As the name implies, this package generates a .dockerignore
for you based on .gitignore
rules
found in your source tree.
Why generate this file, you ask? Because there are a number of differences between
.dockerignore
and .gitignore
rule processing which can make it non-trivial to make
your Docker file tree match your local git tree.
Generating your .dockerignore
file based on your configured .gitignore
rules means you only have
to think about which files should not be distributed with your project only once. This also can
promote reproducible builds by ensuring that the only files your Docker context has access to are
those files that are tracked by your git repository.
The following differences between .dockerignore
vs .gitignore
processing are handled by this tool:
behavior | .gitignore | .dockerignore |
---|---|---|
plain patterns without slashes or wildcards | ⏬️ match recursively | ⬆️ match top-level only |
separate per-directory ignore files | ✅ allowed | ❌ not allowed |
local .git/info/exclude file | ✅ included | - |
global core.excludesFile file | ✅ included | - |
The code's handling of these behavioral differences is tested using actual git and Docker calls, followed by validation that the resultant git source trees are equal to the Docker build contexts.
References:
- https://git-scm.com/docs/gitignore
- https://docs.docker.com/engine/reference/builder/#dockerignore-file
pip install generate-dockerignore-from-gitignore
usage: generate-dockerignore [-h] [-C DOCKER_ROOT] [-v] [-o OUTPUT] [PATH ...]
.dockerignore file generator based on .gitignore file(s)
positional arguments:
PATH gitignore file(s), or directories under git source control (which will be
searched for **/.gitignore).
options:
-h, --help show this help message and exit
-C DOCKER_ROOT, --docker-root DOCKER_ROOT
Docker context directory to chdir into before continuing
-v, --verbose Output per-file logging to stderr
-o OUTPUT, --output OUTPUT
File path for generated .dockerignore rule output, or - for stdout
(default: .dockerignore)