PS-1133 Feature/mv3 browser observable memory caching (#3245)

* Create sessions sync structure

* Add observing to session-syncer

* Do not run syncer logic in decorator tests

* Extract test constants

* Change Observables to BehaviorSubject

* Move sendMessage to static method in BrowserApi

* Implement session sync

* only watch in manifest v3

* Use session sync on folder service

* Add array observable sync

* Bypass cache on update from message

* Create feature and dev flags for browser

* Protect development-only methods with decorator

* Improve todo comments for long-term residency

* Use class properties in init

* Do not reuse mocks

* Use json (de)serialization patterns

* Fix failing session storage in dev environment

* Split up complex EncString constructor

* Default false for decrypted session storage

* Try removing hydrate EncString method

* PR review

* PR test review

.eslintignore

@@ -8,6 +8,7 @@
 **/jest.config.js
 **/gulpfile.js
 
+apps/browser/config/config.js
 apps/browser/src/content/autofill.js
 apps/browser/src/scripts/duo.js
 
@@ -18,3 +19,5 @@ apps/web/config.js
 apps/web/scripts/*.js
 apps/web/src/theme.js
 apps/web/tailwind.config.js
+
+apps/cli/config/config.js

apps/browser/config/base.json

@@ -0,0 +1,4 @@
+{
+  "dev_flags": {},
+  "flags": {}
+}

apps/browser/config/config.js

@@ -0,0 +1,30 @@
+function load(envName) {
+  return {
+    ...loadConfig(envName),
+    ...loadConfig("local"),
+  };
+}
+
+function log(configObj) {
+  const repeatNum = 50;
+  console.log(`${"=".repeat(repeatNum)}\nenvConfig`);
+  console.log(JSON.stringify(configObj, null, 2));
+  console.log(`${"=".repeat(repeatNum)}`);
+}
+
+function loadConfig(configName) {
+  try {
+    return require(`./${configName}.json`);
+  } catch (e) {
+    if (e instanceof Error && e.code === "MODULE_NOT_FOUND") {
+      return {};
+    } else {
+      throw e;
+    }
+  }
+}
+
+module.exports = {
+  load,
+  log,
+};

apps/browser/config/development.json

@@ -0,0 +1,6 @@
+{
+  "devFlags": {
+    "storeSessionDecrypted": false
+  },
+  "flags": {}
+}

apps/browser/config/production.json

@@ -0,0 +1,3 @@
+{
+  "flags": {}
+}

apps/browser/src/background/main.background.ts

@@ -54,7 +54,6 @@ import { EventService } from "@bitwarden/common/services/event.service";
 import { ExportService } from "@bitwarden/common/services/export.service";
 import { FileUploadService } from "@bitwarden/common/services/fileUpload.service";
 import { FolderApiService } from "@bitwarden/common/services/folder/folder-api.service";
-import { FolderService } from "@bitwarden/common/services/folder/folder.service";
 import { KeyConnectorService } from "@bitwarden/common/services/keyConnector.service";
 import { MemoryStorageService } from "@bitwarden/common/services/memoryStorage.service";
 import { NotificationsService } from "@bitwarden/common/services/notifications.service";
@@ -90,6 +89,7 @@ import BrowserLocalStorageService from "../services/browserLocalStorage.service"
 import BrowserMessagingService from "../services/browserMessaging.service";
 import BrowserMessagingPrivateModeBackgroundService from "../services/browserMessagingPrivateModeBackground.service";
 import BrowserPlatformUtilsService from "../services/browserPlatformUtils.service";
+import { FolderService } from "../services/folders/folder.service";
 import I18nService from "../services/i18n.service";
 import { KeyGenerationService } from "../services/keyGeneration.service";
 import { LocalBackedSessionStorageService } from "../services/localBackedSessionStorage.service";

apps/browser/src/browser/browserApi.ts

@@ -115,6 +115,11 @@ export class BrowserApi {
     );
   }
 
+  static sendMessage(subscriber: string, arg: any = {}) {
+    const message = Object.assign({}, { command: subscriber }, arg);
+    return chrome.runtime.sendMessage(message);
+  }
+
   static async closeLoginTab() {
     const tabs = await BrowserApi.tabsQuery({
       active: true,

apps/browser/src/decorators/dev-flag.decorator.spec.ts

@@ -0,0 +1,35 @@
+import { devFlagEnabled } from "../flags";
+
+import { devFlag } from "./dev-flag.decorator";
+
+let devFlagEnabledMock: jest.Mock;
+jest.mock("../flags", () => ({
+  ...jest.requireActual("../flags"),
+  devFlagEnabled: jest.fn(),
+}));
+
+class TestClass {
+  @devFlag("storeSessionDecrypted") test() {
+    return "test";
+  }
+}
+
+describe("devFlag decorator", () => {
+  beforeEach(() => {
+    devFlagEnabledMock = devFlagEnabled as jest.Mock;
+  });
+
+  it("should throw an error if the dev flag is disabled", () => {
+    devFlagEnabledMock.mockReturnValue(false);
+    expect(() => {
+      new TestClass().test();
+    }).toThrowError("This method should not be called, it is protected by a disabled dev flag.");
+  });
+
+  it("should not throw an error if the dev flag is enabled", () => {
+    devFlagEnabledMock.mockReturnValue(true);
+    expect(() => {
+      new TestClass().test();
+    }).not.toThrowError();
+  });
+});

apps/browser/src/decorators/dev-flag.decorator.ts

@@ -0,0 +1,15 @@
+import { devFlagEnabled, DevFlagName } from "../flags";
+
+export function devFlag(flag: DevFlagName) {
+  return function (target: any, propertyKey: string, descriptor: PropertyDescriptor) {
+    const originalMethod = descriptor.value;
+    descriptor.value = function (...args: any[]) {
+      if (!devFlagEnabled(flag)) {
+        throw new Error(
+          `This method should not be called, it is protected by a disabled dev flag.`
+        );
+      }
+      return originalMethod.apply(this, args);
+    };
+  };
+}

apps/browser/src/decorators/session-sync-observable/browser-session.decorator.spec.ts

