ci: introduce a script to validate git commit messages

.github/workflows/ci.yml

@@ -8,17 +8,18 @@ on: [push, pull_request]
 jobs:
   lint:
     runs-on: ubuntu-latest
+    env:
+      REVISION_RANGE: "${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }}"
     steps:
       - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0 # force fetch all history
       - uses: actions/setup-python@v5
         with:
           python-version: 3.x
-      - uses: actions/cache@v4
-        with:
-          path: ~/.cache/pip
-          key: pip
-          restore-keys: pip
       - run: make lint
+      - run: make check-patches
+        if: ${{ github.event.pull_request.base.sha && github.event.pull_request.head.sha }}
 
   deploy:
     needs:
@@ -32,11 +33,6 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: 3.x
-      - uses: actions/cache@v4
-        with:
-          path: ~/.cache/pip
-          key: pip
-          restore-keys: pip
       - run: python -m pip install --upgrade build
       - run: python -m build
       - uses: pypa/gh-action-pypi-publish@release/v1

Makefile

@@ -38,6 +38,12 @@ format: $(VENV)/.stamp
 	@echo "[black]"
 	@$(in_venv) $(PYTHON) -m black -q $(PY_FILES)
 
+REVISION_RANGE ?= origin/main..
+
+.PHONY: check-patches
+check-patches:
+	@./check-patches $(REVISION_RANGE)
+
 .PHONY: tag-release
 tag-release:
 	@cur_version=`sed -En 's/^version = "(.*)"$$/\1/p' pyproject.toml` && \

check-patches

@@ -0,0 +1,134 @@
+#!/bin/sh
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (c) 2024 Robin Jarry
+
+set -eu
+
+revision_range="${1?revision range}"
+
+valid=0
+revisions=$(git rev-list --reverse "$revision_range")
+total=$(echo $revisions | wc -w)
+if [ "$total" -eq 0 ]; then
+	exit 0
+fi
+tmp=$(mktemp)
+trap "rm -f $tmp" EXIT
+
+allowed_trailers="
+Fixes
+Closes
+Link
+Cc
+Suggested-by
+Requested-by
+Reported-by
+Co-authored-by
+Signed-off-by
+Tested-by
+Reviewed-by
+Acked-by
+"
+
+n=0
+title=
+fail=false
+repo=rjarry/sosviz
+repo_url=https://github.com/$repo
+api_url=https://api.github.com/repos/$repo
+
+err() {
+	echo "error [PATCH $n/$total] '$title' $*" >&2
+	fail=true
+}
+
+check_issue() {
+	json=$(curl -f -X GET -L --no-progress-meter \
+		-H "Accept: application/vnd.github+json" \
+		-H "X-GitHub-Api-Version: 2022-11-28" \
+		"$api_url/issues/${1##*/}") || return 1
+	test "$(echo "$json" | jq -r .state)" = open
+}
+
+for rev in $revisions; do
+	n=$((n + 1))
+	title=$(git log --format='%s' -1 "$rev")
+	fail=false
+
+	if [ "$(echo "$title" | wc -m)" -gt 72 ]; then
+		err "title is longer than 72 characters, please make it shorter"
+	fi
+	if ! echo "$title" | grep -qE '^[a-z0-9,{}/_-]+: '; then
+		err "title lacks a lowercase topic prefix (e.g. 'ipv6:')"
+	fi
+	if echo "$title" | grep -qE '^[a-z0-9,{}/_-]+: [A-Z][a-z]'; then
+		err "title starts with an capital letter, please use lower case"
+	fi
+	if ! echo "$title" | grep -qE '[A-Za-z0-9]$'; then
+		err "title ends with punctuation, please remove it"
+	fi
+
+	author=$(git log --format='%an <%ae>' -1 "$rev")
+	if ! git log --format="%(trailers:key=Signed-off-by,only,valueonly,unfold)" -1 "$rev" |
+			grep -qFx "$author"; then
+		err "'Signed-off-by: $author' trailer is missing"
+	fi
+
+	for trailer in $(git log --format="%(trailers:only,keyonly)" -1 "$rev"); do
+		if ! echo "$allowed_trailers" | grep -qFx "$trailer"; then
+			err "trailer '$trailer' is misspelled or not in the sanctioned list"
+		fi
+	done
+
+	git log --format="%(trailers:key=Closes,only,valueonly,unfold)" -1 "$rev" > $tmp
+	while read -r value; do
+		if [ -z "$value" ]; then
+			continue
+		fi
+		case "$value" in
+		$repo_url/*/[0-9]*)
+			if ! check_issue "$value"; then
+				err "'$value' does not reference a valid open issue"
+			fi
+			;;
+		\#[0-9]*)
+			value=${value#\#}
+			err "please use the full issue URL: 'Closes: $repo_url/issues/$value'"
+			;;
+		*)
+			err "invalid trailer value '$value'. The 'Closes:' trailer must only be used to reference issue URLs"
+			;;
+		esac
+	done < "$tmp"
+
+	git log --format="%(trailers:key=Fixes,only,valueonly,unfold)" -1 "$rev" > $tmp
+	while read -r value; do
+		if [ -z "$value" ]; then
+			continue
+		fi
+		fixes_rev=$(echo "$value" | sed -En 's/([A-Fa-f0-9]{7,})[[:space:]]\(".*"\)/\1/p')
+		if ! git cat-file commit "$fixes_rev" >/dev/null; then
+			err "trailer 'Fixes: $value' does not refer to a known commit"
+		fi
+	done < "$tmp"
+
+	body=$(git log --format='%b' -1 "$rev")
+	body=${body%$(git log --format='%(trailers)' -1 "$rev")}
+	if [ "$(echo "$body" | wc -w)" -lt 3 ]; then
+		err "body has less than three words, please describe your changes"
+	fi
+	if ! [ "$(git log --format='%P' -1 "$rev" | wc -w)" = 1 ]; then
+		err "merge commit found, please rebase your code"
+	fi
+
+	if [ "$fail" = true ]; then
+		continue
+	fi
+	echo "ok    [PATCH $n/$total] '$title'"
+	valid=$((valid + 1))
+done
+
+echo "$valid/$total valid patches"
+if [ "$valid" -ne "$total" ]; then
+	exit 1
+fi