Queueing events when sessions response is slow

The Media Collection API is RESTful: i.e, you make an HTTP request and wait for the response. This is an important point only for when you make a Sessions request to obtain a Session ID at the beginning of video playback. This is important because the Session ID is required for all subsequent tracking calls.

It is possible that your player may fire events before the Sessions response returns (with the Session ID parameter) from the backend. If this occurs, your app must queue any tracking events that arrive between the Sessions request and its response. When the Sessions response arrives, you should first process any queued events, then you can start processing live events with the Events calls.


The Events request does not return data back to the client beyond an HTTP response code.

Check the Reference Player in your distribution for one way to process events prior to receiving a Session ID. For example:

var eventData = {};            // JSON payload 
eventData.playerTime = getPlayerTime(); // Required 
eventData.eventType = "play";           // Required 
eventData.params = {};                  // Optional for events 
VideoPlayer.prototype._collectEvent =  
  function(eventData) { 
    // If we don't have a Session ID yet,  
    // queue the event and return... 
    if (!sessionStarted) { 
        console.log("[Player] Queueing event "); 
    // If we DO have a Session ID, process the 
    // tracking event...     
        "baseUrl": "{endpoint}", 
        "path": "api/v1/{sid}/events", // events request 
        "method": "POST", 
        "data": eventData 
    }).then((response) => {   
VideoPlayer.prototype.collectEvent =  
  function (eventType, eventParams) { 
    if (typeof eventParams === 'undefined') {   
        eventParams = {}; 
        eventType: eventType,            // Required 
        playerTime: getPlayerTime(),     // Required 
        params: eventParams              // Optional  
VideoPlayer.prototype.getPlayerTime = function() { 
    return { 
        playhead: this.getPlayhead(),    // playhead value in seconds 
        ts: this.getCurrentTimestamp()   // timestamp value in milliseconds 

Process any queued events - The reference player processes queued events as follows:

    this._processPendingEvents();    // Once you have a Session ID, 
    […]                              // process any queued events 
VideoPlayer.prototype._processPendingEvents =  
  function() { 
    this._pendingEvents.forEach((eventData) => { 
    this._pendingEvents = []; 

Continue to process tracking events as they occur.

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