@@ -0,0 +1,64 @@
+import { BehaviorSubject } from "rxjs";
+
+import { StateService } from "../../services/state.service";
+
+import { browserSession } from "./browser-session.decorator";
+import { SessionStorable } from "./session-storable";
+import { sessionSync } from "./session-sync.decorator";
+
+// browserSession initializes SessionSyncers for each sessionSync decorated property
+// We don't want to test SessionSyncers, so we'll mock them
+jest.mock("./session-syncer");
+
+describe("browserSession decorator", () => {
+  it("should throw if StateService is not a constructor argument", () => {
+    @browserSession
+    class TestClass {}
+    expect(() => {
+      new TestClass();
+    }).toThrowError(
+      "Cannot decorate TestClass with browserSession, Browser's StateService must be injected"
+    );
+  });
+
+  it("should create if StateService is a constructor argument", () => {
+    const stateService = Object.create(StateService.prototype, {});
+
+    @browserSession
+    class TestClass {
+      constructor(private stateService: StateService) {}
+    }
+
+    expect(new TestClass(stateService)).toBeDefined();
+  });
+
+  describe("interaction with @sessionSync decorator", () => {
+    let stateService: StateService;
+
+    @browserSession
+    class TestClass {
+      @sessionSync({ initializer: (s: string) => s })
+      behaviorSubject = new BehaviorSubject("");
+
+      constructor(private stateService: StateService) {}
+
+      fromJSON(json: any) {
+        this.behaviorSubject.next(json);
+      }
+    }
+
+    beforeEach(() => {
+      stateService = Object.create(StateService.prototype, {}) as StateService;
+    });
+
+    it("should create a session syncer", () => {
+      const testClass = new TestClass(stateService) as any as SessionStorable;
+      expect(testClass.__sessionSyncers.length).toEqual(1);
+    });
+
+    it("should initialize the session syncer", () => {
+      const testClass = new TestClass(stateService) as any as SessionStorable;
+      expect(testClass.__sessionSyncers[0].init).toHaveBeenCalled();
+    });
+  });
+});

apps/browser/src/decorators/session-sync-observable/browser-session.decorator.ts

@@ -0,0 +1,47 @@
+import { Constructor } from "type-fest";
+
+import { StateService } from "../../services/state.service";
+
+import { SessionStorable } from "./session-storable";
+import { SessionSyncer } from "./session-syncer";
+import { SyncedItemMetadata } from "./sync-item-metadata";
+
+/**
+ * Mark the class as syncing state across the browser session. This decorator finds rxjs BehaviorSubject properties
+ * marked with @sessionSync and syncs these values across the browser session.
+ *
+ * @param constructor
+ * @returns A new constructor that extends the original one to add session syncing.
+ */
+export function browserSession<TCtor extends Constructor<any>>(constructor: TCtor) {
+  return class extends constructor implements SessionStorable {
+    __syncedItemMetadata: SyncedItemMetadata[];
+    __sessionSyncers: SessionSyncer[];
+
+    constructor(...args: any[]) {
+      super(...args);
+
+      // Require state service to be injected
+      const stateService = args.find((arg) => arg instanceof StateService);
+      if (!stateService) {
+        throw new Error(
+          `Cannot decorate ${constructor.name} with browserSession, Browser's StateService must be injected`
+        );
+      }
+
+      if (this.__syncedItemMetadata == null || !(this.__syncedItemMetadata instanceof Array)) {
+        return;
+      }
+
+      this.__sessionSyncers = this.__syncedItemMetadata.map((metadata) =>
+        this.buildSyncer(metadata, stateService)
+      );
+    }
+
+    buildSyncer(metadata: SyncedItemMetadata, stateService: StateService) {
+      const syncer = new SessionSyncer((this as any)[metadata.key], stateService, metadata);
+      syncer.init();
+      return syncer;
+    }
+  };
+}

apps/browser/src/decorators/session-sync-observable/index.ts

@@ -0,0 +1,2 @@
+export { browserSession } from "./browser-session.decorator";
+export { sessionSync } from "./session-sync.decorator";

apps/browser/src/decorators/session-sync-observable/session-storable.ts

@@ -0,0 +1,7 @@
+import { SessionSyncer } from "./session-syncer";
+import { SyncedItemMetadata } from "./sync-item-metadata";
+
+export interface SessionStorable {
+  __syncedItemMetadata: SyncedItemMetadata[];
+  __sessionSyncers: SessionSyncer[];
+}

apps/browser/src/decorators/session-sync-observable/session-sync.decorator.spec.ts

@@ -0,0 +1,23 @@
+import { BehaviorSubject } from "rxjs";
+
+import { sessionSync } from "./session-sync.decorator";
+
+describe("sessionSync decorator", () => {
+  const initializer = (s: string) => "test";
+  const ctor = String;
+  class TestClass {
+    @sessionSync({ ctor: ctor, initializer: initializer })
+    testProperty = new BehaviorSubject("");
+  }
+
+  it("should add __syncedItemKeys to prototype", () => {
+    const testClass = new TestClass();
+    expect((testClass as any).__syncedItemMetadata).toEqual([
+      expect.objectContaining({
+        key: "TestClass_testProperty",
+        ctor: ctor,
+        initializer: initializer,
+      }),
+    ]);
+  });
+});

apps/browser/src/decorators/session-sync-observable/session-sync.decorator.ts

@@ -0,0 +1,51 @@
+import { Jsonify } from "type-fest";
+
+import { SessionStorable } from "./session-storable";
+
+class BuildOptions<T> {
+  ctor?: new () => T;
+  initializer?: (keyValuePair: Jsonify<T>) => T;
+  initializeAsArray? = false;
+}
+
+/**
+ * A decorator used to indicate the BehaviorSubject should be synced for this browser session across all contexts.
+ *
+ * >**Note** This decorator does nothing if the enclosing class is not decorated with @browserSession.
+ *
+ * >**Note** The Behavior subject must be initialized with a default or in the constructor of the class. If it is not, an error will be thrown.
+ *
+ * >**!!Warning!!** If the property is overwritten at any time, the new value will not be synced across the browser session.
+ *
+ * @param buildOptions
+ * Builders for the value, requires either a constructor (ctor) for your BehaviorSubject type or an
+ * initializer function that takes a key value pair representation of the BehaviorSubject data
+ * and returns your instantiated BehaviorSubject value. `initializeAsArray can optionally be used to indicate
+ * the provided initializer function should be used to build an array of values. For example,
+ * ```ts
+ * \@sessionSync({ initializer: Foo.fromJSON, initializeAsArray: true })
+ * ```
+ * is equivalent to
+ * ```
+ * \@sessionSync({ initializer: (obj: any[]) => obj.map((f) => Foo.fromJSON })
+ * ```
+ *
+ * @returns decorator function
+ */
+export function sessionSync<T>(buildOptions: BuildOptions<T>) {
+  return (prototype: unknown, propertyKey: string) => {
+    // Force prototype into SessionStorable and implement it.
+    const p = prototype as SessionStorable;
+
+    if (p.__syncedItemMetadata == null) {
+      p.__syncedItemMetadata = [];
+    }
+
+    p.__syncedItemMetadata.push({
+      key: `${prototype.constructor.name}_${propertyKey}`,
+      ctor: buildOptions.ctor,
+      initializer: buildOptions.initializer,
+      initializeAsArray: buildOptions.initializeAsArray,
+    });
+  };
+}

