api/common_api.php

   1 <?php
   2 include "../inc/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 "../inc/connection.php";
  14
  15 // Server Side Events
  16 if (!defined('NO_EVENT_STREAM_HEADER'))
  17         header('Content-Type: text/event-stream');
  18
  19 // Explicitly disable caching so Varnish and other upstreams won't cache.
  20 header("Cache-Control: no-cache, must-revalidate");
  21
  22 // Setting this header instructs Nginx to disable fastcgi_buffering and disable
  23 // gzip for this request.
  24 header('X-Accel-Buffering: no');
  25
  26 // No time limit
  27 set_time_limit(0);
  28
  29 // Send content immediately
  30 ob_implicit_flush(1);
  31
  32 // Flush and stop output buffering (eg fastcgi w/NGINX)
  33 while (1)
  34 {
  35         try {
  36                 $ret = @ob_end_flush();
  37                 if ($ret === false)
  38                         break;
  39         } catch(Exception $e)
  40         {
  41                 break;
  42         }
  43 };
  44
  45 /* Send server-sent events (SSE) message */
  46 function send_sse($json)
  47 {
  48         echo "data: ".json_encode($json)."\n\n";
  49 }
  50
  51 function api_log_loop($sources)
  52 {
  53         GLOBAL $rpc;
  54
  55         $rpc->log()->subscribe($sources);
  56         if ($rpc->error)
  57         {
  58                 echo $rpc->error;
  59                 die;
  60         }
  61
  62         for(;;)
  63         {
  64                 $res = $rpc->eventloop();
  65                 if (!$res)
  66                 {
  67                         /* Output at least something every timeout (10) seconds,
  68                          * otherwise PHP may not
  69                          * notice when the webclient is gone.
  70                          */
  71                         echo "\n";
  72                         continue;
  73                 }
  74                 send_sse($res);
  75         }
  76 }
  77
  78 function api_timer_loop(int $every_msec, string $method, array|null $params = null)
  79 {
  80         GLOBAL $rpc;
  81
  82         $rpc->rpc()->add_timer("timer", $every_msec, $method, $params);
  83         if ($rpc->error)
  84         {
  85                 /* Have to resort to old style: client-side timer */
  86                 while(1)
  87                 {
  88                         $res = $rpc->query($method, $params);
  89                         if (!$res)
  90                                 die;
  91                         send_sse($res);
  92                         usleep($every_msec * 1000);
  93                 }
  94         }
  95
  96         /* New style: use server-side timers */
  97         for(;;)
  98         {
  99                 $res = $rpc->eventloop();
 100                 if (!$res)
 101                 {
 102                         /* Output at least something every timeout (10) seconds,
 103                          * otherwise PHP may not
 104                          * notice when the webclient is gone.
 105                          */
 106                         echo "\n";
 107                         continue;
 108                 }
 109                 send_sse($res);
 110         }
 111 }