Parametise python builder version in Kapitan Dockerfile

.github/workflows/test-build-publish.yml

@@ -82,7 +82,7 @@ jobs:
           report-title: 'Kapitan tests'
 
   build:
-    name: build ${{ matrix.platform }} image
+    name: build ${{ matrix.platform }} image using python ${{ matrix.python-version }}
     if: success() || failure()   # Continue running if other jobs fail
     runs-on: ubuntu-latest
     strategy:
@@ -91,6 +91,11 @@ jobs:
         platform:
           - linux/amd64
           - linux/arm64
+        python-version:
+          - '3.10'
+          - '3.11'
+          - '3.12'
+          - '3.13'
     steps:
       - name: Checkout kapitan recursively
         uses: actions/checkout@v4
@@ -115,6 +120,8 @@ jobs:
           tags: local-test-${{ matrix.platform }}
           cache-from: type=gha,scope=$GITHUB_REF_NAME-${{ matrix.platform }}
           cache-to: type=gha,mode=max,scope=$GITHUB_REF_NAME-${{ matrix.platform }}
+          build-args: |
+            - PYTHON_VERSION=${{ matrix.python-version }}
 
       - name: Test Kapitan for ${{ matrix.platform }}
         run: |
@@ -133,6 +140,15 @@ jobs:
         platform:
           - linux/amd64
           - linux/arm64
+        python-version:
+          - '3.10'
+          - '3.11'
+          - '3.12'
+          - '3.13'
+    outputs:
+      python-version: ${{ matrix.python-version }}
+      platform: ${{ matrix.platform }}
+
     steps:
       - name: Checkout kapitan recursively
         uses: actions/checkout@v4
@@ -163,7 +179,7 @@ jobs:
         with:
           # list of Docker images to use as base name for tags
           images: |
-            name=${{ vars.DOCKERHUB_REPOSITORY }}/kapitan
+            name=${{ matrix.python-version }} == '3.11' && ${{ vars.DOCKERHUB_REPOSITORY }}/kapitan || ${{ vars.DOCKERHUB_REPOSITORY }}/kapitan-py${{ matrix.python-version }}
           # generate Docker tags based on the following events/attributes
           tags: |
             type=ref,event=branch
@@ -187,6 +203,8 @@ jobs:
           labels: ${{steps.meta.outputs.labels}}
           cache-from: type=gha,scope=$GITHUB_REF_NAME-${{ matrix.platform }}
           cache-to: type=gha,mode=max,scope=$GITHUB_REF_NAME-${{ matrix.platform }}
+          build-args: |
+            - PYTHON_VERSION=${{ matrix.python-version }}
 
   build-multi-architecture:
     name: combine platform images
@@ -219,7 +237,7 @@ jobs:
         with:
           # list of Docker images to use as base name for tags
           images: |
-            name=${{ vars.DOCKERHUB_REPOSITORY }}/kapitan
+            name=${{ needs.publish.outputs.python-version }} == '3.11' && ${{ vars.DOCKERHUB_REPOSITORY }}/kapitan || ${{ vars.DOCKERHUB_REPOSITORY }}/kapitan-py${{ needs.publish.outputs.python-version }}
           # generate Docker tags based on the following events/attributes
           tags: |
             type=raw,value=latest,enable=${{ github.ref == format('refs/heads/{0}', github.event.repository.default_branch) }}

Dockerfile

@@ -1,5 +1,6 @@
 # Build the virtualenv for Kapitan
-FROM python:3.11-slim AS python-builder
+ARG PYTHON_VERSION=3.11
+FROM python:${PYTHON_VERSION}-slim AS python-builder
 ARG TARGETARCH
 ENV TARGETARCH=${TARGETARCH:-amd64}
 
@@ -44,11 +45,12 @@ COPY ./kapitan ./kapitan
 
 RUN pip install .[gojsonnet,omegaconf,reclass-rs]
 
+ARG PYTHON_VERSION=3.11
 FROM golang:1 AS go-builder
 RUN GOBIN=$(pwd)/ go install cuelang.org/go/cmd/cue@latest
 
 # Final image with virtualenv built in previous step
-FROM python:3.11-slim
+FROM python:${PYTHON_VERSION}-slim
 
 ENV PATH="/opt/venv/bin:${PATH}"
 ENV HELM_CACHE_HOME=".cache/helm"

README.md

@@ -60,6 +60,8 @@ To build a docker image for the architecture of your machine, run `docker build
 
 To build a multi-platform image (as the CI does), follow [the docker multi-platform documentation](https://docs.docker.com/build/building/multi-platform/).
 
+To build a docker image using a specific python version, run `docker build --build-arg PYTHON_BUILDER_VERSION=<python-version> . -t you-kapitan-image`. By default the Dockerfile is pinned using python 3.11 as the python builder version.
+
 ## Related projects
 
 * [Tesoro](https://github.com/kapicorp/tesoro) - Kubernetes Admission Controller for Kapitan Secrets