apps/browser/src/decorators/session-sync-observable/session-syncer.spec.ts

@@ -0,0 +1,156 @@
+import { mock, MockProxy } from "jest-mock-extended";
+import { BehaviorSubject } from "rxjs";
+
+import { BrowserApi } from "../../browser/browserApi";
+import { StateService } from "../../services/abstractions/state.service";
+
+import { SessionSyncer } from "./session-syncer";
+
+describe("session syncer", () => {
+  const key = "Test__behaviorSubject";
+  const metaData = { key, initializer: (s: string) => s };
+  let stateService: MockProxy<StateService>;
+  let sut: SessionSyncer;
+  let behaviorSubject: BehaviorSubject<string>;
+
+  beforeEach(() => {
+    behaviorSubject = new BehaviorSubject<string>("");
+    jest.spyOn(chrome.runtime, "getManifest").mockReturnValue({
+      name: "bitwarden-test",
+      version: "0.0.0",
+      manifest_version: 3,
+    });
+
+    stateService = mock<StateService>();
+    sut = new SessionSyncer(behaviorSubject, stateService, metaData);
+  });
+
+  afterEach(() => {
+    jest.resetAllMocks();
+
+    behaviorSubject.unsubscribe();
+  });
+
+  describe("constructor", () => {
+    it("should throw if behaviorSubject is not an instance of BehaviorSubject", () => {
+      expect(() => {
+        new SessionSyncer({} as any, stateService, null);
+      }).toThrowError("behaviorSubject must be an instance of BehaviorSubject");
+    });
+
+    it("should create if either ctor or initializer is provided", () => {
+      expect(
+        new SessionSyncer(behaviorSubject, stateService, { key: key, ctor: String })
+      ).toBeDefined();
+      expect(
+        new SessionSyncer(behaviorSubject, stateService, {
+          key: key,
+          initializer: (s: any) => s,
+        })
+      ).toBeDefined();
+    });
+    it("should throw if neither ctor or initializer is provided", () => {
+      expect(() => {
+        new SessionSyncer(behaviorSubject, stateService, { key: key });
+      }).toThrowError("ctor or initializer must be provided");
+    });
+  });
+
+  describe("manifest v2 init", () => {
+    let observeSpy: jest.SpyInstance;
+    let listenForUpdatesSpy: jest.SpyInstance;
+
+    beforeEach(() => {
+      observeSpy = jest.spyOn(behaviorSubject, "subscribe").mockReturnThis();
+      listenForUpdatesSpy = jest.spyOn(BrowserApi, "messageListener").mockReturnValue();
+      jest.spyOn(chrome.runtime, "getManifest").mockReturnValue({
+        name: "bitwarden-test",
+        version: "0.0.0",
+        manifest_version: 2,
+      });
+
+      sut.init();
+    });
+
+    it("should not start observing", () => {
+      expect(observeSpy).not.toHaveBeenCalled();
+    });
+
+    it("should not start listening", () => {
+      expect(listenForUpdatesSpy).not.toHaveBeenCalled();
+    });
+  });
+
+  describe("a value is emitted on the observable", () => {
+    let sendMessageSpy: jest.SpyInstance;
+
+    beforeEach(() => {
+      sendMessageSpy = jest.spyOn(BrowserApi, "sendMessage");
+
+      sut.init();
+
+      behaviorSubject.next("test");
+    });
+
+    it("should update the session memory", async () => {
+      // await finishing of fire-and-forget operation
+      await new Promise((resolve) => setTimeout(resolve, 100));
+      expect(stateService.setInSessionMemory).toHaveBeenCalledTimes(1);
+      expect(stateService.setInSessionMemory).toHaveBeenCalledWith(key, "test");
+    });
+
+    it("should update sessionSyncers in other contexts", async () => {
+      // await finishing of fire-and-forget operation
+      await new Promise((resolve) => setTimeout(resolve, 100));
+
+      expect(sendMessageSpy).toHaveBeenCalledTimes(1);
+      expect(sendMessageSpy).toHaveBeenCalledWith(`${key}_update`, { id: sut.id });
+    });
+  });
+
+  describe("A message is received", () => {
+    let nextSpy: jest.SpyInstance;
+    let sendMessageSpy: jest.SpyInstance;
+
+    beforeEach(() => {
+      nextSpy = jest.spyOn(behaviorSubject, "next");
+      sendMessageSpy = jest.spyOn(BrowserApi, "sendMessage");
+
+      sut.init();
+    });
+
+    afterEach(() => {
+      jest.resetAllMocks();
+    });
+
+    it("should ignore messages with the wrong command", async () => {
+      await sut.updateFromMessage({ command: "wrong_command", id: sut.id });
+
+      expect(stateService.getFromSessionMemory).not.toHaveBeenCalled();
+      expect(nextSpy).not.toHaveBeenCalled();
+    });
+
+    it("should ignore messages from itself", async () => {
+      await sut.updateFromMessage({ command: `${key}_update`, id: sut.id });
+
+      expect(stateService.getFromSessionMemory).not.toHaveBeenCalled();
+      expect(nextSpy).not.toHaveBeenCalled();
+    });
+
+    it("should update from message on emit from another instance", async () => {
+      stateService.getFromSessionMemory.mockResolvedValue("test");
+
+      await sut.updateFromMessage({ command: `${key}_update`, id: "different_id" });
+
+      expect(stateService.getFromSessionMemory).toHaveBeenCalledTimes(1);
+      expect(stateService.getFromSessionMemory).toHaveBeenCalledWith(key);
+
+      expect(nextSpy).toHaveBeenCalledTimes(1);
+      expect(nextSpy).toHaveBeenCalledWith("test");
+      expect(behaviorSubject.value).toBe("test");
+
+      // Expect no circular messaging
+      expect(sendMessageSpy).toHaveBeenCalledTimes(0);
+    });
+  });
+});

