container using Caliban’s -d flag.