subscribe not working

[pheelaphong]

---

$mqtt = MQTT::connection();
$mqtt->subscribe('stat/xxxxxxxx/POWER', function (string $topic, string $message) {
        return response()->json(['topic' => $topic, 'message' => $message], 200);
}, 0);

return empty

---

But on MQTT Dashboard (App android) this topic working
And publish working

[Namoshek]

Before I tell you what's wrong, let me tell you that what you are trying to do, doesn't make much sense. Waiting within a request on a published message will block the request. It can be done, but it is a bad idea.

To focus on the problem: you are returning a response from the subscription callback, which is discarded (the MqttClient expects no return value from the closure). You also have not called $mqtt->loop(), which is required for a subscription. A working example would be:

$result = [];

$mqtt = MQTT::connection();
$mqtt->subscribe('stat/xxxxxxxx/POWER', function (string $topic, string $message) use ($mqtt, &$result) {
    $result['topic'] = $topic;
    $result['message'] = $message;

    $mqtt->interrupt();
}, 0);
$mqtt->loop(true);

return response()->json($result, 200);

---

But I repeat myself: this makes no sense. You should not be waiting for published messages in a request. Most php-fpm deployments are configured with a fixed number of workers, which means the whole application will already be unreachable after 10 concurrent requests or so. If you need to process incoming data, use a console command for it.

[pheelaphong]

Before I tell you what's wrong, let me tell you that what you are trying to do, doesn't make much sense. Waiting within a request on a published message will block the request. It can be done, but it is a bad idea.

To focus on the problem: you are returning a response from the subscription callback, which is discarded (the MqttClient expects no return value from the closure). You also have not called $mqtt->loop(), which is required for a subscription. A working example would be:

$result = [];

$mqtt = MQTT::connection();
$mqtt->subscribe('stat/xxxxxxxx/POWER', function (string $topic, string $message) use ($mqtt, &$result) {
    $result['topic'] = $topic;
    $result['message'] = $message;

    $mqtt->interrupt();
}, 0);
$mqtt->loop(true);

return response()->json($result, 200);

But I repeat myself: this makes no sense. You should not be waiting for published messages in a request. Most php-fpm deployments are configured with a fixed number of workers, which means the whole application will already be unreachable after 10 concurrent requests or so. If you need to process incoming data, use a console command for it.

Working, Thank you for your advice.