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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
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
NetworkObserver:
});
/**
* The NetworkThrottler uses the dev tools NetworkObserver to provide api to throttle all network activity.
* This can be used to fix network conditions in browsertime pageload tests.
*
*/
// A minimal struct for onNetworkEvent handling
class NetworkEventRecord {
addRequestPostData() {}
addResponseStart() {}
addSecurityInfo() {}
addEventTimings() {}
addResponseCache() {}
addResponseContent() {}
addServerTimings() {}
addServiceWorkerTimings() {}
}
class NetworkThrottler {
#devtoolsNetworkObserver;
#throttling;
constructor() {
this.#throttling = false;
}
destroy() {
this.stop();
}
start(throttleData) {
if (this.#throttling) {
console.error("NetworkThrottler already started");
return;
}
this.#devtoolsNetworkObserver = new lazy.NetworkObserver({
ignoreChannelFunction: this.#ignoreChannelFunction,
onNetworkEvent: this.#onNetworkEvent,
});
this.#devtoolsNetworkObserver.setThrottleData(throttleData);
this.#throttling = true;
}
stop() {
if (!this.#throttling) {
return;
}
this.#devtoolsNetworkObserver.destroy();
this.#devtoolsNetworkObserver = null;
this.#throttling = false;
}
#ignoreChannelFunction = channel => {
// Ignore chrome-privileged or DevTools-initiated requests
if (
channel.loadInfo?.loadingDocument === null &&
(channel.loadInfo.loadingPrincipal ===
Services.scriptSecurityManager.getSystemPrincipal() ||
channel.loadInfo.isInDevToolsContext)
) {
return true;
}
return false;
};
#onNetworkEvent = (networkEvent, channel) => {
return new NetworkEventRecord(networkEvent, channel, this);
};
}