apps/browser/src/decorators/session-sync-observable/session-syncer.ts

@@ -0,0 +1,79 @@
+import { BehaviorSubject, Subscription } from "rxjs";
+
+import { Utils } from "@bitwarden/common/misc/utils";
+
+import { BrowserApi } from "../../browser/browserApi";
+import { StateService } from "../../services/abstractions/state.service";
+
+import { SyncedItemMetadata } from "./sync-item-metadata";
+
+export class SessionSyncer {
+  subscription: Subscription;
+  id = Utils.newGuid();
+
+  // everyone gets the same initial values
+  private ignoreNextUpdate = true;
+
+  constructor(
+    private behaviorSubject: BehaviorSubject<any>,
+    private stateService: StateService,
+    private metaData: SyncedItemMetadata
+  ) {
+    if (!(behaviorSubject instanceof BehaviorSubject)) {
+      throw new Error("behaviorSubject must be an instance of BehaviorSubject");
+    }
+
+    if (metaData.ctor == null && metaData.initializer == null) {
+      throw new Error("ctor or initializer must be provided");
+    }
+  }
+
+  init() {
+    if (chrome.runtime.getManifest().manifest_version != 3) {
+      return;
+    }
+
+    this.observe();
+    this.listenForUpdates();
+  }
+
+  private observe() {
+    // This may be a memory leak.
+    // There is no good time to unsubscribe from this observable. Hopefully Manifest V3 clears memory from temporary
+    // contexts. If so, this is handled by destruction of the context.
+    this.subscription = this.behaviorSubject.subscribe(async (next) => {
+      if (this.ignoreNextUpdate) {
+        this.ignoreNextUpdate = false;
+        return;
+      }
+      await this.updateSession(next);
+    });
+  }
+
+  private listenForUpdates() {
+    // This is an unawaited promise, but it will be executed asynchronously in the background.
+    BrowserApi.messageListener(
+      this.updateMessageCommand,
+      async (message) => await this.updateFromMessage(message)
+    );
+  }
+
+  async updateFromMessage(message: any) {
+    if (message.command != this.updateMessageCommand || message.id === this.id) {
+      return;
+    }
+    const keyValuePair = await this.stateService.getFromSessionMemory(this.metaData.key);
+    const value = SyncedItemMetadata.buildFromKeyValuePair(keyValuePair, this.metaData);
+    this.ignoreNextUpdate = true;
+    this.behaviorSubject.next(value);
+  }
+
+  private async updateSession(value: any) {
+    await this.stateService.setInSessionMemory(this.metaData.key, value);
+    await BrowserApi.sendMessage(this.updateMessageCommand, { id: this.id });
+  }
+
+  private get updateMessageCommand() {
+    return `${this.metaData.key}_update`;
+  }
+}

apps/browser/src/decorators/session-sync-observable/sync-item-metadata.ts

@@ -0,0 +1,22 @@
+export class SyncedItemMetadata {
+  key: string;
+  ctor?: new () => any;
+  initializer?: (keyValuePair: any) => any;
+  initializeAsArray?: boolean;
+
+  static buildFromKeyValuePair(keyValuePair: any, metadata: SyncedItemMetadata): any {
+    const builder = SyncedItemMetadata.getBuilder(metadata);
+
+    if (metadata.initializeAsArray) {
+      return keyValuePair.map((o: any) => builder(o));
+    } else {
+      return builder(keyValuePair);
+    }
+  }
+
+  private static getBuilder(metadata: SyncedItemMetadata): (o: any) => any {
+    return metadata.initializer != null
+      ? metadata.initializer
+      : (o: any) => Object.assign(new metadata.ctor(), o);
+  }
+}

apps/browser/src/decorators/session-sync-observable/synced-item-metadata.spec.ts

@@ -0,0 +1,54 @@
+import { SyncedItemMetadata } from "./sync-item-metadata";
+
+describe("build from key value pair", () => {
+  const key = "key";
+  const initializer = (s: any) => "used initializer";
+  class TestClass {}
+  const ctor = TestClass;
+
+  it("should call initializer if provided", () => {
+    const actual = SyncedItemMetadata.buildFromKeyValuePair(
+      {},
+      {
+        key: "key",
+        initializer: initializer,
+      }
+    );
+
+    expect(actual).toEqual("used initializer");
+  });
+
+  it("should call ctor if provided", () => {
+    const expected = { provided: "value" };
+    const actual = SyncedItemMetadata.buildFromKeyValuePair(expected, {
+      key: key,
+      ctor: ctor,
+    });
+
+    expect(actual).toBeInstanceOf(ctor);
+    expect(actual).toEqual(expect.objectContaining(expected));
+  });
+
+  it("should prefer using initializer if both are provided", () => {
+    const actual = SyncedItemMetadata.buildFromKeyValuePair(
+      {},
+      {
+        key: key,
+        initializer: initializer,
+        ctor: ctor,
+      }
+    );
+
+    expect(actual).toEqual("used initializer");
+  });
+
+  it("should honor initialize as array", () => {
+    const actual = SyncedItemMetadata.buildFromKeyValuePair([1, 2], {
+      key: key,
+      initializer: initializer,
+      initializeAsArray: true,
+    });
+
+    expect(actual).toEqual(["used initializer", "used initializer"]);
+  });
+});

apps/browser/src/flags.ts

@@ -0,0 +1,41 @@
+function getFlags<T>(envFlags: string | T): T {
+  if (typeof envFlags === "string") {
+    return JSON.parse(envFlags) as T;
+  } else {
+    return envFlags as T;
+  }
+}
+
+/* Placeholder for when we have a relevant feature flag
+export type Flags = { test?: boolean };
+export type FlagName = keyof Flags;
+export function flagEnabled(flag: FlagName): boolean {
+  const flags = getFlags<Flags>(process.env.FLAGS);
+  return flags[flag] == null || flags[flag];
+}
+*/
+
+/**
+ * These flags are useful for development and testing.
+ * Dev Flags are always OFF in production.
+ */
+export type DevFlags = {
+  storeSessionDecrypted?: boolean;
+};
+
+export type DevFlagName = keyof DevFlags;
+
+/**
+ * Gets the value of a dev flag from environment.
+ * Will always return false unless in development.
+ * @param flag The name of the dev flag to check
+ * @returns The value of the flag
+ */
+export function devFlagEnabled(flag: DevFlagName): boolean {
+  if (process.env.ENV !== "development") {
+    return false;
+  }
+
+  const devFlags = getFlags<DevFlags>(process.env.DEV_FLAGS);
+  return devFlags[flag] == null || devFlags[flag];
+}

apps/browser/src/services/abstractions/state.service.ts

@@ -7,6 +7,8 @@ import { BrowserGroupingsComponentState } from "src/models/browserGroupingsCompo
 import { BrowserSendComponentState } from "src/models/browserSendComponentState";
 
 export abstract class StateService extends BaseStateServiceAbstraction<Account> {
+  abstract getFromSessionMemory<T>(key: string): Promise<T>;
+  abstract setInSessionMemory(key: string, value: any): Promise<void>;
   getBrowserGroupingComponentState: (
     options?: StorageOptions
   ) => Promise<BrowserGroupingsComponentState>;

apps/browser/src/services/browserMessaging.service.ts

@@ -1,8 +1,9 @@
 import { MessagingService } from "@bitwarden/common/abstractions/messaging.service";
 
