Allow PRs to build images (#54)

* Allow PR to build firmware

* Add a no-op step

* Run CI on any push

* Add missing `runs-on`

* Fix typo in `get-build-container-names` output

* Only push the new container if the GitHub event is itself `push`

* Only build the new container if necessary

* Move `env` variable to step output

* Only ignore a few paths instead of listing all paths to include

* Use a Python script to query the GitHub API to determine `base` and `head`

* Use correct environment variable name

* Revert "Use correct environment variable name"

This reverts commit bfc2f70.

* Revert "Use a Python script to query the GitHub API to determine `base` and `head`"

This reverts commit 7bf64ee.

* Handle `push` and `pull_request` separately

* Forgot `tag_name`

* Detect the current PR

* Remove extraneous parentheses

* Ensure CI works for both pull requests and pushes

* Fix shell script logic

* Use correct step name in `steps.`

* Oops, too many replaces

* Truncate the tag name to 16 characters

* Include the registry name in Docker steps

* Revert removal of `actions/checkout`

* Download Gecko SDKs as ZIP files

* Unzip quietly

* Fail if we must build a container in a PR

.github/workflows/build.yaml

@@ -1,16 +1,14 @@
 name: Build firmwares
 
 on:
+  pull_request:
+    paths-ignore:
+      - '.gitignore'
+      - 'README.md'
   push:
-    paths:
-      - Dockerfile
-      - .github/workflows/build.yaml
-      - manifests/**/*.yaml
-    branches:
-      - main
-    tags:
-      - '*'
-
+    paths-ignore:
+      - '.gitignore'
+      - 'README.md'
 env:
   REGISTRY: ghcr.io
 
@@ -22,39 +20,73 @@ jobs:
       packages: write
     steps:
       - uses: actions/checkout@v4.1.4
-      - name: Create container name
-        id: create-container-name
-        run: |
-          repository_owner=$(echo $GITHUB_REPOSITORY_OWNER | tr [:upper:] [:lower:])
-          image_name="${{ env.REGISTRY }}/$repository_owner/silabs-firmware-builder"
-          tag_name="${{ hashFiles('Dockerfile') }}"
-
-          echo "image_name=$image_name" >> $GITHUB_OUTPUT
-          echo "tag_name=$tag_name" >> $GITHUB_OUTPUT
-          echo "container_name=$image_name:$tag_name" >> $GITHUB_OUTPUT
       - name: Log in to the GitHub container registry
         uses: docker/login-action@v3.1.0
         with:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.repository_owner }}
           password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Read repository information
+        id: read-repo-info
+        run: |
+          if [[ $GITHUB_EVENT_NAME == "pull_request" ]]; then
+            base_image=$(echo ${{ github.event.pull_request.base.repo.full_name }} | awk '{print tolower($0)}')
+            head_image=$(echo ${{ github.event.pull_request.head.repo.full_name }} | awk '{print tolower($0)}')
+          else
+            base_image=$(echo ${{ github.repository }} | awk '{print tolower($0)}')
+            head_image=$(echo ${{ github.repository }} | awk '{print tolower($0)}')
+          fi
+
+          tag_name=$(echo "${{ hashFiles('Dockerfile') }}" | cut -c-16)
+
+          # Default to building a new container under the original repo
+          image_name=$head_image
+          build_image=true
+
+          # Check if we can use the base image (Nabu Casa)
+          if docker manifest inspect ${{ env.REGISTRY }}/$base_image:$tag_name; then
+            image_name=$base_image
+            build_image=false
+          fi
+
+          # Check if we can use the head image (if this is a PR)
+          if [[ $base_image != $head_image ]]; then
+            if docker manifest inspect ${{ env.REGISTRY }}/$head_image:$tag_name; then
+              image_name=$head_image
+              build_image=false
+            fi
+          fi
+
+          if [[ $build_image == "true" && $GITHUB_EVENT_NAME == "pull_request" ]]; then
+            echo "Cannot build a new container within a PR. Please re-run this action after $head_image:$tag_name is built."
+            exit 1
+          fi
+
+          echo "build_image=$build_image" >> $GITHUB_OUTPUT
+          echo "tag_name=$tag_name" >> $GITHUB_OUTPUT
+          echo "image_name=$image_name" >> $GITHUB_OUTPUT
+          echo "container_name=${{ env.REGISTRY }}/$image_name:$tag_name" >> $GITHUB_OUTPUT
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3.3.0
+        if: steps.read-repo-info.outputs.build_image == 'true'
       - name: Build and Push
         uses: docker/build-push-action@v5.3.0
+        if: steps.read-repo-info.outputs.build_image == 'true'
         with:
           context: .
           file: Dockerfile
-          tags: ${{ steps.create-container-name.outputs.container_name }}
-          cache-from: ${{ steps.create-container-name.outputs.image_name }}:cache-${{ steps.create-container-name.outputs.tag_name }}
-          cache-to: ${{ steps.create-container-name.outputs.image_name }}:cache-${{ steps.create-container-name.outputs.tag_name }}
+          tags: ${{ env.REGISTRY }}/${{ steps.read-repo-info.outputs.image_name }}:${{ steps.read-repo-info.outputs.tag_name }}
+          cache-from: ${{ env.REGISTRY }}/${{ steps.read-repo-info.outputs.image_name }}:cache-${{ steps.read-repo-info.outputs.tag_name }}
+          cache-to: ${{ env.REGISTRY }}/${{ steps.read-repo-info.outputs.image_name }}:cache-${{ steps.read-repo-info.outputs.tag_name }}
           push: true
     outputs:
-      container_name: ${{ steps.create-container-name.outputs.container_name }}
+      tag_name: ${{ steps.read-repo-info.outputs.tag_name }}
+      image_name: ${{ steps.read-repo-info.outputs.image_name }}
+      container_name: ${{ steps.read-repo-info.outputs.container_name }}
+
 
