[CI] Add retry logic to artifact download action

Author: DenzelPenzel

.github/actions/download-artifact-extract/action.yml

@@ -25,24 +25,67 @@ inputs:
     description: "Whether to remove downloaded artifacts after copying (true/false)"
     required: false
     default: "false"
+  max-retries:
+    description: "Maximum number of retry attempts for artifact download (total attempts = max-retries + 1)"
+    required: false
+    default: "2"
+  retry-delay-seconds:
+    description: "Delay in seconds between retry attempts"
+    required: false
+    default: "10"
 
 runs:
   using: "composite"
   steps:
     - name: Download artifact
       shell: bash
+      env:
+        ARTIFACT_NAME: ${{ inputs.artifact-name }}
+        GH_TOKEN: ${{ inputs.gh-token }}
+        RUN_ID: ${{ inputs.run-id }}
+        EXTRACT_PATH: ${{ inputs.extract-path }}
+        MAX_RETRIES: ${{ inputs.max-retries }}
+        RETRY_DELAY: ${{ inputs.retry-delay-seconds }}
       run: |
-        echo "::group::📦 Downloading ${{ inputs.artifact-name }}"
-        echo "Artifact: ${{ inputs.artifact-name }}"
-        echo "Run ID: ${{ inputs.run-id }}"
-        echo "::endgroup::"
-    
-    - uses: actions/download-artifact@fa0a91b85d4f404e444e00e005971372dc801d16 # v4.1.8
-      with:
-        name: ${{ inputs.artifact-name }}
-        github-token: ${{ inputs.gh-token }}
-        run-id: ${{ inputs.run-id }}
-        path: ${{ inputs.extract-path }}
+        echo "::group::📦 Downloading $ARTIFACT_NAME"
+        echo "Artifact: $ARTIFACT_NAME"
+        echo "Run ID: $RUN_ID"
+        echo "Max retries: $MAX_RETRIES"
+        
+        # Create extract path if it doesn't exist
+        mkdir -p "$EXTRACT_PATH"
+        
+        ATTEMPT=1
+        MAX_ATTEMPTS=$((MAX_RETRIES + 1))
+        CURRENT_DELAY=$RETRY_DELAY
+        
+        while [ $ATTEMPT -le $MAX_ATTEMPTS ]; do
+          echo ""
+          echo "📥 Attempt $ATTEMPT of $MAX_ATTEMPTS..."
+          
+          # Use gh CLI to download artifact
+          if gh run download "$RUN_ID" \
+            --name "$ARTIFACT_NAME" \
+            --dir "$EXTRACT_PATH" \
+            --repo "$GITHUB_REPOSITORY"; then
+            echo "✅ Successfully downloaded artifact on attempt $ATTEMPT"
+            echo "::endgroup::"
+            exit 0
+          fi
+          
+          if [ $ATTEMPT -lt $MAX_ATTEMPTS ]; then
+            echo "::warning::Attempt $ATTEMPT failed, retrying in ${CURRENT_DELAY}s (exponential backoff)..."
+            sleep "$CURRENT_DELAY"
+            # Exponential backoff: double the delay for next attempt
+            CURRENT_DELAY=$((CURRENT_DELAY * 2))
+          else
+            echo "::error::❌ All $MAX_ATTEMPTS attempts failed to download artifact: $ARTIFACT_NAME"
+            echo "::endgroup::"
+            exit 1
+          fi
+          
+          ATTEMPT=$((ATTEMPT + 1))
+        done
 
     - name: Extract artifact
       shell: bash

.github/workflows/zombienet_cumulus.yml

@@ -80,11 +80,12 @@ jobs:
       - name: Checkout
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
-      - uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6.0.0
+      - name: Download test parachain artifact
         if: ${{ matrix.test.needs-wasm-binary }}
+        uses: ./.github/actions/download-artifact-extract
         with:
-          name: build-test-parachain-${{ needs.preflight.outputs.SOURCE_REF_SLUG }}
-          github-token: ${{ secrets.GITHUB_TOKEN }}
+          artifact-name: build-test-parachain-${{ needs.preflight.outputs.SOURCE_REF_SLUG }}
+          gh-token: ${{ secrets.GITHUB_TOKEN }}
           run-id: ${{ needs.preflight.outputs.BUILD_RUN_ID }}
 
       - name: zombienet_test