+import { BrowserApi } from "../browser/browserApi";
+
 export default class BrowserMessagingService implements MessagingService {
   send(subscriber: string, arg: any = {}) {
-    const message = Object.assign({}, { command: subscriber }, arg);
-    chrome.runtime.sendMessage(message);
+    return BrowserApi.sendMessage(subscriber, arg);
   }
 }

apps/browser/src/services/folders/folder.service.ts

@@ -0,0 +1,15 @@
+import { BehaviorSubject } from "rxjs/internal/BehaviorSubject";
+
+import { Folder } from "@bitwarden/common/models/domain/folder";
+import { FolderView } from "@bitwarden/common/models/view/folderView";
+import { FolderService as BaseFolderService } from "@bitwarden/common/services/folder/folder.service";
+
+import { browserSession, sessionSync } from "../../decorators/session-sync-observable";
+
+@browserSession
+export class FolderService extends BaseFolderService {
+  @sessionSync({ initializer: Folder.fromJSON, initializeAsArray: true })
+  protected _folders: BehaviorSubject<Folder[]>;
+  @sessionSync({ initializer: FolderView.fromJSON, initializeAsArray: true })
+  protected _folderViews: BehaviorSubject<FolderView[]>;
+}

apps/browser/src/services/localBackedSessionStorage.service.ts

@@ -1,8 +1,11 @@
 import { AbstractEncryptService } from "@bitwarden/common/abstractions/abstractEncrypt.service";
-import { AbstractStorageService } from "@bitwarden/common/abstractions/storage.service";
+import { AbstractCachedStorageService } from "@bitwarden/common/abstractions/storage.service";
 import { EncString } from "@bitwarden/common/models/domain/encString";
 import { SymmetricCryptoKey } from "@bitwarden/common/models/domain/symmetricCryptoKey";
 
+import { devFlag } from "../decorators/dev-flag.decorator";
+import { devFlagEnabled } from "../flags";
+
 import { AbstractKeyGenerationService } from "./abstractions/abstractKeyGeneration.service";
 import BrowserLocalStorageService from "./browserLocalStorage.service";
 import BrowserMemoryStorageService from "./browserMemoryStorage.service";
@@ -12,8 +15,8 @@ const keys = {
   sessionKey: "session",
 };
 
-export class LocalBackedSessionStorageService extends AbstractStorageService {
-  private cache = new Map<string, any>();
+export class LocalBackedSessionStorageService extends AbstractCachedStorageService {
+  private cache = new Map<string, unknown>();
   private localStorage = new BrowserLocalStorageService();
   private sessionStorage = new BrowserMemoryStorageService();
 
@@ -26,23 +29,27 @@ export class LocalBackedSessionStorageService extends AbstractStorageService {
 
   async get<T>(key: string): Promise<T> {
     if (this.cache.has(key)) {
-      return this.cache.get(key);
+      return this.cache.get(key) as T;
     }
 
+    return await this.getBypassCache(key);
+  }
+
+  async getBypassCache<T>(key: string): Promise<T> {
     const session = await this.getLocalSession(await this.getSessionEncKey());
     if (session == null || !Object.keys(session).includes(key)) {
       return null;
     }
 
     this.cache.set(key, session[key]);
-    return this.cache.get(key);
+    return this.cache.get(key) as T;
   }
 
   async has(key: string): Promise<boolean> {
     return (await this.get(key)) != null;
   }
 
-  async save(key: string, obj: any): Promise<void> {
+  async save<T>(key: string, obj: T): Promise<void> {
     if (obj == null) {
       this.cache.delete(key);
     } else {
@@ -59,13 +66,17 @@ export class LocalBackedSessionStorageService extends AbstractStorageService {
     await this.save(key, null);
   }
 
-  async getLocalSession(encKey: SymmetricCryptoKey): Promise<any> {
+  async getLocalSession(encKey: SymmetricCryptoKey): Promise<Record<string, unknown>> {
     const local = await this.localStorage.get<string>(keys.sessionKey);
 
     if (local == null) {
       return null;
     }
 
+    if (devFlagEnabled("storeSessionDecrypted")) {
+      return local as any as Record<string, unknown>;
+    }
+
     const sessionJson = await this.encryptService.decryptToUtf8(new EncString(local), encKey);
     if (sessionJson == null) {
       // Error with decryption -- session is lost, delete state and key and start over
@@ -76,7 +87,26 @@ export class LocalBackedSessionStorageService extends AbstractStorageService {
     return JSON.parse(sessionJson);
   }
 
-  async setLocalSession(session: any, key: SymmetricCryptoKey) {
+  async setLocalSession(session: Record<string, unknown>, key: SymmetricCryptoKey) {
+    if (devFlagEnabled("storeSessionDecrypted")) {
+      await this.setDecryptedLocalSession(session);
+    } else {
+      await this.setEncryptedLocalSession(session, key);
+    }
+  }
+
+  @devFlag("storeSessionDecrypted")
+  async setDecryptedLocalSession(session: Record<string, unknown>): Promise<void> {
+    // Make sure we're storing the jsonified version of the session
+    const jsonSession = JSON.parse(JSON.stringify(session));
+    if (session == null) {
+      await this.localStorage.remove(keys.sessionKey);
+    } else {
+      await this.localStorage.save(keys.sessionKey, jsonSession);
+    }
+  }
+
+  async setEncryptedLocalSession(session: Record<string, unknown>, key: SymmetricCryptoKey) {
     const jsonSession = JSON.stringify(session);
     const encSession = await this.encryptService.encrypt(jsonSession, key);
 
@@ -87,14 +117,12 @@ export class LocalBackedSessionStorageService extends AbstractStorageService {
   }
 
   async getSessionEncKey(): Promise<SymmetricCryptoKey> {
-    let storedKey = (await this.sessionStorage.get(keys.encKey)) as SymmetricCryptoKey;
+    let storedKey = await this.sessionStorage.get<SymmetricCryptoKey>(keys.encKey);
     if (storedKey == null || Object.keys(storedKey).length == 0) {
       storedKey = await this.keyGenerationService.makeEphemeralKey();
       await this.setSessionEncKey(storedKey);
     }
-    return SymmetricCryptoKey.fromJSON(
-      Object.create(SymmetricCryptoKey.prototype, Object.getOwnPropertyDescriptors(storedKey))
-    );
+    return SymmetricCryptoKey.fromJSON(storedKey);
   }
 
   async setSessionEncKey(input: SymmetricCryptoKey): Promise<void> {

apps/browser/src/services/state.service.spec.ts

@@ -1,7 +1,10 @@
 import { Substitute, SubstituteOf } from "@fluffy-spoon/substitute";
 
 import { LogService } from "@bitwarden/common/abstractions/log.service";
-import { AbstractStorageService } from "@bitwarden/common/abstractions/storage.service";
+import {
+  AbstractCachedStorageService,
+  AbstractStorageService,
+} from "@bitwarden/common/abstractions/storage.service";
 import { SendType } from "@bitwarden/common/enums/sendType";
 import { StateFactory } from "@bitwarden/common/factories/stateFactory";
 import { GlobalState } from "@bitwarden/common/models/domain/globalState";
@@ -14,12 +17,12 @@ import { BrowserComponentState } from "../models/browserComponentState";
 import { BrowserGroupingsComponentState } from "../models/browserGroupingsComponentState";
 import { BrowserSendComponentState } from "../models/browserSendComponentState";
 
