Support multi platform check

.github/workflows/test.yml

@@ -9,7 +9,7 @@ on:
 
 jobs:
   test1:
-    name: Test-Action
+    name: Test Update Needed
     runs-on: ubuntu-22.04
     continue-on-error: true
     steps:
@@ -20,14 +20,82 @@ jobs:
         uses: ./
         with:
           base-image: library/nginx:1.21.0
-          image: nginx/nginx-ingress:1.12.0
+          image: nginx/nginx-ingress:2.1.0
       - name: Get Test Output
         run: echo "Workflow Docker Image ${{ steps.test.outputs.needs-updating }}"
       - name: Check value
-        run: echo "Needs updating"
-        if: steps.test.outputs.needs-updating == 'true'
+        run: |
+          if [[ "${{ steps.test.outputs.needs-updating }}" != "true" ]]; then
+            exit 1
+          fi
+
   test2:
-    name: Test-Action
+    name: Test Update Not Needed
+    runs-on: ubuntu-22.04
+    continue-on-error: true
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v2
+      - name: Test Action
+        id: test
+        uses: ./
+        with:
+          base-image: nginx:1.21.0
+          image: library/nginx:1.21.0
+      - name: Get Test Output
+        run: echo "Workflow Docker Image ${{ steps.test.outputs.needs-updating }}"
+      - name: Check value
+        run: |
+          if [[ "${{ steps.test.outputs.needs-updating }}" != "false" ]]; then
+            exit 1
+          fi
+
+  test3:
+    name: Test Update Needed on ARM64
+    runs-on: ubuntu-22.04
+    continue-on-error: true
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v3
+      - name: Test Action
+        id: test
+        uses: ./
+        with:
+          base-image: nginx:1.21.0
+          image: nginx/nginx-ingress:2.1.0
+          platforms: linux/arm64
+      - name: Get Test Output
+        run: echo "Workflow Docker Image ${{ steps.test.outputs.needs-updating }}"
+      - name: Check value
+        run: |
+          if [[ "${{ steps.test.outputs.needs-updating }}" != "true" ]]; then
+            exit 1
+          fi
+
+  test4:
+    name: Test Update Needed on multiple platforms
+    runs-on: ubuntu-22.04
+    continue-on-error: true
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v3
+      - name: Test Action
+        id: test
+        uses: ./
+        with:
+          base-image: nginx:1.21.0
+          image: nginx/nginx-ingress:2.1.0
+          platforms: linux/arm64,linux/amd64
+      - name: Get Test Output
+        run: echo "Workflow Docker Image ${{ steps.test.outputs.needs-updating }}"
+      - name: Check value
+        run: |
+          if [[ "${{ steps.test.outputs.needs-updating }}" != "true" ]]; then
+            exit 1
+          fi
+
+  test5:
+    name: Test Update Not Needed on multiple platforms
     runs-on: ubuntu-22.04
     continue-on-error: true
     steps:
@@ -39,8 +107,11 @@ jobs:
         with:
           base-image: nginx:1.21.0
           image: library/nginx:1.21.0
+          platforms: linux/arm64,linux/amd64
       - name: Get Test Output
         run: echo "Workflow Docker Image ${{ steps.test.outputs.needs-updating }}"
       - name: Check value
-        run: echo "Does not need updating"
-        if: steps.test.outputs.needs-updating == 'false'
+        run: |
+          if [[ "${{ steps.test.outputs.needs-updating }}" != "false" ]]; then
+            exit 1
+          fi

action.yml

@@ -9,6 +9,10 @@ inputs:
   image:
     description: "Docker image"
     required: true
+  platforms:
+    description: "Platforms to check"
+    required: false
+    default: "linux/amd64"
 outputs:
   needs-updating:
     description: "True or false"
@@ -18,7 +22,7 @@ runs:
   steps:
     - id: run-script
       run: |
-        result=$(base=${{ inputs.base-image }} image=${{ inputs.image }} ${{ github.action_path }}/docker.sh)
+        result=$(base=${{ inputs.base-image }} image=${{ inputs.image }} platforms=${{ inputs.platforms }} ${{ github.action_path }}/docker.sh)
         echo "result=${result}" >>$GITHUB_OUTPUT
       shell: bash
 

docker.sh

@@ -5,50 +5,132 @@ set -o errexit
 set -o pipefail
 if [ "${TRACE-0}" -eq 1 ]; then set -o xtrace; fi
 
+error() {
+    # print error and exit
+    printf "Error: $1\n" >&2
+    exit 1
+
+}
+
+get_manifests() {
+    local repo=$1
+    local digest=$2
+    local token=$3
+
+    manifest_list=$(curl -sSL -H "Authorization: Bearer $token" \
+        -H "Accept: application/vnd.docker.distribution.manifest.list.v2+json,application/vnd.oci.image.index.v1+json" \
+        "https://index.docker.io/v2/${repo}/manifests/${digest}" 2>/dev/null)
+
+    if jq -e -r '.errors[0].code' <<<"$manifest_list" >/dev/null; then
+        error_code=$(jq -r '.errors[0].code' <<<"$manifest_list")
+        message=$(jq -r '.errors[0].message' <<<"$manifest_list")
+        error "Response from $repo\n code: $error_code\n message: $message"
+    fi
+
+    jq -r '[.manifests[] | select(.platform.architecture | contains ("unknown") | not) | {digest: .digest, platform: (.platform.os +"/"+ .platform.architecture)}]' <<<"$manifest_list"
+
+}
+
 get_layers() {
     local repo=$1
     local digest=$2
-    local token
-    token=$(get_token "$repo")
+    local token=$3
 
