Fix retrieving manifest for single platform (#23)

Author: lucacome

.github/workflows/test.yml

@@ -14,7 +14,6 @@ jobs:
   test1:
     name: Test Update Needed
     runs-on: ubuntu-22.04
-    continue-on-error: true
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v3
@@ -35,7 +34,6 @@ jobs:
   test2:
     name: Test Update Not Needed
     runs-on: ubuntu-22.04
-    continue-on-error: true
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v3
@@ -56,7 +54,6 @@ jobs:
   test3:
     name: Test Update Needed on ARM64
     runs-on: ubuntu-22.04
-    continue-on-error: true
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v3
@@ -78,7 +75,6 @@ jobs:
   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
@@ -100,7 +96,6 @@ jobs:
   test5:
     name: Test Update Not Needed on multiple platforms
     runs-on: ubuntu-22.04
-    continue-on-error: true
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v3
@@ -118,3 +113,23 @@ jobs:
           if [[ "${{ steps.test.outputs.needs-updating }}" != "false" ]]; then
             exit 1
           fi
+
+  test6:
+    name: Test single platform
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v3
+      - name: Test Action
+        id: test
+        uses: ./
+        with:
+          base-image: alpine:latest
+          image: lucacome/alpine-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 }}" != "false" ]]; then
+            exit 1
+          fi

docker.sh

@@ -17,8 +17,8 @@ get_manifests() {
     local digest=$2
     local token=$3
 
-    manifest_list=$(curl -sSL -H "Authorization: Bearer $token" \
-        -H "Accept: application/vnd.docker.distribution.manifest.list.v2+json,application/vnd.oci.image.index.v1+json" \
+    manifest_list=$(curl -sSL --dump-header headers -H "Authorization: Bearer $token" \
+        -H "Accept: application/vnd.docker.distribution.manifest.list.v2+json,application/vnd.oci.image.index.v1+json,application/vnd.docker.distribution.manifest.v2+json,application/vnd.oci.image.manifest.v1+json" \
         "https://index.docker.io/v2/${repo}/manifests/${digest}" 2>/dev/null)
 
     if jq -e -r '.errors[0].code' <<<"$manifest_list" >/dev/null; then
@@ -27,6 +27,13 @@ get_manifests() {
         error "Response from $repo\n code: $error_code\n message: $message"
     fi
 
+    headers=$(cat headers | awk -F ': ' '{sub(/\r/,"\n",$2); print $1","$2}' | grep 'docker-content-digest\|content-type' | jq -R 'split(",") | {(if .[0] == "content-type" then "type" else "digest" end): .[1]}' | jq -s 'reduce .[] as $item ({}; . * $item)')
+    manifest_v2=$(jq -r '. | select(.type == "application/vnd.docker.distribution.manifest.v2+json" or .type == "application/vnd.oci.image.manifest.v1+json") | [{digest: .digest, platform: "linux/amd64"}]' <<<"$headers")
+    if [ ! -z "$manifest_v2" ]; then
+        echo "$manifest_v2"
+        return
+    fi
+
     jq -r '[.manifests[] | select(.platform.architecture | contains ("unknown") | not) | {digest: .digest, platform: (.platform.os +"/"+ .platform.architecture)}]' <<<"$manifest_list"
 
 }
@@ -37,7 +44,7 @@ get_layers() {
     local token=$3
 
     digestOutput=$(curl -sSL -H "Authorization: Bearer $token" \
-        -H "Accept: application/vnd.docker.distribution.manifest.v1+json,application/vnd.oci.image.manifest.v1+json" \
+        -H "Accept: application/vnd.docker.distribution.manifest.v2+json,application/vnd.oci.image.manifest.v1+json" \
         "https://index.docker.io/v2/${repo}/manifests/${digest}" 2>/dev/null)
 
     if jq -e -r '.errors[0].code' <<<"$digestOutput" >/dev/null; then
@@ -102,7 +109,7 @@ manifests_image=$(get_manifests $image_repo ${image_tag:-latest} $image_token)
 
 diff=false
 # loop through plafforms split by comma
-for platform in $(echo $platforms | tr ',' ' '); do
+for platform in $(echo $platforms | tr -s ',' ' '); do
     # get the digest for the platform
     digest_base=$(jq -r ".[] | select(.platform == \"$platform\") | .digest" <<<"$manifests_base")