mirror of
https://github.com/kevinveenbirkenbach/docker-volume-backup.git
synced 2026-08-01 12:34:50 +00:00
Kevin Veen-Birkenbach
d4317827bd
Backing up a live volume with rsync copies a moving target: a database
written to mid-copy lands on disk in a state no engine ever committed.
Stopping the container avoids that at the cost of downtime.
A snapshot removes both. `--snapshot {btrfs,zfs}` with `--snapshot-subject`
freezes the docker root once per run, and every volume copy is then read
from that frozen tree while the containers keep serving. A restore of such
a copy is an ordinary crash recovery, which every supported engine performs
on its own at startup.
An unsupported filesystem or an unknown snapshot kind fails loudly rather
than degrading to a live copy, since a silent fallback would return exactly
the torn backup the mode exists to prevent. `--shutdown` is rejected
alongside `--snapshot` instead of being ignored: under a snapshot no
container is ever stopped, so accepting the flag would promise downtime
semantics the run does not deliver.
Copies out of a snapshot skip rsync's --checksum verification. The source
is immutable for the lifetime of the copy, so size-and-mtime cannot race,
and dropping the second full read roughly halves the I/O per volume.
backup/app.py grew past what one module could carry and is split into
layout, policy and dumps along the lines it already had internally.
Tests: unit coverage for the new snapshot, layout, policy, volume and cli
units; e2e cases drive real btrfs, zfs and ext4 filesystems on loop devices
in a privileged container, including a MariaDB that is written to across
the snapshot and must recover from the restored copy without losing a
committed row. CI installs zfs and sets E2E_REQUIRE_FILESYSTEMS so a
missing kernel module fails the build instead of silently skipping a
filesystem.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
214 lines
6.8 KiB
Python
214 lines
6.8 KiB
Python
from __future__ import annotations
|
|
|
|
import tempfile
|
|
import unittest
|
|
from pathlib import Path
|
|
from typing import List
|
|
from unittest.mock import patch
|
|
|
|
from .compose_fixture import setup_compose_dir as _setup_compose_dir
|
|
|
|
|
|
class TestCompose(unittest.TestCase):
|
|
@classmethod
|
|
def setUpClass(cls) -> None:
|
|
from baudolo.backup import compose as mod
|
|
|
|
cls.compose_mod = mod
|
|
|
|
def test_find_compose_file_supports_all_valid_names_case_insensitive(self) -> None:
|
|
with tempfile.TemporaryDirectory() as td:
|
|
tmp_path = Path(td)
|
|
|
|
variants = [
|
|
"compose.yml",
|
|
"compose.yaml",
|
|
"docker-compose.yml",
|
|
"docker-compose.yaml",
|
|
"docker-compose.yAml",
|
|
]
|
|
|
|
for i, name in enumerate(variants):
|
|
d = _setup_compose_dir(
|
|
tmp_path,
|
|
name=f"project{i}",
|
|
compose_name=name,
|
|
)
|
|
found = self.compose_mod._find_compose_file(str(d))
|
|
self.assertIsNotNone(found)
|
|
self.assertEqual(found.name, name)
|
|
|
|
def test_find_compose_file_returns_none_when_missing(self) -> None:
|
|
with tempfile.TemporaryDirectory() as td:
|
|
tmp_path = Path(td)
|
|
d = tmp_path / "empty"
|
|
d.mkdir(parents=True, exist_ok=True)
|
|
|
|
found = self.compose_mod._find_compose_file(str(d))
|
|
self.assertIsNone(found)
|
|
|
|
def test_build_cmd_uses_wrapper_when_present(self) -> None:
|
|
with tempfile.TemporaryDirectory() as td:
