From 886d729fc4db2703fdc343309b1064e17f02e108 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Emil=20Gardstr=C3=B6m?= <emil.gardstrom@gmail.com>
Date: Tue, 7 Jun 2022 17:27:36 +0200
Subject: [PATCH] add simple labels to the images

---
 .github/workflows/ci.yml | 28 +++++++++++++++++++++++++++-
 build-docker-image.sh    | 10 +++++++++-
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 237bdfc89..ca5827f3f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -205,6 +205,17 @@ jobs:
       - name: Set up Docker Buildx
         if: runner.os == 'Linux'
         uses: docker/setup-buildx-action@v1
+      - name: Docker Meta
+        if: runner.os == 'Linux'
+        id: docker-meta
+        uses: docker/metadata-action@v4
+        with:
+          images: |
+            # This is only a placeholder name, we don't actually use this information.
+            name=cross
+          labels: |
+            org.opencontainers.image.title=cross (for ${{ matrix.target }})
+            org.opencontainers.image.licenses=MIT OR Apache-2.0
       - name: Build and push Docker image
         id: build-docker-image
         if: runner.os == 'Linux'
@@ -212,6 +223,7 @@ jobs:
         run: ./build-docker-image.sh "${TARGET}"
         env:
           TARGET: ${{ matrix.target }}
+          LABELS: ${{ steps.docker-meta.outputs.labels }}
         shell: bash
       - name: Set Docker image for test
         if: steps.build-docker-image.outputs.image
@@ -250,7 +262,20 @@ jobs:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
-
+      - name: Docker Meta
+        if: >
+          runner.os == 'Linux' && (
+            github.ref == format('refs/heads/{0}', github.event.repository.default_branch) ||
+            startsWith(github.ref, 'refs/tags/v')
+          )
+        id: docker-meta2
+        uses: docker/metadata-action@v4
+        with:
+          images: |
+            name=${{ steps.build-docker-image.outputs.image }}
+          labels: |
+            org.opencontainers.image.title=cross (for ${{ matrix.target }})
+            org.opencontainers.image.licenses=MIT OR Apache-2.0
       - name: Push image to GitHub Container Registry
         if: >
           runner.os == 'Linux' && (
@@ -260,6 +285,7 @@ jobs:
         run: ./build-docker-image.sh --push "${TARGET}"
         env:
           TARGET: ${{ matrix.target }}
+          LABELS: ${{ steps.docker-meta2.outputs.labels }}
         shell: bash
 
   publish:
diff --git a/build-docker-image.sh b/build-docker-image.sh
index bf2b7d0da..8b372a3bf 100755
--- a/build-docker-image.sh
+++ b/build-docker-image.sh
@@ -79,8 +79,16 @@ run() {
     build_args+=(--tag "${tag}")
   done
 
-  docker buildx build "${build_args[@]}" -f "${dockerfile}" --progress plain .
+  if [ -n "${LABELS:-}" ]; then
+    local labels
+    mapfile -t labels -d '' <<< "${LABELS}"
+    for label in "${labels[@]}"; do
+      build_args+=(--label "${label}")
+    done
+  fi
 
+  docker buildx build "${build_args[@]}" -f "${dockerfile}" --progress plain .
+  docker inspect "${tags[0]}" | jq -C .[0].Config.Labels
   if [[ -n "${GITHUB_ACTIONS-}" ]]; then
     echo "::set-output name=image::${tags[0]}"
   fi