diff options
Diffstat (limited to 'toolkit/components/extensions/child/ext-storage.js')
| -rw-r--r-- | toolkit/components/extensions/child/ext-storage.js | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/toolkit/components/extensions/child/ext-storage.js b/toolkit/components/extensions/child/ext-storage.js new file mode 100644 index 0000000000..e754305ee4 --- /dev/null +++ b/toolkit/components/extensions/child/ext-storage.js @@ -0,0 +1,353 @@ +/* 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/. */ + +"use strict"; + +ChromeUtils.defineModuleGetter( + this, + "ExtensionStorage", + "resource://gre/modules/ExtensionStorage.jsm" +); +ChromeUtils.defineModuleGetter( + this, + "ExtensionStorageIDB", + "resource://gre/modules/ExtensionStorageIDB.jsm" +); +ChromeUtils.defineModuleGetter( + this, + "ExtensionTelemetry", + "resource://gre/modules/ExtensionTelemetry.jsm" +); + +// Wrap a storage operation in a TelemetryStopWatch. +async function measureOp(telemetryMetric, extension, fn) { + const stopwatchKey = {}; + telemetryMetric.stopwatchStart(extension, stopwatchKey); + try { + let result = await fn(); + telemetryMetric.stopwatchFinish(extension, stopwatchKey); + return result; + } catch (err) { + telemetryMetric.stopwatchCancel(extension, stopwatchKey); + throw err; + } +} + +this.storage = class extends ExtensionAPI { + getLocalFileBackend(context, { deserialize, serialize }) { + return { + get(keys) { + return measureOp( + ExtensionTelemetry.storageLocalGetJSON, + context.extension, + () => { + return context.childManager + .callParentAsyncFunction("storage.local.JSONFileBackend.get", [ + serialize(keys), + ]) + .then(deserialize); + } + ); + }, + set(items) { + return measureOp( + ExtensionTelemetry.storageLocalSetJSON, + context.extension, + () => { + return context.childManager.callParentAsyncFunction( + "storage.local.JSONFileBackend.set", + [serialize(items)] + ); + } + ); + }, + remove(keys) { + return context.childManager.callParentAsyncFunction( + "storage.local.JSONFileBackend.remove", + [serialize(keys)] + ); + }, + clear() { + return context.childManager.callParentAsyncFunction( + "storage.local.JSONFileBackend.clear", + [] + ); + }, + }; + } + + getLocalIDBBackend(context, { fireOnChanged, serialize, storagePrincipal }) { + let dbPromise; + async function getDB() { + if (dbPromise) { + return dbPromise; + } + + const persisted = context.extension.hasPermission("unlimitedStorage"); + dbPromise = ExtensionStorageIDB.open(storagePrincipal, persisted).catch( + err => { + // Reset the cached promise if it has been rejected, so that the next + // API call is going to retry to open the DB. + dbPromise = null; + throw err; + } + ); + + return dbPromise; + } + + return { + get(keys) { + return measureOp( + ExtensionTelemetry.storageLocalGetIDB, + context.extension, + async () => { + const db = await getDB(); + return db.get(keys); + } + ); + }, + set(items) { + return measureOp( + ExtensionTelemetry.storageLocalSetIDB, + context.extension, + async () => { + const db = await getDB(); + const changes = await db.set(items, { + serialize: ExtensionStorage.serialize, + }); + + if (changes) { + fireOnChanged(changes); + } + } + ); + }, + async remove(keys) { + const db = await getDB(); + const changes = await db.remove(keys); + + if (changes) { + fireOnChanged(changes); + } + }, + async clear() { + const db = await getDB(); + const changes = await db.clear(context.extension); + + if (changes) { + fireOnChanged(changes); + } + }, + }; + } + + getAPI(context) { + const { extension } = context; + const serialize = ExtensionStorage.serializeForContext.bind(null, context); + const deserialize = ExtensionStorage.deserializeForContext.bind( + null, + context + ); + + // onChangedName is "storage.onChanged", "storage.sync.onChanged", etc. + function makeOnChangedEventTarget(onChangedName) { + return new EventManager({ + context, + name: onChangedName, + register: fire => { + let onChanged = (data, area) => { + let changes = new context.cloneScope.Object(); + for (let [key, value] of Object.entries(data)) { + changes[key] = deserialize(value); + } + if (area) { + // storage.onChanged includes the area. + fire.raw(changes, area); + } else { + // StorageArea.onChanged doesn't include the area. + fire.raw(changes); + } + }; + + let parent = context.childManager.getParentEvent(onChangedName); + parent.addListener(onChanged); + return () => { + parent.removeListener(onChanged); + }; + }, + }).api(); + } + + function sanitize(items) { + // The schema validator already takes care of arrays (which are only allowed + // to contain strings). Strings and null are safe values. + if (typeof items != "object" || items === null || Array.isArray(items)) { + return items; + } + // If we got here, then `items` is an object generated by `ObjectType`'s + // `normalize` method from Schemas.jsm. The object returned by `normalize` + // lives in this