+import { LocalBackedSessionStorageService } from "./localBackedSessionStorage.service";
 import { StateService } from "./state.service";
 
 describe("Browser State Service", () => {
   let secureStorageService: SubstituteOf<AbstractStorageService>;
   let diskStorageService: SubstituteOf<AbstractStorageService>;
-  let memoryStorageService: SubstituteOf<AbstractStorageService>;
   let logService: SubstituteOf<LogService>;
   let stateMigrationService: SubstituteOf<StateMigrationService>;
   let stateFactory: SubstituteOf<StateFactory<GlobalState, Account>>;
@@ -33,7 +36,6 @@ describe("Browser State Service", () => {
   beforeEach(() => {
     secureStorageService = Substitute.for();
     diskStorageService = Substitute.for();
-    memoryStorageService = Substitute.for();
     logService = Substitute.for();
     stateMigrationService = Substitute.for();
     stateFactory = Substitute.for();
@@ -44,66 +46,104 @@ describe("Browser State Service", () => {
       profile: { userId: userId },
     });
     state.activeUserId = userId;
-    const stateGetter = (key: string) => Promise.resolve(JSON.parse(JSON.stringify(state)));
-    memoryStorageService.get("state").mimicks(stateGetter);
-
-    sut = new StateService(
-      diskStorageService,
-      secureStorageService,
-      memoryStorageService,
-      logService,
-      stateMigrationService,
-      stateFactory,
-      useAccountCache
-    );
   });
 
-  describe("getBrowserGroupingComponentState", () => {
-    it("should return a BrowserGroupingsComponentState", async () => {
-      state.accounts[userId].groupings = new BrowserGroupingsComponentState();
+  describe("direct memory storage access", () => {
+    let memoryStorageService: AbstractCachedStorageService;
 
-      const actual = await sut.getBrowserGroupingComponentState();
-      expect(actual).toBeInstanceOf(BrowserGroupingsComponentState);
+    beforeEach(() => {
+      // We need `AbstractCachedStorageService` in the prototype chain to correctly test cache bypass.
+      memoryStorageService = Object.create(LocalBackedSessionStorageService.prototype);
+
+      sut = new StateService(
+        diskStorageService,
+        secureStorageService,
+        memoryStorageService,
+        logService,
+        stateMigrationService,
+        stateFactory,
+        useAccountCache
+      );
+    });
+
+    it("should bypass cache if possible", async () => {
+      const spyBypass = jest
+        .spyOn(memoryStorageService, "getBypassCache")
+        .mockResolvedValue("value");
+      const spyGet = jest.spyOn(memoryStorageService, "get");
+      const result = await sut.getFromSessionMemory("key");
+      expect(spyBypass).toHaveBeenCalled();
+      expect(spyGet).not.toHaveBeenCalled();
+      expect(result).toBe("value");
     });
   });
 
-  describe("getBrowserCipherComponentState", () => {
-    it("should return a BrowserComponentState", async () => {
-      const componentState = new BrowserComponentState();
-      componentState.scrollY = 0;
-      componentState.searchText = "test";
-      state.accounts[userId].ciphers = componentState;
+  describe("state methods", () => {
+    let memoryStorageService: SubstituteOf<AbstractStorageService>;
 
-      const actual = await sut.getBrowserCipherComponentState();
-      expect(actual).toStrictEqual(componentState);
+    beforeEach(() => {
+      memoryStorageService = Substitute.for();
+      const stateGetter = (key: string) => Promise.resolve(JSON.parse(JSON.stringify(state)));
+      memoryStorageService.get("state").mimicks(stateGetter);
+
+      sut = new StateService(
+        diskStorageService,
+        secureStorageService,
+        memoryStorageService,
+        logService,
+        stateMigrationService,
+        stateFactory,
+        useAccountCache
+      );
     });
-  });
 
-  describe("getBrowserSendComponentState", () => {
-    it("should return a BrowserSendComponentState", async () => {
-      const sendState = new BrowserSendComponentState();
-      sendState.sends = [new SendView(), new SendView()];
-      sendState.typeCounts = new Map<SendType, number>([
-        [SendType.File, 3],
-        [SendType.Text, 5],
-      ]);
-      state.accounts[userId].send = sendState;
+    describe("getBrowserGroupingComponentState", () => {
+      it("should return a BrowserGroupingsComponentState", async () => {
+        state.accounts[userId].groupings = new BrowserGroupingsComponentState();
 
-      const actual = await sut.getBrowserSendComponentState();
-      expect(actual).toBeInstanceOf(BrowserSendComponentState);
-      expect(actual).toMatchObject(sendState);
+        const actual = await sut.getBrowserGroupingComponentState();
+        expect(actual).toBeInstanceOf(BrowserGroupingsComponentState);
+      });
     });
-  });
 
-  describe("getBrowserSendTypeComponentState", () => {
-    it("should return a BrowserComponentState", async () => {
-      const componentState = new BrowserComponentState();
-      componentState.scrollY = 0;
-      componentState.searchText = "test";
-      state.accounts[userId].sendType = componentState;
+    describe("getBrowserCipherComponentState", () => {
+      it("should return a BrowserComponentState", async () => {
+        const componentState = new BrowserComponentState();
+        componentState.scrollY = 0;
+        componentState.searchText = "test";
+        state.accounts[userId].ciphers = componentState;
 
-      const actual = await sut.getBrowserSendTypeComponentState();
-      expect(actual).toStrictEqual(componentState);
+        const actual = await sut.getBrowserCipherComponentState();
+        expect(actual).toStrictEqual(componentState);
+      });
+    });
+
+    describe("getBrowserSendComponentState", () => {
+      it("should return a BrowserSendComponentState", async () => {
+        const sendState = new BrowserSendComponentState();
+        sendState.sends = [new SendView(), new SendView()];
+        sendState.typeCounts = new Map<SendType, number>([
+          [SendType.File, 3],
+          [SendType.Text, 5],
+        ]);
+        state.accounts[userId].send = sendState;
+
+        const actual = await sut.getBrowserSendComponentState();
+        expect(actual).toBeInstanceOf(BrowserSendComponentState);
+        expect(actual).toMatchObject(sendState);
+      });
+    });
+
+    describe("getBrowserSendTypeComponentState", () => {
+      it("should return a BrowserComponentState", async () => {
+        const componentState = new BrowserComponentState();
+        componentState.scrollY = 0;
+        componentState.searchText = "test";
+        state.accounts[userId].sendType = componentState;
+
+        const actual = await sut.getBrowserSendTypeComponentState();
+        expect(actual).toStrictEqual(componentState);
+      });
     });
   });
 });

