Files
CleanArchitecture-template/.brain/.agent/skills/engineering-advanced-skills/changelog-generator/scripts/generate_changelog.py
2026-03-12 15:17:52 +07:00

248 lines
7.7 KiB
Python
Executable File

#!/usr/bin/env python3
"""Generate changelog entries from Conventional Commits.
Input sources (priority order):
1) --input file with one commit subject per line
2) stdin commit subjects
3) git log from --from-tag/--to-tag or --from-ref/--to-ref
Outputs markdown or JSON and can prepend into CHANGELOG.md.
"""
import argparse
import json
import re
import subprocess
import sys
from dataclasses import dataclass, asdict, field
from datetime import date
from pathlib import Path
from typing import Dict, List, Optional
COMMIT_RE = re.compile(
r"^(?P<type>feat|fix|perf|refactor|docs|test|build|ci|chore|security|deprecated|remove)"
r"(?:\((?P<scope>[^)]+)\))?(?P<breaking>!)?:\s+(?P<summary>.+)$"
)
SECTION_MAP = {
"feat": "Added",
"fix": "Fixed",
"perf": "Changed",
"refactor": "Changed",
"security": "Security",
"deprecated": "Deprecated",
"remove": "Removed",
}
class CLIError(Exception):
"""Raised for expected CLI failures."""
@dataclass
class ParsedCommit:
raw: str
ctype: str
scope: Optional[str]
summary: str
breaking: bool
@dataclass
class ChangelogEntry:
version: str
release_date: str
sections: Dict[str, List[str]] = field(default_factory=dict)
breaking_changes: List[str] = field(default_factory=list)
bump: str = "patch"
def parse_args() -> argparse.Namespace:
parser = argparse.ArgumentParser(description="Generate changelog from conventional commits.")
parser.add_argument("--input", help="Text file with one commit subject per line.")
parser.add_argument("--from-tag", help="Git tag start (exclusive).")
parser.add_argument("--to-tag", help="Git tag end (inclusive).")
parser.add_argument("--from-ref", help="Git ref start (exclusive).")
parser.add_argument("--to-ref", help="Git ref end (inclusive).")
parser.add_argument("--next-version", default="Unreleased", help="Version label for the generated entry.")
parser.add_argument("--date", dest="entry_date", default=str(date.today()), help="Release date (YYYY-MM-DD).")
parser.add_argument("--format", choices=["markdown", "json"], default="markdown", help="Output format.")
parser.add_argument("--write", help="Prepend generated markdown entry into this changelog file.")
return parser.parse_args()
def read_lines_from_file(path: str) -> List[str]:
try:
return [line.strip() for line in Path(path).read_text(encoding="utf-8").splitlines() if line.strip()]
except Exception as exc:
raise CLIError(f"Failed reading --input file: {exc}") from exc
def read_lines_from_stdin() -> List[str]:
if sys.stdin.isatty():
return []
payload = sys.stdin.read()
return [line.strip() for line in payload.splitlines() if line.strip()]
def read_lines_from_git(args: argparse.Namespace) -> List[str]:
if args.from_tag or args.to_tag:
if not args.to_tag:
raise CLIError("--to-tag is required when using tag range.")
start = args.from_tag
end = args.to_tag
elif args.from_ref or args.to_ref:
if not args.to_ref:
raise CLIError("--to-ref is required when using ref range.")
start = args.from_ref
end = args.to_ref
else:
return []
range_spec = f"{start}..{end}" if start else end
try:
proc = subprocess.run(
["git", "log", range_spec, "--pretty=format:%s", "--no-merges"],
text=True,
capture_output=True,
check=True,
)
except subprocess.CalledProcessError as exc:
raise CLIError(f"git log failed for range '{range_spec}': {exc.stderr.strip()}") from exc
return [line.strip() for line in proc.stdout.splitlines() if line.strip()]
def load_commits(args: argparse.Namespace) -> List[str]:
if args.input:
return read_lines_from_file(args.input)
stdin_lines = read_lines_from_stdin()
if stdin_lines:
return stdin_lines
git_lines = read_lines_from_git(args)
if git_lines:
return git_lines
raise CLIError("No commit input found. Use --input, stdin, or git range flags.")
def parse_commits(lines: List[str]) -> List[ParsedCommit]:
parsed: List[ParsedCommit] = []
for line in lines:
match = COMMIT_RE.match(line)
if not match:
continue
ctype = match.group("type")
scope = match.group("scope")
summary = match.group("summary")
breaking = bool(match.group("breaking")) or "BREAKING CHANGE" in line
parsed.append(ParsedCommit(raw=line, ctype=ctype, scope=scope, summary=summary, breaking=breaking))
return parsed
def determine_bump(commits: List[ParsedCommit]) -> str:
if any(c.breaking for c in commits):
return "major"
if any(c.ctype == "feat" for c in commits):
return "minor"
return "patch"
def build_entry(commits: List[ParsedCommit], version: str, entry_date: str) -> ChangelogEntry:
sections: Dict[str, List[str]] = {
"Security": [],
"Added": [],
"Changed": [],
"Deprecated": [],
"Removed": [],
"Fixed": [],
}
breaking_changes: List[str] = []
for commit in commits:
if commit.breaking:
breaking_changes.append(commit.summary)
section = SECTION_MAP.get(commit.ctype)
if section:
line = commit.summary if not commit.scope else f"{commit.scope}: {commit.summary}"
sections[section].append(line)
sections = {k: v for k, v in sections.items() if v}
return ChangelogEntry(
version=version,
release_date=entry_date,
sections=sections,
breaking_changes=breaking_changes,
bump=determine_bump(commits),
)
def render_markdown(entry: ChangelogEntry) -> str:
lines = [f"## [{entry.version}] - {entry.release_date}", ""]
if entry.breaking_changes:
lines.append("### Breaking")
lines.extend([f"- {item}" for item in entry.breaking_changes])
lines.append("")
ordered_sections = ["Security", "Added", "Changed", "Deprecated", "Removed", "Fixed"]
for section in ordered_sections:
items = entry.sections.get(section, [])
if not items:
continue
lines.append(f"### {section}")
lines.extend([f"- {item}" for item in items])
lines.append("")
lines.append(f"<!-- recommended-semver-bump: {entry.bump} -->")
return "\n".join(lines).strip() + "\n"
def prepend_changelog(path: Path, entry_md: str) -> None:
if path.exists():
original = path.read_text(encoding="utf-8")
else:
original = "# Changelog\n\nAll notable changes to this project will be documented in this file.\n\n"
if original.startswith("# Changelog"):
first_break = original.find("\n")
head = original[: first_break + 1]
tail = original[first_break + 1 :].lstrip("\n")
combined = f"{head}\n{entry_md}\n{tail}"
else:
combined = f"# Changelog\n\n{entry_md}\n{original}"
path.write_text(combined, encoding="utf-8")
def main() -> int:
args = parse_args()
lines = load_commits(args)
parsed = parse_commits(lines)
if not parsed:
raise CLIError("No valid conventional commit messages found in input.")
entry = build_entry(parsed, args.next_version, args.entry_date)
if args.format == "json":
print(json.dumps(asdict(entry), indent=2))
else:
markdown = render_markdown(entry)
print(markdown, end="")
if args.write:
prepend_changelog(Path(args.write), markdown)
if args.format == "json" and args.write:
prepend_changelog(Path(args.write), render_markdown(entry))
return 0
if __name__ == "__main__":
try:
raise SystemExit(main())
except CLIError as exc:
print(f"ERROR: {exc}", file=sys.stderr)
raise SystemExit(2)