Files
nextcloud-ng_backup/spikes/06-resumable.php
dillard 7b33347dbc Phase 0: fixes from review (torn files, pending blobs, exact sequences, UTF-8, storage checks)
- detect files changing during reading or between resumable steps and
  re-read them (size/mtime/ctime/inode), spike F overwrites mid-run
- drop pending blob ids when a pack or index upload fails
- dump and restore PostgreSQL sequence state exactly, bound parameters,
  validated catalog names; spike C checks all sequences exactly
- keep invalid UTF-8 byte-exact (tagged base64)
- refuse large tables without a primary key
- StorageBackend: check write/flush/close results, validate base path
- user_migration import/export: root paths, intermediate folders,
  partial writes, read errors
- spikes: never touch an existing account, own fixtures, 512M note
2026-10-01 18:58:51 +02:00

94 lines
3.5 KiB
PHP

<?php
declare(strict_types=1);
// Spike F: resumable, time-boxed backup steps in separate processes, surviving kill -9.
// php 06-resumable.php prepare <work>
// php 06-resumable.php step <work> <seconds> (repeat until it prints "done")
// php 06-resumable.php verify <work>
require __DIR__ . '/bootstrap.php';
use OCA\NgBackup\Backend\LocalBackend;
use OCA\NgBackup\Job\BackupRun;
use OCA\NgBackup\Repository\Repository;
[$_, $mode, $work] = $argv + [null, null, '/tmp/ngb-f'];
$src = "$work/src";
$stateFile = "$work/state.json";
$pass = 'spike passphrase';
$hashTree = static function (string $root): array {
$out = [];
$it = new RecursiveIteratorIterator(new RecursiveDirectoryIterator($root, FilesystemIterator::SKIP_DOTS));
foreach ($it as $f) {
if ($f->isFile()) {
$out[substr($f->getPathname(), strlen($root) + 1)] = hash_file('sha256', $f->getPathname());
}
}
ksort($out);
return $out;
};
switch ($mode) {
case 'prepare':
exec('rm -rf ' . escapeshellarg($work));
mkdir("$src/docs", 0700, true);
for ($i = 0; $i < 400; $i++) {
file_put_contents(sprintf('%s/docs/n%03d.txt', $src, $i), random_bytes(30000) . str_repeat('x', 30000));
}
$fh = fopen("$src/huge.bin", 'wb');
for ($i = 0; $i < 200; $i++) {
fwrite($fh, random_bytes(1048576));
}
fclose($fh);
Repository::init(new LocalBackend("$work/repo"), $pass);
file_put_contents("$work/expected.json", json_encode($hashTree($src)));
file_put_contents($stateFile, json_encode(BackupRun::start($src, null, 'resumable')));
echo "prepared\n";
break;
case 'step':
$seconds = (float)($argv[3] ?? 1.5);
$state = json_decode(file_get_contents($stateFile), true);
if ($state['phase'] === 'done') {
echo "done\n";
break;
}
$repo = Repository::open(new LocalBackend("$work/repo"), $pass);
$t = microtime(true);
$state = BackupRun::step($repo, $state, $t + $seconds);
// Simulate a user overwriting the big file (same size) while the run is in the middle of it.
if (getenv('NGB_MUTATE') === '1' && ($state['cur']['path'] ?? '') === 'huge.bin' && !file_exists("$work/mutated")) {
$fh = fopen("$src/huge.bin", 'r+b');
fseek($fh, 10 * 1048576);
fwrite($fh, random_bytes(1048576));
fclose($fh);
touch("$src/huge.bin", time() + 5);
file_put_contents("$work/expected.json", json_encode($hashTree($src)));
touch("$work/mutated");
echo " -> huge.bin overwritten (same size) between steps\n";
}
// Save the state atomically: a kill before this point means the step is simply redone.
file_put_contents("$stateFile.tmp", json_encode($state));
rename("$stateFile.tmp", $stateFile);
printf("step %d: %.1fs, phase %s, file %d/%d%s, peak %.0f MiB\n", $state['steps'], microtime(true) - $t, $state['phase'],
$state['pos'], max(count($state['files']), $state['pos']),
$state['cur'] ? sprintf(' (in %s at %d MiB)', $state['cur']['path'], $state['cur']['offset'] / 1048576) : '',
memory_get_peak_usage() / 1048576);
if ($state['phase'] === 'done') {
echo 'done ' . json_encode($state['stats']) . "\n";
}
break;
case 'verify':
$state = json_decode(file_get_contents($stateFile), true);
$repo = Repository::open(new LocalBackend("$work/repo"), $pass);
exec('rm -rf ' . escapeshellarg("$work/restore"));
$repo->restore($state['snapshot'], "$work/restore");
$same = $hashTree("$work/restore") === json_decode(file_get_contents("$work/expected.json"), true);
printf("%-60s %s\n", 'restored tree identical after resumable run with kills', $same ? 'PASS' : 'FAIL');
exec('rm -rf ' . escapeshellarg($work));
exit($same ? 0 : 1);
}