Lacros: Add AccountManagerObserver interface

Add a Mojo interface - AccountManagerObserver - for ash-chrome to send
account update notifications to lacros-chrome.

Bug: 1117478
Test: unit_tests --gtest_filter="*AccountManagerAshTest*"
Change-Id: I986676d3a635bdc3e50abd9d7489ea0645c2286d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2453259
Commit-Queue: Kush Sinha <sinhak@chromium.org>
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#815175}

chrome/browser/chromeos/crosapi/account_manager_ash.cc

@@ -6,7 +6,9 @@
 
 #include <utility>
 
+#include "base/callback.h"
 #include "chromeos/components/account_manager/account_manager.h"
+#include "mojo/public/cpp/bindings/remote.h"
 
 namespace crosapi {
 
@@ -23,4 +25,11 @@ void AccountManagerAsh::IsInitialized(IsInitializedCallback callback) {
   std::move(callback).Run(account_manager_->IsInitialized());
 }
 
+void AccountManagerAsh::AddObserver(AddObserverCallback callback) {
+  mojo::Remote<mojom::AccountManagerObserver> remote;
+  auto receiver = remote.BindNewPipeAndPassReceiver();
+  observers_.Add(std::move(remote));
+  std::move(callback).Run(std::move(receiver));
+}
+
 }  // namespace crosapi

chrome/browser/chromeos/crosapi/account_manager_ash.h

@@ -8,6 +8,7 @@
 #include "chromeos/crosapi/mojom/account_manager.mojom.h"
 #include "mojo/public/cpp/bindings/pending_receiver.h"
 #include "mojo/public/cpp/bindings/receiver.h"
+#include "mojo/public/cpp/bindings/remote_set.h"
 
 namespace chromeos {
 class AccountManager;
@@ -28,10 +29,14 @@ class AccountManagerAsh : public mojom::AccountManager {
 
   // crosapi::mojom::AccountManager:
   void IsInitialized(IsInitializedCallback callback) override;
+  void AddObserver(AddObserverCallback callback) override;
 
  private:
+  friend class AccountManagerAshTest;
+
   chromeos::AccountManager* const account_manager_;
   mojo::Receiver<mojom::AccountManager> receiver_;
+  mojo::RemoteSet<mojom::AccountManagerObserver> observers_;
 };
 
 }  // namespace crosapi

chrome/browser/chromeos/crosapi/account_manager_ash_unittest.cc

@@ -4,6 +4,7 @@
 
 #include "chrome/browser/chromeos/crosapi/account_manager_ash.h"
 
+#include <cstddef>
 #include <memory>
 
 #include "base/run_loop.h"
@@ -11,6 +12,8 @@
 #include "base/test/task_environment.h"
 #include "chromeos/components/account_manager/account_manager.h"
 #include "chromeos/crosapi/mojom/account_manager.mojom-test-utils.h"
+#include "chromeos/crosapi/mojom/account_manager.mojom.h"
+#include "mojo/public/cpp/bindings/pending_receiver.h"
 #include "mojo/public/cpp/bindings/remote.h"
 #include "services/network/public/cpp/weak_wrapper_shared_url_loader_factory.h"
 #include "services/network/test/test_url_loader_factory.h"
@@ -34,6 +37,8 @@ class AccountManagerAshTest : public ::testing::Test {
             account_manager_ash_.get());
   }
 
+  void RunAllPendingTasks() { task_environment_.RunUntilIdle(); }
+
   // Returns |true| if initialization was successful.
   bool InitializeAccountManager() {
     base::RunLoop run_loop;
@@ -43,6 +48,8 @@ class AccountManagerAshTest : public ::testing::Test {
     return account_manager_.IsInitialized();
   }
 
+  size_t GetNumObservers() { return account_manager_ash_->observers_.size(); }
+
   mojom::AccountManagerAsyncWaiter* account_manager_async_waiter() {
     return account_manager_async_waiter_.get();
   }
@@ -75,4 +82,18 @@ TEST_F(AccountManagerAshTest,
   EXPECT_TRUE(is_initialized);
 }
 
