Automate Nix vendorHash updates in nix-shell-test workflow

.github/workflows/go.yml

@@ -57,6 +57,8 @@ jobs:
   nix-shell-test:
     runs-on: ubuntu-latest
     needs: go-test
+    permissions:
+      contents: write
     steps:
       - uses: actions/checkout@v4
 
@@ -66,9 +68,60 @@ jobs:
           nix_path: nixpkgs=channel:nixos-unstable
 
       - name: Check nix-shell default.nix
+        id: nix-test
+        continue-on-error: true
         run: |
           set -o pipefail
-          make test-nix 2>&1 | sed -u 's|\s\+got:|::error file=pkgs/defang/cli.nix,line=9::Replace the vendorHash in cli.nix with the correct value:|'
+          make test-nix 2>&1 | tee /tmp/nix-test-output.log
+          exit ${PIPESTATUS[0]}
+
+      - name: Update vendorHash if needed
+        if: steps.nix-test.outcome == 'failure'
+        run: |
+          # Extract the correct hash from the error output
+          NEW_HASH=$(grep 'got:' /tmp/nix-test-output.log | grep -oP 'sha256-[A-Za-z0-9+/]+=*' | head -1)
+
+          if [ -n "$NEW_HASH" ]; then
+            # Validate hash format (should be sha256- followed by 44 base64 characters)
+            if ! echo "$NEW_HASH" | grep -qE '^sha256-[A-Za-z0-9+/]{43}=$'; then
+              echo "❌ Extracted hash has invalid format: $NEW_HASH"
+              exit 1
+            fi
+
+            echo "Found new hash: $NEW_HASH"
+
+            # Update the vendorHash in cli.nix
+            OLD_HASH=$(grep -oP 'vendorHash = "\Ksha256-[A-Za-z0-9+/]+=*' pkgs/defang/cli.nix)
+            echo "Old hash: $OLD_HASH"
+
+            # Use @ as delimiter since it won't appear in base64 hashes
+            sed -i "s@vendorHash = \"$OLD_HASH\"@vendorHash = \"$NEW_HASH\"@" pkgs/defang/cli.nix
+
+            # Verify the fix works before committing
+            echo "Verifying the updated hash..."
+            if make test-nix; then
+              echo "✅ Verification successful"
+
+              # Configure git
+              git config user.name "github-actions[bot]"
+              git config user.email "github-actions[bot]@users.noreply.github.com"
+
+              # Commit and push the change
+              git add pkgs/defang/cli.nix
+              git commit -m "Update Nix vendorHash to $NEW_HASH"
+              git push
+
+              echo "✅ Updated vendorHash and committed the change"
+            else
+              echo "❌ Verification failed after updating hash"
+              exit 1
+            fi
+          else
+            echo "❌ Could not extract hash from error output"
+            echo "Last 20 lines of output:"
+            tail -20 /tmp/nix-test-output.log
+            exit 1
+          fi
 
   # go-byoc-test:
   #   runs-on: ubuntu-latest