compartment, while the values live in compartment of + // `context.contentWindow`. The `sanitize` method runs with the principal + // of `context`, so we cannot just use `ExtensionStorage.sanitize` because + // it is not allowed to access properties of `items`. + // So we enumerate all properties and sanitize each value individually. + let sanitized = {}; + for (let [key, value] of Object.entries(items)) { + sanitized[key] = ExtensionStorage.sanitize(value, context); + } + return sanitized; + } + + function fireOnChanged(changes) { + // This call is used (by the storage.local API methods for the IndexedDB backend) to fire a storage.onChanged event, + // it uses the underlying message manager since the child context (or its ProxyContentParent counterpart + // running in the main process) may be gone by the time we call this, and so we can't use the childManager + // abstractions (e.g. callParentAsyncFunction or callParentFunctionNoReturn). + Services.cpmm.sendAsyncMessage( + `Extension:StorageLocalOnChanged:${extension.uuid}`, + changes + ); + } + + // If the selected backend for the extension is not known yet, we have to lazily detect it + // by asking to the main process (as soon as the storage.local API has been accessed for + // the first time). + const getStorageLocalBackend = async () => { + const { + backendEnabled, + storagePrincipal, + } = await ExtensionStorageIDB.selectBackend(context); + + if (!backendEnabled) { + return this.getLocalFileBackend(context, { deserialize, serialize }); + } + + return this.getLocalIDBBackend(context, { + storagePrincipal, + fireOnChanged, + serialize, + }); + }; + + // Synchronously select the backend if it is already known. + let selectedBackend; + + const useStorageIDBBackend = extension.getSharedData("storageIDBBackend"); + if (useStorageIDBBackend === false) { + selectedBackend = this.getLocalFileBackend(context, { + deserialize, + serialize, + }); + } else if (useStorageIDBBackend === true) { + selectedBackend = this.getLocalIDBBackend(context, { + storagePrincipal: extension.getSharedData("storageIDBPrincipal"), + fireOnChanged, + serialize, + }); + } + + let promiseStorageLocalBackend; + + // Generate the backend-agnostic local API wrapped methods. + const local = { + onChanged: makeOnChangedEventTarget("storage.local.onChanged"), + }; + for (let method of ["get", "set", "remove", "clear"]) { + local[method] = async function(...args) { + try { + // Discover the selected backend if it is not known yet. + if (!selectedBackend) { + if (!promiseStorageLocalBackend) { + promiseStorageLocalBackend = getStorageLocalBackend().catch( + err => { + // Clear the cached promise if it has been rejected. + promiseStorageLocalBackend = null; + throw err; + } + ); + } + + // If the storage.local method is not 'get' (which doesn't change any of the stored data), + // fall back to call the method in the parent process, so that it can be completed even + // if this context has been destroyed in the meantime. + if (method !== "get") { + // Let the outer try to catch rejections returned by the backend methods. + try { + const result = await context.childManager.callParentAsyncFunction( + "storage.local.callMethodInParentProcess", + [method, args] + ); + return result; + } catch (err) { + // Just return the rejection as is, the error has been normalized in the + // parent process by callMethodInParentProcess and the original error + // logged in the browser console. + return Promise.reject(err); + } + } + + // Get the selected backend and cache it for the next API calls from this context. + selectedBackend = await promiseStorageLocalBackend; + } + + // Let the outer try to catch rejections returned by the backend methods. + const result = await selectedBackend[method](...args); + return result; + } catch (err) { + throw ExtensionStorageIDB.normalizeStorageError({ + error: err, + extensionId: extension.id, + storageMethod: method, + }); + } + }; + } + + return { + storage: { + local, + + sync: { + get(keys) { + keys = sanitize(keys); + return context.childManager.callParentAsyncFunction( + "storage.sync.get", + [keys] + ); + }, + set(items) { + items = sanitize(items); + return context.childManager.callParentAsyncFunction( + "storage.sync.set", + [items] + ); + }, + onChanged: makeOnChangedEventTarget("storage.sync.onChanged"), + }, + + managed: { + get(keys) { + return context.childManager + .callParentAsyncFunction("storage.managed.get", [serialize(keys)]) + .then(deserialize); + }, + set(items) { + return Promise.reject({ message: "storage.managed is read-only" }); + }, + remove(keys) { + return Promise.reject({ message: "storage.managed is read-only" }); + }, + clear() { + return Promise.reject({ message: "storage.managed is read-only" }); + }, + + onChanged: makeOnChangedEventTarget("storage.managed.onChanged"), + }, + + onChanged: makeOnChangedEventTarget("storage.onChanged"), + }, + }; + } +}; |