Automate creation of the changelog after the release build

.github/workflows/release.yml

@@ -27,6 +27,7 @@ permissions:
   id-token: write
   contents: write
   issues: write
+  pull-requests: write
 
 jobs:
   build:
@@ -35,7 +36,7 @@ jobs:
 
     steps:
     - name: Set up JDK
-      uses: actions/setup-java@v4
+      uses: actions/setup-java@v5
       with:
         java-version: 11
         distribution: temurin
@@ -47,7 +48,7 @@ jobs:
       run: ./gradlew --parallel --max-workers 2 build
 
     - name: Configure AWS Credentials
-      uses: aws-actions/configure-aws-credentials@v1
+      uses: aws-actions/configure-aws-credentials@v6
       with:
         role-to-assume: ${{ secrets.RELEASE_IAM_ROLE }}
         aws-region: us-east-1
@@ -66,7 +67,7 @@ jobs:
 
     - name: Log into Amazon ECR Public
       id: login-ecr
-      uses: docker/login-action@v1
+      uses: docker/login-action@v4
       with:
         registry: public.ecr.aws
       env:
@@ -134,12 +135,17 @@ jobs:
     permissions:
       contents: write
       issues: write
+    outputs:
+      version: ${{ steps.get_version.outputs.version }}
 
     steps:
       - name: Checkout Data Prepper
         uses: actions/checkout@v6
       - name: Get Version
-        run: grep '^version=' gradle.properties >> $GITHUB_ENV
+        id: get_version
+        run: |
+          grep '^version=' gradle.properties >> $GITHUB_ENV
+          echo "version=$(grep '^version=' gradle.properties | cut -d'=' -f2)" >> $GITHUB_OUTPUT
 
       - name: Get Approvers
         id: get_approvers
@@ -191,3 +197,50 @@ jobs:
           tag_name: 'refs/tags/${{ env.version }}'
           files: |
             release-description.yaml
+
+  generate-changelog:
+    runs-on: ubuntu-latest
+    needs: promote
+
+    steps:
+      - name: Checkout Data Prepper
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+          persist-credentials: false
+
+      - name: Fetch Tags
+        run: git fetch origin --tags
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+
+      - name: Install git-release-notes
+        run: npm install -g git-release-notes
+
+      - name: Generate Changelog
+        run: release/script/changelog/generate-changelog.sh ${{ needs.promote.outputs.version }}
+
+      - name: GitHub App token
+        id: github_app_token
+        uses: tibdex/github-app-token@v2
+        with:
+          app_id: ${{ secrets.APP_ID }}
+          private_key: ${{ secrets.APP_PRIVATE_KEY }}
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v6
+        with:
+          token: ${{ steps.github_app_token.outputs.token }}
+          add-paths: |
+            release/release-notes/data-prepper.change-log-${{ needs.promote.outputs.version }}.md
+          commit-message: 'Add Data Prepper ${{ needs.promote.outputs.version }} changelog.'
+          signoff: true
+          branch: changelog-${{ needs.promote.outputs.version }}
+          delete-branch: true
+          base: main
+          title: 'Data Prepper ${{ needs.promote.outputs.version }} changelog'
+          body: |
+            Adds the Data Prepper ${{ needs.promote.outputs.version }} changelog generated by git-release-notes.

release/script/changelog/generate-changelog.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+
+#
+# Copyright OpenSearch Contributors
+# SPDX-License-Identifier: Apache-2.0
+#
+# The OpenSearch Contributors require contributions made to
+# this file be licensed under the Apache-2.0 license or a
+# compatible open source license.
+#
+
+# Generates a changelog for a Data Prepper release using git-release-notes.
+#
+# Usage: generate-changelog.sh <version>
+#
+# The previous version is determined automatically from existing git tags.
+# Requires git-release-notes to be installed (npm install -g git-release-notes).
+
+set -e
+
+VERSION=$1
+
+if [ -z "$VERSION" ]; then
+  echo "Usage: $0 <version>"
+  echo "  <version>  The release version (e.g. 2.15.0)"
+  exit 1
+fi
+
+PREVIOUS_VERSION=$(git tag --sort=-version:refname | grep -E '^[0-9]+\.[0-9]+\.[0-9]+$' | awk -v ver="$VERSION" 'found {print; exit} $0 == ver {found=1}')
+
+if [ -z "$PREVIOUS_VERSION" ]; then
+  echo "Error: Could not determine the previous version from git tags."
+  echo "Make sure the tag '$VERSION' exists and there is an earlier release tag."
+  exit 1
+fi
+
+echo "Generating changelog for ${PREVIOUS_VERSION}..${VERSION}"
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+REPO_ROOT="$(cd "$SCRIPT_DIR/../../.." && pwd)"
+OUTPUT_FILE="${REPO_ROOT}/release/release-notes/data-prepper.change-log-${VERSION}.md"
+
+git-release-notes "${PREVIOUS_VERSION}..${VERSION}" markdown > "$OUTPUT_FILE"
+
+echo "Changelog written to $OUTPUT_FILE"