ReportingObserver: ReportingObserver() constructor

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Note: This feature is available in Web Workers.

The ReportingObserver() constructor of the Reporting API creates a new ReportingObserver object instance, which can be used to collect and access reports.

Syntax

new ReportingObserver(callback)
new ReportingObserver(callback, options)

Parameters

callback

A callback function that runs when the observer starts to collect reports (i.e., via ReportingObserver.observe()). The callback function is given two parameters:

reports: A sequence of Report objects representing the reports collected in the observer's report queue. This is probably the most common way to retrieve the reports.
observer: A reference to the same ReportingObserver object, allowing for recursive report collection, etc.

options Optional

An object allowing you to set the options for creating the object. The available options are:

types: An array of strings representing the types of report to be collected by this observer. Available types include deprecation, intervention, and crash (although this last type usually isn't retrievable via a ReportingObserver). If this option is omitted, all supported types are collected.
buffered: a boolean that defines whether the reports that were generated before the observer was able to be created should be observable (true) or not (false).

Examples

const options = {
  types: ["deprecation"],
  buffered: true,
};

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