Add Makefile target for tagging a release

Signed-off-by: Yuri Shkuro <[email protected]>

Makefile

@@ -54,3 +54,21 @@ check-internal-links: clean build link-checker-setup run-link-checker
 
 check-all-links: clean build link-checker-setup
 	bin/htmltest --conf .htmltest.external.yml
+
+# only x.y.0 semver values are valid for kicking off a new release.
+SEMVER_REGEX := ^([0-9]+\.){2}0$$
+VALID_VERSION := $(shell echo "$(VERSION)" | grep -E "$(SEMVER_REGEX)")
+
+ifneq "$(VALID_VERSION)" "$(VERSION)"
+validate-version:
+	@echo "ERROR: Invalid VERSION=$(VERSION). Must be in format x.y.0."
+	@false  # Exit with an error code
+else
+validate-version:
+	@echo "VERSION=$(VERSION) is valid."
+endif
+
+# `make start-release VERSION=x.y.0
+start-release: validate-version
+	git tag release-$(VERSION)
+	git push upstream release-$(VERSION)

RELEASE.md

@@ -11,9 +11,13 @@ Before creating a new release:
     `git remote add upstream [email protected]:jaegertracing/documentation.git`
   - Make sure you are on your `main` branch.
 
-Then create a release by pushing a tag corresponding to the jaegertracing/jaeger version `release-X.Y.Z`, e.g.
+Then create a release by pushing a tag corresponding to the jaegertracing/jaeger version `release-X.Y.0`, e.g.
 
 ```shell
+make start-release VERSION=1.12.0
+
+# or manually
+
 git tag release-1.12.0
 git push upstream release-1.12.0
 ```
@@ -29,4 +33,3 @@ TODO: shouldn't the tag only specify major/minor, not patch? I don't think the p
 ### Auto-generated documentation for CLI flags
 
 The docs for the Jaeger CLI tools are generated by the automated release process described above using the Python script [`scripts/gen-cli-data.py`](./scripts/gen-cli-data.py). It uses the configuration file `data/cli/next-release/config.json` (automatically copied to `data/cli/${NEXT_VERSION}/config.json`) that describes which Jaeger binaries to include in the documentation, and which storage options each binary supports. The script invokes the `docs` command on the respective Docker images for each  binary and creates a set of YAML files under `data/cli/${NEXT_VERSION}/`, which are then used by the template engine to render the CLI docs.
-