apps/browser/src/services/state.service.ts

@@ -1,3 +1,4 @@
+import { AbstractCachedStorageService } from "@bitwarden/common/abstractions/storage.service";
 import { GlobalState } from "@bitwarden/common/models/domain/globalState";
 import { StorageOptions } from "@bitwarden/common/models/domain/storageOptions";
 import {
@@ -16,6 +17,16 @@ export class StateService
   extends BaseStateService<GlobalState, Account>
   implements StateServiceAbstraction
 {
+  async getFromSessionMemory<T>(key: string): Promise<T> {
+    return this.memoryStorageService instanceof AbstractCachedStorageService
+      ? await this.memoryStorageService.getBypassCache<T>(key)
+      : await this.memoryStorageService.get<T>(key);
+  }
+
+  async setInSessionMemory(key: string, value: any): Promise<void> {
+    await this.memoryStorageService.save(key, value);
+  }
+
   async addAccount(account: Account) {
     // Apply browser overrides to default account values
     account = new Account(account);

apps/browser/test.setup.ts

@@ -1,26 +1,32 @@
 // Add chrome storage api
-const get = jest.fn();
-const set = jest.fn();
-const has = jest.fn();
-const remove = jest.fn();
 const QUOTA_BYTES = 10;
-const getBytesInUse = jest.fn();
-const clear = jest.fn();
-global.chrome = {
-  storage: {
-    local: {
-      set,
-      get,
-      remove,
-      QUOTA_BYTES,
-      getBytesInUse,
-      clear,
-    },
-    session: {
-      set,
-      get,
-      has,
-      remove,
-    },
+const storage = {
+  local: {
+    set: jest.fn(),
+    get: jest.fn(),
+    remove: jest.fn(),
+    QUOTA_BYTES,
+    getBytesInUse: jest.fn(),
+    clear: jest.fn(),
   },
+  session: {
+    set: jest.fn(),
+    get: jest.fn(),
+    has: jest.fn(),
+    remove: jest.fn(),
+  },
+};
+
+const runtime = {
+  onMessage: {
+    addListener: jest.fn(),
+  },
+  sendMessage: jest.fn(),
+  getManifest: jest.fn(),
+};
+
+// set chrome
+global.chrome = {
+  storage,
+  runtime,
 } as any;

apps/browser/webpack.config.js

@@ -6,6 +6,7 @@ const CopyWebpackPlugin = require("copy-webpack-plugin");
 const MiniCssExtractPlugin = require("mini-css-extract-plugin");
 const { AngularWebpackPlugin } = require("@ngtools/webpack");
 const TerserPlugin = require("terser-webpack-plugin");
+const configurator = require("./config/config");
 
 if (process.env.NODE_ENV == null) {
   process.env.NODE_ENV = "development";
@@ -14,6 +15,8 @@ const ENV = (process.env.ENV = process.env.NODE_ENV);
 const manifestVersion = process.env.MANIFEST_VERSION == 3 ? 3 : 2;
 
 console.log(`Building Manifest Version ${manifestVersion} app`);
+const envConfig = configurator.load(ENV);
+configurator.log(envConfig);
 
 const moduleRules = [
   {
@@ -116,6 +119,10 @@ const plugins = [
     exclude: [/content\/.*/, /notification\/.*/],
     filename: "[file].map",
   }),
+  new webpack.EnvironmentPlugin({
+    FLAGS: envConfig.flags,
+    DEV_FLAGS: ENV === "development" ? envConfig.devFlags : {},
+  }),
 ];
 
 const config = {

apps/cli/config/config.js

@@ -1,4 +1,3 @@
-/* eslint-disable no-console */
 function load(envName) {
   return {
     ...loadConfig(envName),

libs/common/spec/models/domain/encString.spec.ts

@@ -192,4 +192,12 @@ describe("EncString", () => {
       cryptoService.received().decryptToUtf8(encString, key);
     });
   });
+
+  describe("toJSON", () => {
+    it("Should be represented by the encrypted string", () => {
+      const encString = new EncString(EncryptionType.AesCbc256_B64, "data", "iv");
+
+      expect(encString.toJSON()).toBe(encString.encryptedString);
+    });
+  });
 });

libs/common/spec/models/domain/folder.spec.ts

@@ -1,4 +1,5 @@
 import { FolderData } from "@bitwarden/common/models/data/folderData";
+import { EncString } from "@bitwarden/common/models/domain/encString";
 import { Folder } from "@bitwarden/common/models/domain/folder";
 
 import { mockEnc } from "../../utils";
@@ -38,4 +39,27 @@ describe("Folder", () => {
       revisionDate: new Date("2022-01-31T12:00:00.000Z"),
     });
   });
+
+  describe("fromJSON", () => {
+    jest.mock("@bitwarden/common/models/domain/encString");
+    const mockFromJson = (stub: any) => (stub + "_fromJSON") as any;
+    jest.spyOn(EncString, "fromJSON").mockImplementation(mockFromJson);
+
+    it("initializes nested objects", () => {
+      const revisionDate = new Date("2022-08-04T01:06:40.441Z");
+      const actual = Folder.fromJSON({
+        revisionDate: revisionDate.toISOString(),
+        name: "name",
+        id: "id",
+      });
+
+      const expected = {
+        revisionDate: revisionDate,
+        name: "name_fromJSON",
+        id: "id",
+      };
+
+      expect(actual).toMatchObject(expected);
+    });
+  });
 });

libs/common/spec/models/view/folderView.spec.ts

@@ -0,0 +1,22 @@
+import { FolderView } from "@bitwarden/common/models/view/folderView";
+
+describe("FolderView", () => {
+  describe("fromJSON", () => {
+    it("initializes nested objects", () => {
+      const revisionDate = new Date("2022-08-04T01:06:40.441Z");
+      const actual = FolderView.fromJSON({
+        revisionDate: revisionDate.toISOString(),
+        name: "name",
+        id: "id",
+      });
+
+      const expected = {
+        revisionDate: revisionDate,
+        name: "name",
+        id: "id",
+      };
+
+      expect(actual).toMatchObject(expected);
+    });
+  });
+});

libs/common/src/abstractions/storage.service.ts

@@ -6,3 +6,7 @@ export abstract class AbstractStorageService {
   abstract save<T>(key: string, obj: T, options?: StorageOptions): Promise<void>;
   abstract remove(key: string, options?: StorageOptions): Promise<void>;
 }
+
+export abstract class AbstractCachedStorageService extends AbstractStorageService {
+  abstract getBypassCache<T>(key: string, options?: StorageOptions): Promise<T>;
+}

libs/common/src/models/domain/encString.ts

@@ -1,3 +1,5 @@
+import { Jsonify } from "type-fest";
+
 import { IEncrypted } from "@bitwarden/common/interfaces/IEncrypted";
 
