Closing connection during a long running query blocks the loop

[Oleg Kolesov]

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.

[Oleg Kolesov]

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

[Aaron Piotrowski]

#54 has been merged and tagged under v1.4.5.