signal-bot/.pre-commit-config.yaml
Krzysztof kuhy Rudnicki 37a27c6dff feat: refuse to commit personal data, learned from outside the repository
The leak this repository had was not carelessness with a secret. It was
somebody reaching for a real name because it was the example in front of
them -- a fixture built from a live database, an envelope pasted out of a
running container, a help text written while looking at the actual group.
Three different people-shaped mistakes, none of which a rule about "be
careful" would have stopped.

So it is a gate. The hard part is that the thing being checked must not
contain the list of what to refuse, or the check *is* the leak. It reads the
names at run time from outside: the photo pack's manifest, the message
database, the local .env. It never prints the word it matched, because this
output reaches CI logs. On a machine with none of that private data it says
"shapes only" out loud rather than passing quietly, and CI enforces the half
that needs nothing -- phone numbers, uuids and Signal group ids, compared
against an allowlist of values invented for the fixtures.

It runs on staged files, on the commit message -- where two of the leaks
actually travelled -- and over the whole tree in CI.

It paid for itself twice before it was wired up. The live test group's id was
in tests/test_config.py in two spellings, and truncated in three more files,
after four rounds of grepping by hand had pronounced the tree clean -- nobody
thinks to grep for base64. Then it refused the commit that introduced it,
because DOCS-privacy.md had used a real name as the example of a name.

An allowlist line may be scoped to one file, which is how the given names
that are also popes stay legal in popes.json and refused in every fixture
that has no business carrying them. The threshold is three characters,
because one of this group's given names is three characters long.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017w1HZ3cZ7neL3rFdQ6VMBA
2026-08-30 23:28:29 +02:00

149 lines
5.3 KiB
YAML

# Pre-commit hooks for signal-bot.
#
# Install with: pre-commit install
# Run manually: pre-commit run --all-files
#
# Every hook is `language: system` because the tools already live in .venv;
# pre-commit must not build isolated environments for them. fail_fast so a
# later check cannot run after an earlier one has already rejected the commit.
fail_fast: true
repos:
- repo: https://github.com/pre-commit/pre-commit-hooks
rev: v4.6.0
hooks:
- id: trailing-whitespace
args: [--markdown-linebreak-ext=md]
- id: end-of-file-fixer
- id: check-yaml
- id: check-json
- id: check-toml
- id: check-merge-conflict
- id: check-case-conflict
- id: check-executables-have-shebangs
- id: check-shebang-scripts-are-executable
- id: detect-private-key
- id: debug-statements
- id: check-ast
- id: mixed-line-ending
args: [--fix=lf]
- repo: local
hooks:
# Suppressions are blocked mechanically, not by discipline. This repo
# has zero of them and the only way it stays that way is a gate: the
# rule is "fix the finding, or ask first", and a habit is not a gate.
- id: no-noqa
name: block noqa / type:ignore comments
entry: '(?i)#\s*(noqa|type:\s*ignore)'
language: pygrep
types: [python]
- id: no-ruff-noqa
name: block file-level ruff noqa
entry: '(?i)#\s*ruff:\s*noqa'
language: pygrep
types: [python]
# This repository is public and holds a private message database. The
# database is gitignored, but three binary SQLite files reached the
# history anyway before this gate existed, so .gitignore is evidently
# not the whole defence. Exceptions go in .binary-allowlist.
# This repository is public and leaked once: real names, two phone
# numbers and a member's Signal uuid reached GitHub and only came off
# it by deleting the repository. The checker learns what to refuse from
# OUTSIDE the repo -- the photo pack, the message database, .env -- so
# the list of real names is never in the thing being checked.
- id: personal-data
name: no personal data
entry: scripts/check_personal_data.sh
language: system
types: [text]
# The same check on the commit message, because that is where two of
# the leaks actually lived.
- id: personal-data-message
name: no personal data in the commit message
entry: scripts/check_personal_data.sh --message
language: system
stages: [commit-msg]
always_run: true
pass_filenames: true
- id: no-binaries
name: no binary or image files
entry: scripts/check_no_binaries.sh
language: script
pass_filenames: true
# The shared 250-line cap. Checks only the files in the commit, so an
# unrelated commit never breaks. No baseline, no allowlist -- those are
# suppressions. The exemption list lives with the checker in ~/utils so
# this repo's idea of the rule cannot drift from every other repo's.
- id: file-length
name: file length <= 250 lines
entry: scripts/check_file_length.sh
language: system
# Four markdown namespaces (README / CLAUDE* / DOCS* / TODO*), plus the
# rule that a TODO carries "REMOVE ME AFTER FINISH" and nothing else may.
- id: md-naming
name: markdown naming convention
entry: scripts/check_md_naming.sh
language: system
files: \.md$
# Exact pins at newest stable. Runs repo-wide: a pin goes stale because
# upstream released, not because this commit touched the manifest.
- id: dependency-freshness
name: dependencies are newest stable
entry: scripts/check_dependency_freshness.sh --all
language: system
pass_filenames: false
always_run: true
- id: ruff-format
name: ruff format
entry: .venv/bin/ruff format --check
language: system
types_or: [python, pyi]
- id: ruff
name: ruff (ALL rules)
entry: .venv/bin/ruff check --force-exclude
language: system
types_or: [python, pyi]
- id: mypy
name: mypy --strict
entry: .venv/bin/mypy
language: system
pass_filenames: false
args: [signal_bot, fake_signal]
- id: shellcheck
name: shellcheck
# Same severity floor as CI: a stricter runner version must not be
# the thing that discovers a finding this hook let through.
entry: shellcheck -x --severity=style
language: system
types: [shell]
# The watchdog is bash, so pytest cannot reach it. Its own suite stubs
# curl and docker and drives every branch, including the give-up cap.
- id: watchdog-tests
name: watchdog behaviour (bash)
entry: scripts/test_watchdog.sh
language: system
pass_filenames: false
files: ^scripts/(signal_api_watchdog|test_watchdog)\.sh$
# 100% branch coverage, no omits. Runs on every commit: coverage is the
# whole point of the suite, and a partial run cannot prove it.
- id: pytest
name: pytest (100% branch coverage)
entry: .venv/bin/python -m pytest -q
language: system
pass_filenames: false
always_run: true