How do nginx-push-stream-module and php interact?

Question

PHP

I'm trying to figure out the technology of long polling according to the article https://habr.com/ru/post/252349/ .
Nginx rebuilt with the module, here

nginx.conf listing

user  www-data;
worker_processes  1;
events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;
    sendfile        on;
    keepalive_timeout  65;

    server {
        listen 80;
        charset utf-8;
        root /var/www;
        index  index.php;

                                                                                                            
        location ~ \.php$ {                                                                                 
             include fastcgi_params;                                                                         
             fastcgi_pass  unix:/var/run/php5-fpm.sock;                                                      
             fastcgi_index index.php;                                                                        
             fastcgi_param  SCRIPT_FILENAME  $document_root$fastcgi_script_name;                             
        }                                                                                                   

        location /pub {
            push_stream_publisher          admin;
            set $push_stream_channel_id    $arg_id;
            push_stream_store_messages     on;
            allow                          127.0.0.1;
        }

        location ~ /sub/(.*) {
            push_stream_subscriber                  long-polling;
            push_stream_last_received_message_tag   $arg_tag;
            push_stream_last_received_message_time  $arg_time;
            push_stream_longpolling_connection_ttl  25s;
             push_stream_channels_path    $1;
       }
    }
    push_stream_shared_memory_size       32M;
    push_stream_channels_path             $1;
}

Next, cURL sends messages:

listing

<?php
  //$channel_id = 1;
  $message = 'Привет!';
  //отправка сообщения
  $ch = curl_init();
  curl_setopt($ch, CURLOPT_URL, 'localhost/pub/1');
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
  curl_setopt($ch, CURLOPT_POST, true);
  curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($message));
  curl_exec($ch);
  print_r(curl_getinfo($ch));
  curl_close($ch);

There is a recipient:

listing

//let channelId = 1; //id подписчика
  let last_etag = 0; //переменная для заголовка 'Etag'
  let last_time = null; //переменная для заголовка 'Last-Modified'

  function new_message() {
    $.ajax({
      url: '/sub/1',
      type: "GET",
      dataType: 'json',
      beforeSend: function (xhr) {
        xhr.setRequestHeader('Etag', last_etag);
        xhr.setRequestHeader('Last-Modified', last_time);
      },
      success: function (data, status, xhr) {
        last_etag = xhr.getResponseHeader('Etag'); //присваиваем новое значение переменной last_etag
                                                     // из заголовка 'Etag' ответа
        last_time = xhr.getResponseHeader('Last-Modified'); // присваиваем новое значение переменной last_time
                                                              // из заголовка 'Last-Modified' ответа

        //здесь что-то делаем с полученным сообщением
        console.log(data)
        console.log(status)
        //console.log(xhr)

        setTimeout(new_message, 500);	 // переподключаемся сразу после получения ответа
      }
    })
  }

  new_message();

Long polling seems to work, because the output of data and status to the console occurs every 25 seconds (taking into account the push_stream_longpolling_connection_ttl directive)
But it is not at all clear how it should work. The message was posted to the server, but where? he must be preserved. The subscriber checks the messages, but how to notify him and who will generate the json on the server with the message and status?? Help me to understand.

Answer 1

I recommend using the PushStream lib on the frontend JS https://github.com/wandenberg/nginx-push-stream-mo...
Sending a message to the frontend via the nginx-push-stream-module server

$message = array('message'=>'Привет!');
    $idChannel = 1; //ID канала
    $nginxPushStreamModuleHost = 'http://localhost/'  //ВАШ СЕРВЕР С nginx-push-stream-module
      //отправка сообщения
      $ch = curl_init();
      curl_setopt($ch, CURLOPT_URL, $nginxPushStreamModuleHost.'pub/'.$idChannel);
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
      curl_setopt($ch, CURLOPT_POST, true);
      curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($message));
      curl_exec($ch);
      print_r(curl_getinfo($ch));
      curl_close($ch);

Listening to the nginx-push-stream-module server on the frontend

idChannel = 1; //ID канала
nginxPushStreamModuleHost = 'http://localhost/'; //ВАШ СЕРВЕР С nginx-push-stream-module

pushstream = new PushStream({
                        timeout: 20000,
                        modes: 'eventsource|stream',
                        host:nginxPushStreamModuleHost,
                    
                        useSSL:false 
                        
                      });

pushstream.onmessage = function(json) {
//Сработает если с сервера что-то пришло пользователю
alert('О! что-то пришол! Сообщение: '+json.message)
}

pushstream.addChannel(idChannel);
pushstream.connect();