   list-manifests:
     name: List firmware manifests
-    needs: build-container
     runs-on: ubuntu-latest
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}

Dockerfile

@@ -24,7 +24,7 @@ RUN \
 # is known to be working with Commander_linux_x86_64_1v15p0b1306.tar.bz).
 RUN \
     curl -O https://www.silabs.com/documents/login/software/SimplicityCommander-Linux.zip \
-    && unzip SimplicityCommander-Linux.zip \
+    && unzip -q SimplicityCommander-Linux.zip \
     && tar -C /opt -xjf SimplicityCommander-Linux/Commander_linux_x86_64_*.tar.bz \
     && rm -r SimplicityCommander-Linux \
     && rm SimplicityCommander-Linux.zip
@@ -34,7 +34,7 @@ ENV PATH="$PATH:/opt/commander"
 # Install Silicon Labs Configurator (slc)
 RUN \
     curl -O https://www.silabs.com/documents/login/software/slc_cli_linux.zip \
-    && unzip -d /opt slc_cli_linux.zip \
+    && unzip -q -d /opt slc_cli_linux.zip \
     && rm slc_cli_linux.zip
 
 ENV PATH="$PATH:/opt/slc_cli"
@@ -53,13 +53,15 @@ RUN \
 
 # Gecko SDK 4.4.0
 RUN \
-    git clone --depth 1 -b v4.4.0 https://github.com/SiliconLabs/gecko_sdk.git gecko_sdk_4.4.0 \
-    && rm -rf gecko_sdk_4.4.0/.git
+    curl -o gecko_sdk_4.4.0.zip -L https://github.com/SiliconLabs/gecko_sdk/releases/download/v4.4.0/gecko-sdk.zip \
+    && unzip -q -d gecko_sdk_4.4.0 gecko_sdk_4.4.0.zip \
+    && rm gecko_sdk_4.4.0.zip
 
 # Gecko SDK 4.3.1
 RUN \
-    git clone --depth 1 -b v4.3.1 https://github.com/SiliconLabs/gecko_sdk.git gecko_sdk_4.3.1 \
-    && rm -rf gecko_sdk_4.3.1/.git
+    curl -o gecko_sdk_4.3.1.zip -L https://github.com/SiliconLabs/gecko_sdk/releases/download/v4.3.1/gecko-sdk.zip \
+    && unzip -q -d gecko_sdk_4.3.1 gecko_sdk_4.3.1.zip \
+    && rm gecko_sdk_4.3.1.zip
 
 ARG USERNAME=builder
 ARG USER_UID=1000