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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
import { actionCreators as ac, actionTypes as at } from "common/Actions.mjs";
import { perfService as perfSvc } from "content-src/lib/perf-service";
import React from "react";
// Currently record only a fixed set of sections. This will prevent data
// from custom sections from showing up or from topstories.
const RECORDED_SECTIONS = ["highlights", "topsites"];
export class ComponentPerfTimer extends React.Component {
constructor(props) {
super(props);
// Just for test dependency injection:
this.perfSvc = this.props.perfSvc || perfSvc;
this._sendBadStateEvent = this._sendBadStateEvent.bind(this);
this._sendPaintedEvent = this._sendPaintedEvent.bind(this);
this._reportMissingData = false;
this._timestampHandled = false;
this._recordedFirstRender = false;
}
componentDidMount() {
if (!RECORDED_SECTIONS.includes(this.props.id)) {
return;
}
this._maybeSendPaintedEvent();
}
componentDidUpdate() {
if (!RECORDED_SECTIONS.includes(this.props.id)) {
return;
}
this._maybeSendPaintedEvent();
}
/**
* Call the given callback after the upcoming frame paints.
*
* @note Both setTimeout and requestAnimationFrame are throttled when the page
* is hidden, so this callback may get called up to a second or so after the
* requestAnimationFrame "paint" for hidden tabs.
*
* Newtabs hidden while loading will presumably be fairly rare (other than
* preloaded tabs, which we will be filtering out on the server side), so such
* cases should get lost in the noise.
*
* If we decide that it's important to find out when something that's hidden
* has "painted", however, another option is to post a message to this window.
* That should happen even faster than setTimeout, and, at least as of this
* writing, it's not throttled in hidden windows in Firefox.
*
* @param {Function} callback
*
* @returns void
*/
_afterFramePaint(callback) {
requestAnimationFrame(() => setTimeout(callback, 0));
}
_maybeSendBadStateEvent() {
// Follow up bugs:
if (!this.props.initialized) {
// Remember to report back when data is available.
this._reportMissingData = true;
} else if (this._reportMissingData) {
this._reportMissingData = false;
// Report how long it took for component to become initialized.
this._sendBadStateEvent();
}
}
_maybeSendPaintedEvent() {
// If we've already handled a timestamp, don't do it again.
if (this._timestampHandled || !this.props.initialized) {
return;
}
// And if we haven't, we're doing so now, so remember that. Even if
// something goes wrong in the callback, we can't try again, as we'd be
// sending back the wrong data, and we have to do it here, so that other
// calls to this method while waiting for the next frame won't also try to
// handle it.
this._timestampHandled = true;
this._afterFramePaint(this._sendPaintedEvent);
}
/**
* Triggered by call to render. Only first call goes through due to
* `_recordedFirstRender`.
*/
_ensureFirstRenderTsRecorded() {
// Used as t0 for recording how long component took to initialize.
if (!this._recordedFirstRender) {
this._recordedFirstRender = true;
// topsites_first_render_ts, highlights_first_render_ts.
const key = `${this.props.id}_first_render_ts`;
this.perfSvc.mark(key);
}
}
/**
* Creates `SAVE_SESSION_PERF_DATA` with timestamp in ms
* of how much longer the data took to be ready for display than it would
* have been the ideal case.
*/
_sendBadStateEvent() {
// highlights_data_ready_ts, topsites_data_ready_ts.
const dataReadyKey = `${this.props.id}_data_ready_ts`;
this.perfSvc.mark(dataReadyKey);
try {
const firstRenderKey = `${this.props.id}_first_render_ts`;
// value has to be Int32.
const value = parseInt(
this.perfSvc.getMostRecentAbsMarkStartByName(dataReadyKey) -
this.perfSvc.getMostRecentAbsMarkStartByName(firstRenderKey),
10
);
this.props.dispatch(
ac.OnlyToMain({
type: at.SAVE_SESSION_PERF_DATA,
// highlights_data_late_by_ms, topsites_data_late_by_ms.
data: { [`${this.props.id}_data_late_by_ms`]: value },
})
);
} catch (ex) {
// If this failed, it's likely because the `privacy.resistFingerprinting`
// pref is true.
}
}
_sendPaintedEvent() {
// Record first_painted event but only send if topsites.
if (this.props.id !== "topsites") {
return;
}
// topsites_first_painted_ts.
const key = `${this.props.id}_first_painted_ts`;
this.perfSvc.mark(key);
try {
const data = {};
data[key] = this.perfSvc.getMostRecentAbsMarkStartByName(key);
this.props.dispatch(
ac.OnlyToMain({
type: at.SAVE_SESSION_PERF_DATA,
data,
})
);
} catch (ex) {
// If this failed, it's likely because the `privacy.resistFingerprinting`
// pref is true. We should at least not blow up, and should continue
// to set this._timestampHandled to avoid going through this again.
}
}
render() {
if (RECORDED_SECTIONS.includes(this.props.id)) {
this._ensureFirstRenderTsRecorded();
this._maybeSendBadStateEvent();
}
return this.props.children;
}
}