api/common_api.php

   1 <?php
   2 include "../common.php";
   3
   4 if(session_status() !== PHP_SESSION_ACTIVE) session_start();
   5
   6 if (!isset($_SESSION['id']))
   7         die("Access denied");
   8
   9 // Close the session now, otherwise other pages block
  10 session_write_close();
  11
  12 // Only now make the connection (this can take a short while)
  13 include "../connection.php";
  14
  15 // Server Side Events
  16 header('Content-Type: text/event-stream');
  17
  18 // Explicitly disable caching so Varnish and other upstreams won't cache.
  19 header("Cache-Control: no-cache, must-revalidate");
  20
  21 // Setting this header instructs Nginx to disable fastcgi_buffering and disable
  22 // gzip for this request.
  23 header('X-Accel-Buffering: no');
  24
  25 // No time limit
  26 set_time_limit(0);
  27
  28 // Send content immediately
  29 ob_implicit_flush(1);
  30
  31 // Eh.. yeah...
  32 ob_end_flush();
  33
  34 // If we use fastcgi, then finish the request now (UNTESTED)
  35 if (function_exists('fastcgi_finish_request'))
  36         fastcgi_finish_request();
  37
  38 /* Send server-sent events (SSE) message */
  39 function send_sse($json)
  40 {
  41         echo "data: ".json_encode($json)."\n\n";
  42 }
  43
  44 function api_log_loop($sources)
  45 {
  46         GLOBAL $rpc;
  47
  48         $rpc->log()->subscribe($sources);
  49         if ($rpc->error)
  50         {
  51                 echo $rpc->error;
  52                 die;
  53         }
  54
  55         for(;;)
  56         {
  57                 $res = $rpc->eventloop();
  58                 if (!$res)
  59                 {
  60                         /* Output at least something every timeout (10) seconds,
  61                          * otherwise PHP may not
  62                          * notice when the webclient is gone.
  63                          */
  64                         echo "\n";
  65                         continue;
  66                 }
  67                 send_sse($res);
  68         }
  69 }
  70
  71 function api_timer_loop(int $every_msec, string $method, array|null $params = null)
  72 {
  73         GLOBAL $rpc;
  74
  75         $rpc->rpc()->add_timer("timer", $every_msec, $method, $params);
  76         if ($rpc->error)
  77         {
  78                 /* Have to resort to old style: client-side timer */
  79                 while(1)
  80                 {
  81                         $res = $rpc->query($method, $params);
  82                         if (!$res)
  83                                 die;
  84                         send_sse($res);
  85                         usleep($every_msec * 1000);
  86                 }
  87         }
  88
  89         /* New style: use server-side timers */
  90         for(;;)
  91         {
  92                 $res = $rpc->eventloop();
  93                 if (!$res)
  94                 {
  95                         /* Output at least something every timeout (10) seconds,
  96                          * otherwise PHP may not
  97                          * notice when the webclient is gone.
  98                          */
  99                         echo "\n";
 100                         continue;
 101                 }
 102                 send_sse($res);
 103         }
 104 }