+// Test that lacros remotes do not leak.
+TEST_F(AccountManagerAshTest,
+       LacrosRemotesAreAutomaticallyRemovedOnConnectionClose) {
+  EXPECT_EQ(0, GetNumObservers());
+  {
+    mojo::PendingReceiver<mojom::AccountManagerObserver> receiver;
+    account_manager_async_waiter()->AddObserver(&receiver);
+    EXPECT_EQ(1, GetNumObservers());
+  }
+  // Wait for the disconnect handler to be called.
+  RunAllPendingTasks();
+  EXPECT_EQ(0, GetNumObservers());
+}
+
 }  // namespace crosapi

chromeos/crosapi/mojom/account_manager.mojom

@@ -4,6 +4,58 @@
 
 module crosapi.mojom;
 
+// Types of accounts which can be stored in Account Manager.
+// This must be kept in sync with
+// //chromeos/components/account_manager/tokens.proto
+[Stable, Extensible]
+enum AccountType {
+  kUnspecified = 0,
+  kGaia = 1,
+  kActiveDirectory = 2,
+};
+
+// Uniquely identifies an account in Account Manager.
+[Stable]
+struct AccountKey {
+  // |id| is obfuscated Gaia id for Gaia accounts.
+  // |id| is the object GUID for Microsoft Active Directory accounts.
+  string id@0;
+
+  // Type of the account - such as Gaia, or Microsoft Active Directory.
+  AccountType account_type@1;
+};
+
+// Information about an account in Account Manager.
+[Stable]
+struct Account {
+  // A unique identifier for this account.
+  AccountKey key@0;
+
+  // The raw, un-canonicalized email id (The.Rock@gmail.com, as opposed to
+  // therock@gmail.com) for this account.
+  string raw_email@1;
+};
+
+// Interface for observers of Chrome OS Account Manager.
+// This interface is implemented by lacros-chrome, and is used by ash-chrome to
+// send account update notifications.
+[Stable]
+interface AccountManagerObserver {
+  // Called when the token for |account| is updated/inserted.
+  // Note: Observers which register with |AccountManager| before its
+  // initialization is complete will get notified when |AccountManager| is fully
+  // initialized.
+  // Note: Observers which register with |AccountManager| after its
+  // initialization is complete will not get an immediate
+  // notification-on-registration.
+  OnTokenUpserted@0(Account account);
+
+  // Called when an account has been removed from Account Manager.
+  // Note: Observers that may have cached access tokens for |account| must clear
+  // their cache entry for this |account| on receiving this callback.
+  OnAccountRemoved@1(Account account);
+};
+
 // Interface for Chrome OS Account Manager.
 // Chrome OS Account Manager is the source of truth for accounts on Chrome OS -
 // including ARC, and Chrome content area. It supports Google accounts and
@@ -12,9 +64,21 @@ module crosapi.mojom;
 // query accounts residing in the Chrome OS Account Manager.
 // ARC++ uses components/arc/mojom/auth.mojom to talk to the Chrome OS Account
 // Manager.
+//
+// Next version: 2
+// Next method id: 2
 [Stable]
 interface AccountManager {
   // Returns |true| if Chrome OS Account Manager has been fully initialized, and
   // |false| otherwise.
   IsInitialized@0() => (bool is_initialized);
+
+  // Creates and returns a new receiver for |AccountManagerObserver|.
+  // This API is supposed to be called by lacros-chrome, fairly early during its
+  // initialization, to receive updates related to accounts stored in Account
+  // Manager.
+  // The connection, and the corresponding remote, is destroyed when |receiver|
+  // is destroyed. This will happen automatically when lacros is shut down.
+  [MinVersion = 1]
+  AddObserver@1() => (pending_receiver<AccountManagerObserver> receiver);
 };