fix: pipe blob content via stdin to avoid ARG_MAX limit in spec sync (#16510)

fix: use GPG-signed commits in spec sync workflow

Switch from unsigned GitHub API commits to GPG-signed git commits
using the aap-api-bot GPG key (OPENAPI_SPEC_SYNC_GPG_PRIVATE_KEY).

The aap-openapi-specs repo requires signed commits via org ruleset.
The previous API-based approach didn't sign commits because GitHub
only auto-signs API commits for GitHub App tokens, not user PATs.

This matches the pattern used by EDA and Gateway teams for their
spec sync workflows.

Also fixes template injection risk by using env vars instead of
direct ${{ }} expansion in shell context.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/spec-sync-on-merge.yml

@@ -117,6 +117,7 @@ jobs:
         working-directory: spec-repo
         env:
           GH_TOKEN: ${{ secrets.OPENAPI_SPEC_SYNC_TOKEN }}
+          GPG_PRIVATE_KEY: ${{ secrets.OPENAPI_SPEC_SYNC_GPG_PRIVATE_KEY }}
           COMMIT_MESSAGE: ${{ github.event.head_commit.message }}
           SPEC_REPO: ansible-automation-platform/aap-openapi-specs
           REF_NAME: ${{ github.ref_name }}
@@ -124,50 +125,44 @@ jobs:
           GITHUB_REPO: ${{ github.repository }}
           IS_NEW_FILE: ${{ steps.compare.outputs.is_new_file }}
         run: |
+          # Import GPG key and configure git for signed commits
+          echo "$GPG_PRIVATE_KEY" | gpg --batch --import 2>/dev/null
+          GPG_KEY_ID=$(gpg --list-secret-keys --keyid-format long 2>/dev/null | grep sec | head -1 | awk '{print $2}' | cut -d'/' -f2)
+          if [ -z "$GPG_KEY_ID" ]; then
+            echo "❌ Failed to import GPG key or extract key ID"
+            exit 1
+          fi
+          git config user.name "aap-api-bot"
+          git config user.email "aap-api-bot@redhat.com"
+          git config commit.gpgsign true
+          git config user.signingkey "$GPG_KEY_ID"
+
+          # Configure git to use the token for push
+          git remote set-url origin "https://x-access-token:${GH_TOKEN}@github.com/${SPEC_REPO}.git"
+
           SHORT_SHA="${GITHUB_SHA_FULL:0:7}"
           BRANCH_NAME="update-Controller-${REF_NAME}-${SHORT_SHA}"
 
+          git checkout -b "$BRANCH_NAME"
+
+          # Add and commit changes
+          git add "controller.json"
+
           if [ "${IS_NEW_FILE}" == "true" ]; then
             COMMIT_MSG="Add Controller OpenAPI spec for ${REF_NAME}"
           else
             COMMIT_MSG="Update Controller OpenAPI spec for ${REF_NAME}"
           fi
 
-          COMMIT_MSG="${COMMIT_MSG}
+          git commit -m "${COMMIT_MSG}
 
           Synced from ${GITHUB_REPO}@${GITHUB_SHA_FULL}
-          Source branch: ${REF_NAME}"
+          Source branch: ${REF_NAME}
 
-          # Create branch via API
-          BASE_SHA=$(gh api "repos/${SPEC_REPO}/git/ref/heads/${REF_NAME}" --jq '.object.sha')
-          gh api "repos/${SPEC_REPO}/git/refs" \
-            -f "ref=refs/heads/${BRANCH_NAME}" \
-            -f "sha=${BASE_SHA}"
+          Co-Authored-By: github-actions[bot] <github-actions[bot]@users.noreply.github.com>"
 
-          # Get the tree SHA from the base commit (base_tree requires a tree SHA, not a commit SHA)
-          BASE_TREE_SHA=$(gh api "repos/${SPEC_REPO}/git/commits/${BASE_SHA}" --jq '.tree.sha')
-
-          # Create blob and commit via API (commits created through the API are automatically signed by GitHub)
-          BLOB_SHA=$(gh api "repos/${SPEC_REPO}/git/blobs" \
-            -f "content=$(base64 -w 0 controller.json)" \
-            -f "encoding=base64" \
-            --jq '.sha')
-
-          TREE_SHA=$(gh api "repos/${SPEC_REPO}/git/trees" \
-            -f "base_tree=${BASE_TREE_SHA}" \
-            --input <(jq -n --arg blob "$BLOB_SHA" '{tree: [{path: "controller.json", mode: "100644", type: "blob", sha: $blob}]}') \
-            --jq '.sha')
-
-          NEW_COMMIT_SHA=$(gh api "repos/${SPEC_REPO}/git/commits" \
-            -f "message=${COMMIT_MSG}" \
-            -f "tree=${TREE_SHA}" \
-            -f "parents[]=${BASE_SHA}" \
-            --jq '.sha')
-
-          # Update branch ref to point to the new signed commit
-          gh api "repos/${SPEC_REPO}/git/refs/heads/${BRANCH_NAME}" \
-            -X PATCH \
-            -f "sha=${NEW_COMMIT_SHA}"
+          # Push branch
+          git push origin "$BRANCH_NAME"
 
           # Create PR
           PR_TITLE="[${REF_NAME}] Update Controller spec from merged commit"