-    digestOutput=$(curl -H "Authorization: Bearer $token" \
-        -H "Accept: application/vnd.docker.distribution.manifest.v2+json" \
+    digestOutput=$(curl -sSL -H "Authorization: Bearer $token" \
+        -H "Accept: application/vnd.docker.distribution.manifest.v1+json,application/vnd.oci.image.manifest.v1+json" \
         "https://index.docker.io/v2/${repo}/manifests/${digest}" 2>/dev/null)
-    
+
     if jq -e -r '.errors[0].code' <<<"$digestOutput" >/dev/null; then
-        jq -r '.errors[0].code' <<<"$digestOutput"
-    else
-        jq -r '[.layers[].digest]' <<<"$digestOutput"
+        error_code=$(jq -r '.errors[0].code' <<<"$digestOutput")
+        message=$(jq -r '.errors[0].message' <<<"$digestOutput")
+        error "Response from $repo\n code: $error_code\n message: $message"
     fi
+
+    jq -r '[.layers[].digest]' <<<"$digestOutput"
+
 }
 
 get_token() {
     local repo=$1
     local url
     url="https://auth.docker.io/token?service=registry.docker.io&scope=repository:${repo}:pull"
-    curl "$url" 2>/dev/null | jq -r '.token'
+    curl -fsSL "$url" 2>/dev/null | jq -r '.token'
 }
 
-# if we get a "UNAUTHORIZED" response and the $base does not match a image with username -> fallback to a version with "library" as prefix
-retry_if_necessary() {
+check_if_library() {
     local IMAGE_PATTERN_WITH_USERNAME="^.+/.+$"
     local repo=$1
-    local digest=$2
-    local result
+    local token
 
-    result=$(get_layers "$repo" "$digest")
+    token=$(get_token "$repo")
+
+    code=$(curl --write-out %{http_code} -sSL --output /dev/null -H "Authorization: Bearer $token" \
+        "https://index.docker.io/v2/${repo}/tags/list" 2>/dev/null)
+
+    if [[ $code != 200 ]]; then
+
+        if ! [[ $repo =~ $IMAGE_PATTERN_WITH_USERNAME ]]; then
+            repo="library/$repo"
+
+            token=$(get_token "$repo")
 
-    if [[ $result == "UNAUTHORIZED" ]] && ! [[ $repo =~ $IMAGE_PATTERN_WITH_USERNAME ]] ; then
-        result=$(get_layers "library/$repo" "$digest")
+            code=$(curl --write-out %{http_code} -sSL --output /dev/null -H "Authorization: Bearer $token" \
+                "https://index.docker.io/v2/${repo}/tags/list" 2>/dev/null)
+
+        fi
+
+        if [[ $code != 200 ]]; then
+            error "Response code from $repo was $code"
+        fi
     fi
 
-    echo "$result"
+    result=("$repo" "$token")
 }
 
 IFS=: read base base_tag <<<$base
 IFS=: read image image_tag <<<$image
 
-layers_base=$(retry_if_necessary $base ${base_tag:-latest})
-layers_image=$(retry_if_necessary $image ${image_tag:-latest})
+check_if_library "$base"
+base_repo=${result[0]}
+base_token=${result[1]}
+manifests_base=$(get_manifests $base_repo ${base_tag:-latest} $base_token)
+
+check_if_library "$image"
+image_repo=${result[0]}
+image_token=${result[1]}
+manifests_image=$(get_manifests $image_repo ${image_tag:-latest} $image_token)
+
+diff=false
+# loop through plafforms split by comma
+for platform in $(echo $platforms | tr ',' ' '); do
+    # get the digest for the platform
+    digest_base=$(jq -r ".[] | select(.platform == \"$platform\") | .digest" <<<"$manifests_base")
+
+    # if the digest is empty, then the platform is not present in the base image
+    if [ -z "$digest_base" ]; then
+        error "Platform $platform not found in the base image $base"
+    fi
+
+    # get the digest for the platform
+    digest_image=$(jq -r ".[] | select(.platform == \"$platform\") | .digest" <<<"$manifests_image")
+
+    # if the digest is empty, then the platform is not present in the image
+    if [ -z "$digest_image" ]; then
+        error "Platform $platform not found in the image $image"
+    fi
+
+    # get the layers for the base
+    layers_base=$(get_layers $base_repo $digest_base $base_token)
+
+    # get the layers for the image
+    layers_image=$(get_layers $image_repo $digest_image $image_token)
+
+    diff=$(jq '.base-.image | .!=[]' <<<"{\"base\": $layers_base, \"image\": $layers_image }")
+
+    if [[ "$diff" == "true" ]]; then
+        break
+    fi
+
+done
 
-jq '.base-.image | .!=[]' <<<"{\"base\": $layers_base, \"image\": $layers_image }"
+echo "$diff"