 import { CryptoService } from "../../abstractions/crypto.service";
@@ -21,80 +23,9 @@ export class EncString implements IEncrypted {
     mac?: string
   ) {
     if (data != null) {
-      // data and header
-      const encType = encryptedStringOrType as EncryptionType;
-
-      if (iv != null) {
-        this.encryptedString = encType + "." + iv + "|" + data;
-      } else {
-        this.encryptedString = encType + "." + data;
-      }
-
-      // mac
-      if (mac != null) {
-        this.encryptedString += "|" + mac;
-      }
-
-      this.encryptionType = encType;
-      this.data = data;
-      this.iv = iv;
-      this.mac = mac;
-
-      return;
-    }
-
-    this.encryptedString = encryptedStringOrType as string;
-    if (!this.encryptedString) {
-      return;
-    }
-
-    const headerPieces = this.encryptedString.split(".");
-    let encPieces: string[] = null;
-
-    if (headerPieces.length === 2) {
-      try {
-        this.encryptionType = parseInt(headerPieces[0], null);
-        encPieces = headerPieces[1].split("|");
-      } catch (e) {
-        return;
-      }
+      this.initFromData(encryptedStringOrType as EncryptionType, data, iv, mac);
     } else {
-      encPieces = this.encryptedString.split("|");
-      this.encryptionType =
-        encPieces.length === 3
-          ? EncryptionType.AesCbc128_HmacSha256_B64
-          : EncryptionType.AesCbc256_B64;
-    }
-
-    switch (this.encryptionType) {
-      case EncryptionType.AesCbc128_HmacSha256_B64:
-      case EncryptionType.AesCbc256_HmacSha256_B64:
-        if (encPieces.length !== 3) {
-          return;
-        }
-
-        this.iv = encPieces[0];
-        this.data = encPieces[1];
-        this.mac = encPieces[2];
-        break;
-      case EncryptionType.AesCbc256_B64:
-        if (encPieces.length !== 2) {
-          return;
-        }
-
-        this.iv = encPieces[0];
-        this.data = encPieces[1];
-        break;
-      case EncryptionType.Rsa2048_OaepSha256_B64:
-      case EncryptionType.Rsa2048_OaepSha1_B64:
-        if (encPieces.length !== 1) {
-          return;
-        }
-
-        this.data = encPieces[0];
-        break;
-      default:
-        return;
+      this.initFromEncryptedString(encryptedStringOrType as string);
     }
   }
 
@@ -133,4 +64,100 @@ export class EncString implements IEncrypted {
   get dataBytes(): ArrayBuffer {
     return this.data == null ? null : Utils.fromB64ToArray(this.data).buffer;
   }
+
+  toJSON() {
+    return this.encryptedString;
+  }
+
+  static fromJSON(obj: Jsonify<EncString>): EncString {
+    return new EncString(obj);
+  }
+
+  private initFromData(encType: EncryptionType, data: string, iv: string, mac: string) {
+    if (iv != null) {
+      this.encryptedString = encType + "." + iv + "|" + data;
+    } else {
+      this.encryptedString = encType + "." + data;
+    }
+
+    // mac
+    if (mac != null) {
+      this.encryptedString += "|" + mac;
+    }
+
+    this.encryptionType = encType;
+    this.data = data;
+    this.iv = iv;
+    this.mac = mac;
+  }
+
+  private initFromEncryptedString(encryptedString: string) {
+    this.encryptedString = encryptedString as string;
+    if (!this.encryptedString) {
+      return;
+    }
+
+    const { encType, encPieces } = this.parseEncryptedString(this.encryptedString);
+    this.encryptionType = encType;
+
+    switch (encType) {
+      case EncryptionType.AesCbc128_HmacSha256_B64:
+      case EncryptionType.AesCbc256_HmacSha256_B64:
+        if (encPieces.length !== 3) {
+          return;
+        }
+
+        this.iv = encPieces[0];
+        this.data = encPieces[1];
+        this.mac = encPieces[2];
+        break;
+      case EncryptionType.AesCbc256_B64:
+        if (encPieces.length !== 2) {
+          return;
+        }
+
+        this.iv = encPieces[0];
+        this.data = encPieces[1];
+        break;
+      case EncryptionType.Rsa2048_OaepSha256_B64:
+      case EncryptionType.Rsa2048_OaepSha1_B64:
+        if (encPieces.length !== 1) {
+          return;
+        }
+
+        this.data = encPieces[0];
+        break;
+      default:
+        return;
+    }
+  }
+
+  private parseEncryptedString(encryptedString: string): {
+    encType: EncryptionType;
+    encPieces: string[];
+  } {
+    const headerPieces = encryptedString.split(".");
+    let encType: EncryptionType;
+    let encPieces: string[] = null;
+
+    if (headerPieces.length === 2) {
+      try {
+        encType = parseInt(headerPieces[0], null);
+        encPieces = headerPieces[1].split("|");
+      } catch (e) {
+        return;
+      }
+    } else {
+      encPieces = encryptedString.split("|");
+      encType =
+        encPieces.length === 3
+          ? EncryptionType.AesCbc128_HmacSha256_B64
+          : EncryptionType.AesCbc256_B64;
+    }
+
+    return {
+      encType,
+      encPieces,
+    };
+  }
 }

libs/common/src/models/domain/folder.ts

@@ -1,3 +1,5 @@
+import { Jsonify } from "type-fest";
+
 import { FolderData } from "../data/folderData";
 import { FolderView } from "../view/folderView";
 
@@ -37,4 +39,9 @@ export class Folder extends Domain {
       null
     );
   }
+
+  static fromJSON(obj: Jsonify<Folder>) {
+    const revisionDate = obj.revisionDate == null ? null : new Date(obj.revisionDate);
+    return Object.assign(new Folder(), obj, { name: EncString.fromJSON(obj.name), revisionDate });
+  }
 }

libs/common/src/models/view/folderView.ts

@@ -1,3 +1,5 @@
+import { Jsonify } from "type-fest";
+
 import { Folder } from "../domain/folder";
 import { ITreeNodeObject } from "../domain/treeNode";
 
@@ -16,4 +18,9 @@ export class FolderView implements View, ITreeNodeObject {
     this.id = f.id;
     this.revisionDate = f.revisionDate;
   }
+
+  static fromJSON(obj: Jsonify<FolderView>) {
+    const revisionDate = obj.revisionDate == null ? null : new Date(obj.revisionDate);
+    return Object.assign(new FolderView(), obj, { revisionDate });
+  }
 }

libs/common/src/services/folder/folder.service.ts

@@ -13,8 +13,8 @@ import { SymmetricCryptoKey } from "../../models/domain/symmetricCryptoKey";
 import { FolderView } from "../../models/view/folderView";
 
 export class FolderService implements InternalFolderServiceAbstraction {
-  private _folders: BehaviorSubject<Folder[]> = new BehaviorSubject([]);
-  private _folderViews: BehaviorSubject<FolderView[]> = new BehaviorSubject([]);
+  protected _folders: BehaviorSubject<Folder[]> = new BehaviorSubject([]);
+  protected _folderViews: BehaviorSubject<FolderView[]> = new BehaviorSubject([]);
 
   folders$ = this._folders.asObservable();
   folderViews$ = this._folderViews.asObservable();