chore(operator): adds the workflow for release-please (#12450)

.github/workflows/operator-check-prepare-release-commit.yml

@@ -0,0 +1,42 @@
+name: operator-check-prepare-release-commit
+
+on:
+  pull_request:
+    paths:
+      - 'operator/**'
+    branches:
+      - master
+
+jobs:
+  check-commit:
+    runs-on: ubuntu-latest
+    if: |
+      github.event.pull_request.head.ref == 'release-please--branches--master--components--operator' && 
+      contains(github.event.pull_request.title, 'chore( operator): community release')
+    steps:
+      - name: Extract release version
+        id: pr_semver
+        run: |
+          PR_TITLE="${{ github.event.pull_request.title }}"
+          SEMVER=$(echo "$PR_TITLE" | sed -n 's/^chore( operator): community release \([0-9]\+\.[0-9]\+\.[0-9]\+\)$/\1/p')
+          echo "semver=$SEMVER" >> $GITHUB_OUTPUT
+
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          ref: master
+          path: "release"
+
+      - name: Check main commits for prepare release commit
+        id: check_commit
+        env:
+          GH_TOKEN: ${{ secrets.GH_TOKEN }}
+        working-directory: "release"
+        run: |
+          COMMIT=$(gh search commits "chore(operator): prepare community release v${{ steps.pr_semver.outputs.semver }}")
+          if [ -n "$COMMIT" ]; then
+            echo "Prepare release commit found."
+          else
+            echo "No prepare release commit found for the release version ${{ steps.pr_semver.outputs.semver }}"
+            exit 1
+          fi

.github/workflows/operator-release-please.yml

@@ -0,0 +1,42 @@
+name: operator-release-please
+
+on:
+  push:
+    paths:
+      - 'operator/**'
+    branches:
+      - master
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  releasePlease:
+    runs-on: ubuntu-latest
+    outputs:
+      release_created: ${{ steps.release.outputs.operator--release_created }}
+      release_name: ${{ steps.release.outputs.operator--tag_name }}
+    steps:
+      - uses: google-github-actions/release-please-action@v4
+        id: release
+        with:
+          path: operator
+          config-file: operator/release-please-config.json
+          token: ${{ secrets.GH_TOKEN }}
+  publishRelease:
+    needs:
+    - "releasePlease"
+    runs-on: ubuntu-latest
+    if: ${{ needs.releasePlease.outputs.release_created }}
+    steps:
+      - name: "pull code to release"
+        uses: "actions/checkout@v4"
+        with:
+          path: "release"
+      - name: "publish release"
+        env:
+          GH_TOKEN: ${{ secrets.GH_TOKEN }}
+        working-directory: "release"
+        run: |
+          gh release edit "${{ needs.releasePlease.outputs.release_name }}" --draft=false --latest=false