|
|
tmp_path = Path(td)
|
|
d = _setup_compose_dir(
|
|
tmp_path,
|
|
with_override=True,
|
|
with_ca_override=True,
|
|
env_layout=".env",
|
|
)
|
|
|
|
def fake_which(name: str):
|
|
if name == "compose":
|
|
return "/usr/local/bin/compose"
|
|
return None
|
|
|
|
with patch.object(self.compose_mod.shutil, "which", fake_which):
|
|
cmd = self.compose_mod._build_compose_cmd(str(d), ["up", "-d"])
|
|
|
|
self.assertEqual(
|
|
cmd,
|
|
[
|
|
"/usr/local/bin/compose",
|
|
"--chdir",
|
|
str(d.resolve()),
|
|
"--",
|
|
"up",
|
|
"-d",
|
|
],
|
|
)
|
|
|
|
def test_build_cmd_fallback_uses_plain_docker_compose_chdir(self) -> None:
|
|
with tempfile.TemporaryDirectory() as td:
|
|
tmp_path = Path(td)
|
|
d = _setup_compose_dir(
|
|
tmp_path,
|
|
with_override=True,
|
|
with_ca_override=True,
|
|
env_layout=".env",
|
|
)
|
|
|
|
def fake_which(name: str):
|
|
if name == "compose":
|
|
return None
|
|
if name == "docker":
|
|
return "/usr/bin/docker"
|
|
return None
|
|
|
|
with patch.object(self.compose_mod.shutil, "which", fake_which):
|
|
cmd = self.compose_mod._build_compose_cmd(
|
|
str(d), ["up", "-d", "--force-recreate"]
|
|
)
|
|
|
|
expected: List[str] = [
|
|
"/usr/bin/docker",
|
|
"compose",
|
|
"--chdir",
|
|
str(d.resolve()),
|
|
"up",
|
|
"-d",
|
|
"--force-recreate",
|
|
]
|
|
self.assertEqual(cmd, expected)
|
|
|
|
def test_hard_restart_calls_run_twice_with_correct_cmds_wrapper(self) -> None:
|
|
with tempfile.TemporaryDirectory() as td:
|
|
tmp_path = Path(td)
|
|
d = _setup_compose_dir(tmp_path, name="mailu", env_layout=".env")
|
|
|
|
def fake_which(name: str):
|
|
if name == "compose":
|
|
return "/usr/local/bin/compose"
|
|
return None
|
|
|
|
with patch.object(self.compose_mod.shutil, "which", fake_which):
|
|
calls = []
|
|
|
|
def fake_run(cmd, check: bool):
|
|
calls.append((cmd, check))
|
|
return 0
|
|
|
|
with patch.object(self.compose_mod.subprocess, "run", fake_run):
|
|
self.compose_mod.hard_restart_docker_services(str(d))
|
|
|
|
self.assertEqual(
|
|
calls,
|
|
[
|
|
(
|
|
[
|
|
"/usr/local/bin/compose",
|
|
"--chdir",
|
|
str(d.resolve()),
|
|
"--",
|
|
"down",
|
|
],
|
|
True,
|
|
),
|
|
(
|
|
[
|
|
"/usr/local/bin/compose",
|
|
"--chdir",
|
|
str(d.resolve()),
|
|
"--",
|
|
"up",
|
|
"-d",
|
|
],
|
|
True,
|
|
),
|
|
],
|
|
)
|
|
|
|
def test_hard_restart_calls_run_twice_with_correct_cmds_fallback(self) -> None:
|
|
with tempfile.TemporaryDirectory() as td:
|
|
tmp_path = Path(td)
|
|
d = _setup_compose_dir(
|
|
tmp_path,
|
|
name="mailu",
|
|
with_override=True,
|
|
with_ca_override=True,
|
|
env_layout=".env/env",
|
|
)
|
|
|
|
def fake_which(name: str):
|
|
if name == "compose":
|
|
return None
|
|
if name == "docker":
|
|
return "/usr/bin/docker"
|
|
return None
|
|
|
|
with patch.object(self.compose_mod.shutil, "which", fake_which):
|
|
calls = []
|
|
|
|
def fake_run(cmd, check: bool):
|
|
calls.append((cmd, check))
|
|
return 0
|
|
|
|
with patch.object(self.compose_mod.subprocess, "run", fake_run):
|
|
self.compose_mod.hard_restart_docker_services(str(d))
|
|
|
|
self.assertEqual(
|
|
calls,
|
|
[
|
|
(
|
|
[
|
|
"/usr/bin/docker",
|
|
"compose",
|
|
"--chdir",
|
|
str(d.resolve()),
|
|
"down",
|
|
],
|
|
True,
|
|
),
|
|
(
|
|
[
|
|
"/usr/bin/docker",
|
|
"compose",
|
|
"--chdir",
|
|
str(d.resolve()),
|
|
"up",
|
|
"-d",
|
|
],
|
|
True,
|
|
),
|
|
],
|
|
)
|