Add release-notes generation tooling (#2305)

Signed-off-by: Prajyot Parab <[email protected]>

Author: Prajyot-Parab

Makefile

@@ -50,16 +50,38 @@ CONVERSION_VERIFIER := $(TOOLS_BIN_DIR)/conversion-verifier
 SETUP_ENVTEST := $(TOOLS_BIN_DIR)/setup-envtest
 GOVULNCHECK := $(TOOLS_BIN_DIR)/govulncheck
 TRIVY := $(TOOLS_BIN_DIR)/trivy
+RELEASE_NOTES := $(TOOLS_BIN_DIR)/release-notes
 
 STAGING_REGISTRY ?= gcr.io/k8s-staging-capi-ibmcloud
 STAGING_BUCKET ?= artifacts.k8s-staging-capi-ibmcloud.appspot.com
 BUCKET ?= $(STAGING_BUCKET)
 PROD_REGISTRY := registry.k8s.io/capi-ibmcloud
 REGISTRY ?= $(STAGING_REGISTRY)
 RELEASE_TAG ?= $(shell git describe --abbrev=0 2>/dev/null)
+ifneq (,$(findstring -,$(RELEASE_TAG)))
+    PRE_RELEASE=true
+endif
+FULL_VERSION := $(RELEASE_TAG:v%=%)
+MAJOR_VERSION := $(shell echo $(FULL_VERSION) | sed -E 's/^([0-9]+)\.([0-9]+)\.([0-9]+).*/\1/')
+MINOR_VERSION := $(shell echo $(FULL_VERSION) | sed -E 's/^([0-9]+)\.([0-9]+)\.([0-9]+).*/\2/')
+PATCH_VERSION := $(shell echo $(FULL_VERSION) | sed -E 's/^([0-9]+)\.([0-9]+)\.([0-9]+).*/\3/')
+# if the release tag is a .0 version, use the main branch
+ifeq ($(PATCH_VERSION),0)
+	RELEASE_BRANCH ?= main
+else
+	RELEASE_BRANCH ?= release-$(MAJOR_VERSION).$(MINOR_VERSION)
+endif
+PREVIOUS_TAG ?= $(shell git tag --merged $(GIT_REMOTE_NAME)/$(RELEASE_BRANCH) -l | grep -E "^v[0-9]+\.[0-9]+\.[0-9]+$$" | sort -V | tail -n 1 2>/dev/null)
+START_SHA ?= $(shell git rev-list -n 1 $(PREVIOUS_TAG) 2>/dev/null)
+END_SHA ?= $(shell git rev-parse $(GIT_REMOTE_NAME)/$(RELEASE_BRANCH) 2>/dev/null)
+GIT_REPO_NAME ?= cluster-api-provider-ibmcloud
+GIT_ORG_NAME ?= kubernetes-sigs
+GIT_REMOTE_NAME ?= upstream
+
 PULL_BASE_REF ?= $(RELEASE_TAG) # PULL_BASE_REF will be provided by Prow
 RELEASE_ALIAS_TAG ?= $(PULL_BASE_REF)
 RELEASE_DIR := out
+RELEASE_NOTES_DIR := CHANGELOG
 OUTPUT_TYPE ?= type=registry
 
 # Go
@@ -271,6 +293,9 @@ test-cover: setup-envtest## Run tests with code coverage and code generate repor
 $(RELEASE_DIR):
 	mkdir -p $@
 
+$(RELEASE_NOTES_DIR):
+	mkdir -p $@
+
 $(ARTIFACTS):
 	mkdir -p $@
 
@@ -322,6 +347,19 @@ release-staging: ## Build and push container images to the staging bucket
 	$(MAKE) release-binaries
 	$(MAKE) upload-staging-artifacts
 
