feat: ability to pass docker build options via env variable TUTOR_DOCKER_BUILD_ARGS

feat: use --docker-arg flag instead of env variable to pass docker build options

chore: remove unused import

chore: added changelog

feat: added shorthand -d for --docker-arg

fix: typo

CHANGELOG.md

@@ -8,6 +8,7 @@ Note: Breaking changes between versions are indicated by "💥".
 
 - [Bugfix] Fix 500 error during user registration.
 - [Bugfix] Fix Mongodb compatibility version upgrade when upgrading from Koa to Lilac.
+- [Feature] Ability to pass [docker build options](https://docs.docker.com/engine/reference/commandline/build/#options) via ``--docker-arg`` option in ``tutor images build`` command.
 
 ## v12.1.2 (2021-09-18)
 

docs/configuration.rst

@@ -372,3 +372,17 @@ By default, Tutor runs the `overhangio/openedx <https://hub.docker.com/r/overhan
 (See the relevant :ref:`configuration parameters <docker_images>`.)
 
 The customised Docker image tag value will then be used by Tutor to run the platform, for instance when running ``tutor local quickstart``.
+
+
+Passing custom docker build options
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+You can set a limited set of Docker build options via ``tutor images build`` command. In some situations it might be necessary to tweak the docker build command, ex- setting up build caching using buildkit.
+In these situations, you can set ``--docker-arg`` flag in the ``tutor images build`` command. You can set any `supported options <https://docs.docker.com/engine/reference/commandline/build/#options>`_ in the docker build command, For example::
+
+    tutor images build openedx \
+        --build-arg BUILDKIT_INLINE_CACHE=1 \
+        --docker-arg="--cache-from" \
+        --docker-arg="docker.io/myusername/openedx:mytag"
+
+This will result in passing the ``--cache-from`` option with the value ``docker.io/myusername/openedx:mytag`` to the docker build command.

tutor/commands/images.py

@@ -54,6 +54,13 @@ def images_command() -> None:
     "--target",
     help="Set the target build stage to build.",
 )
+@click.option(
+    "-d",
+    "--docker-arg",
+    "docker_args",
+    multiple=True,
+    help="Set extra options for docker build command.",
+)
 @click.pass_obj
 def build(
     context: Context,
@@ -62,6 +69,7 @@ def build(
     build_args: List[str],
     add_hosts: List[str],
     target: str,
+    docker_args: List[str],
 ) -> None:
     config = tutor_config.load(context.root)
     command_args = []
@@ -73,6 +81,8 @@ def build(
         command_args += ["--add-host", add_host]
     if target:
         command_args += ["--target", target]
+    if docker_args:
+        command_args += docker_args
     for image in image_names:
         build_image(context.root, config, image, *command_args)