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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, You can obtain one at http://mozilla.org/MPL/2.0/. */
export function UrlClassifierExceptionListService() {}
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
});
const COLLECTION_NAME = "url-classifier-skip-urls";
class Feature {
constructor(name, prefName) {
this.name = name;
this.prefName = prefName;
this.observers = new Set();
this.prefValue = null;
this.remoteEntries = null;
if (prefName) {
this.prefValue = Services.prefs.getStringPref(this.prefName, null);
Services.prefs.addObserver(prefName, this);
}
}
async addAndRunObserver(observer) {
this.observers.add(observer);
this.notifyObservers(observer);
}
removeObserver(observer) {
this.observers.delete(observer);
}
observe(subject, topic, data) {
if (topic != "nsPref:changed" || data != this.prefName) {
console.error(`Unexpected event ${topic} with ${data}`);
return;
}
this.prefValue = Services.prefs.getStringPref(this.prefName, null);
this.notifyObservers();
}
onRemoteSettingsUpdate(entries) {
this.remoteEntries = [];
for (let entry of entries) {
if (entry.feature == this.name) {
this.remoteEntries.push(entry.pattern.toLowerCase());
}
}
}
notifyObservers(observer = null) {
let entries = [];
if (this.prefValue) {
entries = this.prefValue.split(",");
}
if (this.remoteEntries) {
for (let entry of this.remoteEntries) {
entries.push(entry);
}
}
let entriesAsString = entries.join(",").toLowerCase();
if (observer) {
observer.onExceptionListUpdate(entriesAsString);
} else {
for (let obs of this.observers) {
obs.onExceptionListUpdate(entriesAsString);
}
}
}
}
UrlClassifierExceptionListService.prototype = {
classID: Components.ID("{b9f4fd03-9d87-4bfd-9958-85a821750ddc}"),
QueryInterface: ChromeUtils.generateQI([
"nsIUrlClassifierExceptionListService",
]),
features: {},
_initialized: false,
async lazyInit() {
if (this._initialized) {
return;
}
let rs = lazy.RemoteSettings(COLLECTION_NAME);
rs.on("sync", event => {
let {
data: { current },
} = event;
this.entries = current || [];
this.onUpdateEntries(current);
});
this._initialized = true;
// If the remote settings list hasn't been populated yet we have to make sure
// to do it before firing the first notification.
// This has to be run after _initialized is set because we'll be
// blocked while getting entries from RemoteSetting, and we don't want
// LazyInit is executed again.
try {
// The data will be initially available from the local DB (via a
// resource:// URI).
this.entries = await rs.get();
} catch (e) {}
// RemoteSettings.get() could return null, ensure passing a list to
// onUpdateEntries.
if (!this.entries) {
this.entries = [];
}
this.onUpdateEntries(this.entries);
},
onUpdateEntries(entries) {
for (let key of Object.keys(this.features)) {
let feature = this.features[key];
feature.onRemoteSettingsUpdate(entries);
feature.notifyObservers();
}
},
registerAndRunExceptionListObserver(feature, prefName, observer) {
// We don't await this; the caller is C++ and won't await this function,
// and because we prevent re-entering into this method, once it's been
// called once any subsequent calls will early-return anyway - so
// awaiting that would be meaningless. Instead, `Feature` implementations
// make sure not to call into observers until they have data, and we
// make sure to let feature instances know whether we have data
// immediately.
this.lazyInit();
if (!this.features[feature]) {
let featureObj = new Feature(feature, prefName);
this.features[feature] = featureObj;
// If we've previously initialized, we need to pass the entries
// we already have to the new feature.
if (this.entries) {
featureObj.onRemoteSettingsUpdate(this.entries);
}
}
this.features[feature].addAndRunObserver(observer);
},
unregisterExceptionListObserver(feature, observer) {
if (!this.features[feature]) {
return;
}
this.features[feature].removeObserver(observer);
},
clear() {
this.features = {};
this._initialized = false;
this.entries = null;
},
};