ReportingObserver

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The ReportingObserver interface of the Reporting API allows you to collect and access reports.

Constructor

ReportingObserver()

Creates a new ReportingObserver object instance, which can be used to collect and access reports.

Properties

This interface has no properties defined on it.

Methods

ReportingObserver.disconnect()

Stops a reporting observer that had previously started observing from collecting reports.

ReportingObserver.observe()

Instructs a reporting observer to start collecting reports in its report queue.

ReportingObserver.takeRecords()

Returns the current list of reports contained in the observer's report queue, and empties the queue.

Events

This interface has no events that fire on it.

Examples

In our deprecation_report.html example, we create a simple reporting observer to observe usage of deprecated features on our web page:

let options = {
  types: ['deprecation'],
  buffered: true
}

let observer = new ReportingObserver(function(reports, observer) {
  reportBtn.onclick = () => displayReports(reports);
}, options);

We then tell it to start observing reports using ReportingObserver.observe(); this tells the observer to start collecting reports in its report queue, and runs the callback function specified inside the constructor:

observer.observe();

Later on in the example we deliberately use the deprecated version of MediaDevices.getUserMedia():

if(navigator.mozGetUserMedia) {
  navigator.mozGetUserMedia(
    constraints,
    success,
    failure);
} else {
  navigator.getUserMedia(
    constraints,
    success,
    failure);
}

This causes a deprecation report to be generated; because of the event handler we set up inside the ReportingObserver() constructor, we can now click the button to display the report details.

image of a jolly bearded man with various stats displayed below it about a deprecated feature

Note: If you look at the complete source code, you'll notice that we actually call the deprecated getUserMedia() method twice. After the first time we call ReportingObserver.takeRecords(), which returns the first generated report and empties the queue. Because of this, when the button is pressed only the second report is listed.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
ReportingObserver
69
79
No
No
56
No
69
69
No
48
No
10.0
ReportingObserver
69
79
No
No
56
No
69
69
No
48
No
10.0
disconnect
69
79
No
No
56
No
69
69
No
48
No
10.0
observe
69
79
No
No
56
No
69
69
No
48
No
10.0
takeRecords
69
79
No
No
56
No
69
69
No
48
No
10.0
worker_support
84
84
No
No
70
No
84
84
No
No
No
14.0

See also

© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/ReportingObserver