+.PHONY: release-notes
+release-notes: $(RELEASE_NOTES) $(RELEASE_NOTES_DIR) ## Generate/update release notes.
+	@echo "generating release notes from $(PREVIOUS_TAG) to $(RELEASE_TAG) with start sha $(START_SHA) and end sha $(END_SHA)"
+	@if [ -n "${PRE_RELEASE}" ]; then \
+		echo ":rotating_light: This is a RELEASE CANDIDATE. Use it only for testing purposes. If you find any bugs, file an [issue](https://github.com/kubernetes-sigs/cluster-api-provider-ibmcloud/issues/new)." > $(RELEASE_NOTES_DIR)/release-notes-$(RELEASE_TAG).md; \
+		$(RELEASE_NOTES) --org $(GIT_ORG_NAME) --repo $(GIT_REPO_NAME) --branch $(RELEASE_BRANCH) --required-author "" --start-sha $(START_SHA) --end-sha $(END_SHA) --markdown-links true --dependencies false --output $(RELEASE_NOTES_DIR)/$(RELEASE_TAG).md; \
+		(cat $(RELEASE_NOTES_DIR)/release-notes-$(RELEASE_TAG).md; echo ""; cat $(RELEASE_NOTES_DIR)/$(RELEASE_TAG).md) > $(RELEASE_NOTES_DIR)/tmp-release-notes.md; \
+		mv $(RELEASE_NOTES_DIR)/tmp-release-notes.md $(RELEASE_NOTES_DIR)/$(RELEASE_TAG).md; \
+		rm -f $(RELEASE_NOTES_DIR)/release-notes-$(RELEASE_TAG).md; \
+	else \
+		$(RELEASE_NOTES) --org $(GIT_ORG_NAME) --repo $(GIT_REPO_NAME) --branch $(RELEASE_BRANCH) --required-author "" --start-sha $(START_SHA) --end-sha $(END_SHA) --markdown-links true --output $(RELEASE_NOTES_DIR)/$(RELEASE_TAG).md; \
+	fi
+
 .PHONY: staging-manifests
 staging-manifests:
 	$(MAKE) $(RELEASE_DIR)/$(CORE_MANIFEST_FILE).yaml TAG=$(RELEASE_ALIAS_TAG)

docs/book/src/developer/release.md

@@ -8,6 +8,7 @@
     git push origin v0.2.0-alpha.3
     ```
 - Wait for the google cloud build to be finished 
+- [Prepare release notes](#prepare-release-notes)
 - Create a draft release with release notes for the tag
 - Tick the prerelease checkbox
 - Download the artifacts once cloud build is finished
@@ -31,6 +32,7 @@
     git push origin v0.1.0
     ```
 - Wait for the google cloud build to be finished
+- [Prepare release notes](#prepare-release-notes)
 - Create a draft release with release notes for the tag
 - Perform the [image promotion process](https://github.com/kubernetes/k8s.io/tree/main/k8s.gcr.io#image-promoter):
   - Clone and pull down the latest from [kubernetes/k8s.io](https://github.com/kubernetes/k8s.io)
@@ -49,3 +51,37 @@
   - Publish the drafted release
 
 > Note: In the above instructions, `v0.1.0` is the version/tag is being released
+
+### Prepare release notes
+
+1. If you don't have a GitHub token, create one by going to your GitHub settings, in [Personal access tokens](https://github.com/settings/tokens). Make sure you give the token the `repo` scope.
+
+2. Fetch the latest changes from upstream and check out the `main` branch:
+
+    ```sh
+    git fetch upstream
+    git checkout main
+    ```
+
+3. Generate release notes by running the following commands on the `main` branch:
+
+    ```sh
+    export GITHUB_TOKEN=<your GH token>
+    export RELEASE_TAG=v1.2.3 # change this to the tag of the release to be cut
+    make release-notes
+    ```
+
+4. Review the release notes file generated at `CHANGELOG/<RELEASE_TAG>.md` and make any necessary changes:
+
+  - Move items out of "Uncategorized" into an appropriate section.
+  - Change anything attributed to "k8s-cherrypick-robot" to credit the original author.
+  - Fix any typos or other errors.
+  - Add the following section with a link to the full diff:
+      ```md
+      ## The image for this release is:
+      registry.k8s.io/capi-ibmcloud/cluster-api-ibmcloud-controller:<RELEASE_TAG>
+
+      <!-- markdown-link-check-disable-next-line -->
+      Full Changelog: https://github.com/kubernetes-sigs/cluster-api-provider-ibmcloud/compare/v0.9.0...v0.10.0
+      ```
+    Be sure to replace the versions in the URL with the appropriate tags.

hack/tools/Makefile

@@ -129,3 +129,7 @@ $(GOVULNCHECK): $(BIN_DIR) go.mod go.sum ## Build a local copy of govulncheck.
 TRIVY := $(BIN_DIR)/trivy
 $(TRIVY): $(BIN_DIR) go.mod go.sum ## Build a local copy of trivy.
 	go build -tags=capibmtools -o $@ github.com/aquasecurity/trivy/cmd/trivy
+
+RELEASE_NOTES := $(BIN_DIR)/release-notes
+$(RELEASE_NOTES): $(BIN_DIR) go.mod go.sum ## Build a local copy of release-notes.
+	go build -tags=capibmtools -o $@ k8s.io/release/cmd/release-notes