changelog workflow (#315)

Author: pablo-garay

.github/workflows/changelog-build.yml

@@ -0,0 +1,73 @@
+name: 'Changelog Build (Release)'
+
+on:
+  workflow_dispatch:
+    inputs:
+      last-release-tag:
+        description: Last Git tag to start from (exclusive) (e.g. `v2.0.0`)
+        type: string
+        required: true
+      release-branch:
+        description: Release branch to build changelog on (e.g. `r2.1.0`)
+        type: string
+        required: true
+    
+jobs:
+  changelog:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout branch
+        uses: actions/checkout@v4
+        with:
+          ref: main
+          fetch-depth: 0
+
+      - name: Build Changelog
+        id: github_tag
+        uses: mikepenz/[email protected]
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          # Configuration file is setup with filters for domains
+          # owner:repo must point to current repo
+          # fromTag: Auto resolved from historical tag order (previous tag compared to current tag)
+          # toTag: Current tag reference
+          configuration: ".github/workflows/config/changelog-config.json"
+          owner: "NVIDIA"
+          repo: "NeMo"
+          ignorePreReleases: "false"
+          failOnError: "false"
+          fromTag: ${{ inputs.last-release-tag }}
+          toTag: ${{ inputs.release-branch }}
+
+      - name: Update changelog file
+        env: 
+          RELEASE_BRANCH: ${{ inputs.release-branch }}
+          CHANGELOG: ${{ steps.github_tag.outputs.changelog }}
+        shell: bash -x -e -u -o pipefail {0}
+        run: |
+          RELEASE_VERSION=${RELEASE_BRANCH#r}
+          CHANGELOG=$(echo "$CHANGELOG" | sed '/^[[:blank:]]*#/s/#/###/')
+
+          RELEASE_NOTES="## NVIDIA Neural Modules $RELEASE_VERSION
+
+          ### Detailed Changelogs:
+
+          $CHANGELOG"
+
+          printf "%s\n" "$RELEASE_NOTES" | sed '/<!-- Next changelog -->/r /dev/stdin' CHANGELOG.md > CHANGELOG.tmp.md
+
+          mv CHANGELOG.tmp.md CHANGELOG.md
+
+      - name: Inspect new changelog file
+        run: cat CHANGELOG.md
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v7
+        with:
+          commit-message: "beep boop: Update changelog"
+          title: "Update changelog for `${{ inputs.release-branch }}`"
+          signoff: true
+          sign-commits: true
+          base: main
+          branch: bot/chore/update-changelog-into-${{ inputs.release-branch }}