For datasette/issues/1522 I wanted to use a Docker build argument in a Dockerfile that would then be deployed to Cloud Run.
I needed this to be able to control the version of Datasette that was deployed. Here's my simplified Dockerfile:
FROM python:3-alpine\n\nARG DATASETTE_REF\n# Copy to environment variable for use in CMD later\nENV VERSION_NOTE=$DATASETTE_REF\n\nRUN pip install https://github.com/simonw/datasette/archive/${DATASETTE_REF}.zip\n\n# Need to use \"shell form\" here to get variable substition:\nCMD datasette -h 0.0.0.0 -p 8080 --version-note $VERSION_NOTEI can build this on my laptop like so:
\ndocker build -t datasette-build-arg-demo . \\\n --build-arg DATASETTE_REF=c617e1769ea27e045b0f2907ef49a9a1244e577d\nThen run it like this:
\ndocker run -p 5000:8080 --rm datasette-build-arg-demo\nAnd visit http://localhost:5000/-/versions to see the version number to confirm it worked.
I wanted to deploy this to Cloud Run, using this recipe.
\nUnfortunately, the gcloud builds submit command doesn't have a mechanism for specifying --build-arg.
Instead, you need to use a YAML file and pass it with the gcloud builds submit --config cloudbuild.yml option. The YAML should look like this:
steps:\n- name: 'gcr.io/cloud-builders/docker'\n args: ['build', '-t', 'gc.io/MY-PROJECT/MY-NAME', '.', '--build-arg', 'DATASETTE_REF=c617e1769ea27e045b0f2907ef49a9a1244e577d']\n- name: 'gcr.io/cloud-builders/docker'\n args: ['push', $IMAGE]Since I want to dynamically populate my YAML file, I ended up using the following pattern in a ./deploy.sh script:
#!/bin/bash\n# https://til.simonwillison.net/cloudrun/using-build-args-with-cloud-run\n\nif [[ -z \"$DATASETTE_REF\" ]]; then\n echo \"Must provide DATASETTE_REF environment variable\" 1>&2\n exit 1\nfi\n\nNAME=\"datasette-apache-proxy-demo\"\nPROJECT=$(gcloud config get-value project)\nIMAGE=\"gcr.io/$PROJECT/$NAME\"\n\n# Need YAML so we can set --build-arg\necho \"\nsteps:\n- name: 'gcr.io/cloud-builders/docker'\n args: ['build', '-t', '$IMAGE', '.', '--build-arg', 'DATASETTE_REF=$DATASETTE_REF']\n- name: 'gcr.io/cloud-builders/docker'\n args: ['push', '$IMAGE']\n\" > /tmp/cloudbuild.yml\n\ngcloud builds submit --config /tmp/cloudbuild.yml\n\nrm /tmp/cloudbuild.yml\n\ngcloud run deploy $NAME \\\n --allow-unauthenticated \\\n --platform=managed \\\n --image $IMAGE \\\n --port 80