feat: add OptionsProvider
This class will replace the current PartialOptionsWatcher.
Change-Id: I09e5847e6d9d94362683629f5576e804eef20955
diff --git a/src/common/OptionsProvider.ts b/src/common/OptionsProvider.ts
new file mode 100644
index 0000000..36370a1
--- /dev/null
+++ b/src/common/OptionsProvider.ts
@@ -0,0 +1,43 @@
+import { Mutex, MutexInterface, withTimeout } from 'async-mutex';
+
+import { getOptions } from './optionsUtils';
+import { OptionCodename, OptionValues } from './optionsPrototype';
+
+export default class OptionsProvider {
+ private optionValues: OptionValues;
+ private isStale = true;
+ private mutex: MutexInterface = withTimeout(new Mutex(), 60 * 1000);
+
+ constructor() {
+ // If the extension settings change, set the current cached value as stale.
+ // We could try only doing this only when we're sure it has changed, but
+ // there are many factors (if the user has changed it manually, if a kill
+ // switch was activated, etc.) so we'll do it every time.
+ chrome.storage.onChanged.addListener((_, areaName) => {
+ if (areaName !== 'sync') return;
+ console.debug('[optionsWatcher] Marking options as stale.');
+ this.isStale = true;
+ });
+ }
+
+ // Returns a promise resolving to the value of option |option|.
+ getOption<O extends OptionCodename>(option: O): Promise<OptionValues[O]> {
+ // When the cached value is marked as stale, it might be possible that there
+ // is a flood of calls to isEnabled(), which in turn causes a flood of calls
+ // to getOptions() because it takes some time for it to be marked as not
+ // stale. Thus, hiding the logic behind a mutex fixes this.
+ return this.mutex.runExclusive(async () => {
+ if (!this.isStale) return Promise.resolve(this.optionValues[option]);
+
+ this.optionValues = await getOptions();
+ this.isStale = false;
+ return this.optionValues[option];
+ });
+ }
+
+ // Returns a promise resolving to whether the |feature| is enabled.
+ async isEnabled(option: OptionCodename) {
+ const value = await this.getOption(option);
+ return value === true;
+ }
+}
diff --git a/src/common/architecture/dependenciesProvider/DependenciesProvider.ts b/src/common/architecture/dependenciesProvider/DependenciesProvider.ts
index b6af2a1..105e6ac 100644
--- a/src/common/architecture/dependenciesProvider/DependenciesProvider.ts
+++ b/src/common/architecture/dependenciesProvider/DependenciesProvider.ts
@@ -1,11 +1,14 @@
import ExtraInfo from '../../../features/extraInfo/core';
import AutoRefresh from '../../../features/autoRefresh/core/autoRefresh';
+import OptionsProvider from '../../OptionsProvider';
export const AutoRefreshDependency = 'autoRefresh';
export const ExtraInfoDependency = 'extraInfo';
+export const OptionsProviderDependency = 'optionsProvider';
export const DependenciesToClass = {
[AutoRefreshDependency]: AutoRefresh,
[ExtraInfoDependency]: ExtraInfo,
+ [OptionsProviderDependency]: OptionsProvider,
};
interface OurWindow extends Window {
diff --git a/src/common/partialOptionsWatcher.js b/src/common/partialOptionsWatcher.js
index 3c6cec2..261a6d4 100644
--- a/src/common/partialOptionsWatcher.js
+++ b/src/common/partialOptionsWatcher.js
@@ -2,6 +2,9 @@
import {getOptions} from './optionsUtils.js';
+/**
+ * @deprecated Use {@link OptionsProvider} instead.
+ */
export default class PartialOptionsWatcher {
constructor(options) {
this.watchedOptions = options;