amphp
Closing connection during a long running query blocks the loop
If we have a long running query and try to close connection while it is executing, loop will be blocked.
Script:
<?php
use Amp\Loop;
use Amp\Postgres\ConnectionConfig;
use function Amp\Postgres\pool;
require __DIR__ . '/../vendor/autoload.php';
Loop::run(function () {
echo 'Start' . PHP_EOL;
$config = ConnectionConfig::fromString("host=localhost user=test password=1234 db=test");
$pool = pool($config);
Loop::repeat(1000, static function () {
echo 'Loop heartbeat: ' . time() . PHP_EOL;
});
Loop::delay(3000, static function () use ($pool) {
echo 'Close connection' . PHP_EOL;
$pool->close();
});
try {
echo 'Query' . PHP_EOL;
$result = yield $pool->execute('SELECT pg_sleep(10)');
while (yield $result->advance()) {
$row = $result->getCurrent();
var_dump($row);
}
} catch (Throwable $e) {
echo $e->getMessage() . PHP_EOL;
}
});
Result:
Start Query Loop heartbeat: 1661195555 Loop heartbeat: 1661195556 Close connection The connection was closed Loop heartbeat: 1661195564 Loop heartbeat: 1661195565 Loop heartbeat: 1661195566 Loop heartbeat: 1661195567
Loop was blocking for 8 seconds from 1661195556 to 1661195564 until query end. Is it expected behavoir?
Seems, loop must not be blocked in this case.
Try to cancel query before pg_close() in src/PgSqlHandle.php::close().
Start Query Loop heartbeat: 1661196633 Loop heartbeat: 1661196634 Close connection The connection was closed Loop heartbeat: 1661196635 Loop heartbeat: 1661196636 Loop heartbeat: 1661196637 Loop heartbeat: 1661196638
