How to connect to mysql async in worker_init ?

[joanhey]

I am trying that:

<?php
//app_async.php called from init_worker_by_php
require_once '/ngx_php7/t/lib/mysql.php';

define('DB_HOST', gethostbyname('tfb-database'));
define('DB_PORT', '3306');
define('DB_USER', 'benchmarkdbuser');
define('DB_PASS', 'benchmarkdbpass');
define('DB_NAME', 'hello_world');

$my = new php\ngx\mysql();
yield from $my->connect(DB_HOST, DB_PORT, DB_USER, DB_PASS, DB_NAME);

function db()
{
    ngx_header_set('Content-Type', 'application/json');

    global $my;

    echo json_encode(
        (yield from $my->query('SELECT id,randomNumber FROM World WHERE id = '.mt_rand(1, 10000)))[0]
    );

}

And get this error:

php-ngx-async: 2019/11/04 13:50:35 [error] 9#0: *1 Fatal error: Uncaught Error: Call to undefined function db() in ngx_php eval code:2
php-ngx-async: Stack trace:
php-ngx-async: #0 [internal function]: ngx_content_50c025ec7080d0b5458512d034e7a3bb()
php-ngx-async: #1 [internal function]: Generator->valid()
php-ngx-async: #2 {main}
php-ngx-async:   thrown in ngx_php eval code on line 2, client: 172.18.0.5, server: , request: "GET /db HTTP/1.1", host: "tfb-server:8080"
php-ngx-async: 2019/11/04 13:50:35 [error] 9#0: *1 ngx_php ctx is nil at content inline handler. while keepalive, client: 172.18.0.5, server: 0.0.0.0:8080

[rryqszq4]

@joanhey This is because app_async.php reports an error in the init_worker_by_php phase, causing the db function to not parse normally. Currently, the init_worker_by_php phase cannot use asynchronous interfaces.

[rryqszq4]

In init_worker_by_php phase can not output error log, and need to fix~

[joanhey]

The important think is to have async queries. The connection in most cases don't need to be async, but better if it is also posible to use in some cases.