.release-please-manifest.json

@@ -1,3 +1,4 @@
 {
-  ".": "3.0.0"
+  ".": "3.0.0",
+  "operator": "0.6.0"
 }

operator/docs/operator/release.md

@@ -0,0 +1,76 @@
+---
+title: "Release operations"
+description: "Documentation on how the operator release process works"
+lead: ""
+date: 2023-04-01T09:00:00+00:00
+lastmod: 2023-04-01T09:00:00+00:00
+draft: false
+images: []
+menu:
+  docs:
+    parent: "operator"
+weight: 100
+toc: true
+---
+
+This document will go over the design of the release process for the Loki Operator and how to release it.
+
+# Design
+
+To release Loki Operator we need the following:
+1. Bump the Loki Operator version and generate the bundle manifests with `make bundle-all`;
+2. Update the CHANGELOG.md with the new version;
+3. Create a release tag and a release on GitHub;
+4. Open two PRs to [k8s-operatorhub/community-operators](https://github.com/k8s-operatorhub/community-operators) and [redhat-openshift-ecosystem/community-operators-prod](https://github.com/redhat-openshift-ecosystem/community-operators-prod) with the contents of the new bundles;
+
+Loki Operator uses the GitHub [action release-please](https://github.com/google-github-actions/release-please-action) to automate steps 2 and 3. Furthermore, to automate step 4 we use a workflow that is triggered when a release tag is created.
+
+In the following sections, we will go over how the workflows are configured.
+
+## release-please
+
+release-please automates CHANGELOG generation, the creation of GitHub releases, and version bumps. It does so by parsing the git history, looking for Conventional Commit messages, and creating release PRs. Once a release PR is merged release-please will create the release and it will again wait for a releasable unit before opening the next release PR. A releasable unit is a commit with one of the following prefixes: "feat", "fix", and "deps".
+
+The workflow that is responsible for the operator release-please is `.github/workflows/operator-release-please.yml`. Note that the operator release-please process is different from the one used by Loki. The operator release-please configuration lives in `operator/release-please-config.json`.
+
+Useful links:
+- release-please [customizing releases documentation](https://github.com/googleapis/release-please/blob/main/docs/customizing.md)
+- release-please [config documentation](https://github.com/googleapis/release-please/blob/main/docs/manifest-releaser.md#configfile)
+
+The following sub-section contains some notes on the Loki operator release-please configuration:
+- Use of `bump-minor-pre-major` and `bump-patch-for-minor-pre-major`;
+- Use of `draft`;
+- Preventing merging the release-please PR without updating the manifests;
+
+### Use of `bump-minor-pre-major` and `bump-patch-for-minor-pre-major` 
+
+Since the operator is still pre `v1.0.0` we are leveraging `bump-minor-pre-major` and `bump-patch-for-minor-pre-major` so that merging "feat", "fix", and "deps" commits will only bump a patch version and merging "feat!" and "fix!" will bump the minor version.
+
+As of writing, the operator release-please will only act on merges to `main`. This means that we can support the following release scenarios:
+- Case 1: Release a patch version of v0.Y.x+1 with the diff from v0.Y.x. This is only supported until a breaking feature gets merged to `main`.
+- Case 2: Release a new minor version v0.Y+1.0 with the diff from v0.Y.x
+
+### Use of `draft`
+
+Since the operator shares the same repo with Loki, we want to make sure that, when we create a release of the operator we don't that release to `latest`, otherwise it would look like the latest release from the operator was Loki's latest release. Unfortunately, release-please doesn't provide a way to disable this, so instead we enable `draft`. `draft` makes it so releases created by release-please are only created in draft. We then use a step that will publish the release without setting it to the latest.
+
+### Preventing merging the release-please PR without updating the manifests
+
+Since step 1. is currently not automated and disconnected from release-please we have put in place a workflow in `.github/workflows/operator-check-prepare-release-commit.yml` that runs on release-please PRs. This workflow is responsible for making sure that in master exists a commit with the message `chore(operator): prepare community release v$VERSION`. Once we automate step 1. we should be able to remove this workflow.
+
+## Publish release to operatorhubs
+
+To publish a community release of Loki Operator to the community hubs we leverage the workflow in `.github/workflows/operator-publish-operator-hub.yml` this workflow is set to trigger on tag creation that matches `operator/`.
+
+This workflow will then use a workflow `.github/workflows/operator-reusable-hub-release.yml` that's responsible for:
+- Creating on the folder `operators/loki-operator/` a new folder with the manifests for the new version;
+- Adding the ocp supported version annotation to the `metadata.yaml` file only in the OpenShift community repo;
+- Creating a PR for the appropriate community repo.
+
+# Releasing
+
+1. Create a PR to bump the version (i.e https://github.com/grafana/loki/pull/12246), be careful with the commit message;
+2. Re-triggering the action `operator-publish-operator-hub` on the release-please PR;
+3. Merging the release-please PR (i.e TBD );
+4. Grafana bot will automatically open a PRs to [k8s-operatorhub/community-operators](https://github.com/k8s-operatorhub/community-operators) and [redhat-openshift-ecosystem/community-operators-prod](https://github.com/redhat-openshift-ecosystem/community-operators-prod);
+

operator/release-please-config.json

@@ -0,0 +1,16 @@
+{
+    "bootstrap-sha": "d298093baa58fd31e1fe73544cea0408eb744710",
+    "bump-minor-pre-major": true,
+    "bump-patch-for-minor-pre-major": true,
+    "include-component-in-tag": true,
+    "draft": true,
+    "tag-separator": "/",
+    "packages": {
+        "operator": {
+            "component": "operator",
+            "release-type": "go",
+            "pull-request-title-pattern": "chore(${component}): community release ${version}",
+            "changelog-path": "CHANGELOG.md"
+        }
+    }
+}