add UseEmulator api to auth (#1437)

* add auth emulator support

* fix ios number parse

* update the documentation part

* reduce lint warning

* more lint warnings

* code format

* use environment to decide using emulator or not

* fix a typo

* add readme entry for FirebaseApp.GetApps()

* update for review comment

* add missing `

* make json request always do restrict json

* add readme info

* prepare for review

* some minor tweak

* code format

* update review comments

* update the unit test after request json change

* remove platform logging v1 code

* add useEmulator api

* test with emulator

* clean up for review

* tweak for review

* update with comments

* put back necessary heartbeat blocks

---------

Co-authored-by: Cynthia Jiang <cynthiajiang@google.com>

Author: cynthiajoan

auth/src/android/auth_android.cc

@@ -188,11 +188,19 @@ void UpdateCurrentUser(AuthData* auth_data) {
   }
 }
 
+void SetEmulatorJni(AuthData* auth_data, const char* host, uint32_t port) {
+  JNIEnv* env = Env(auth_data);
+
+  jstring j_host = env->NewStringUTF(host);
+  env->CallVoidMethod(AuthImpl(auth_data),
+                      auth::GetMethodId(auth::kUseEmulator), j_host, port);
+  env->DeleteLocalRef(j_host);
+  firebase::util::CheckAndClearJniExceptions(env);
+}
+
 const char* const kEmulatorLocalHost = "10.0.2.2";
 const char* const kEmulatorPort = "9099";
 void CheckEmulator(AuthData* auth_data) {
-  JNIEnv* env = Env(auth_data);
-
   // Use emulator as long as this env variable is set, regardless its value.
   if (std::getenv("USE_AUTH_EMULATOR") == nullptr) {
     LogInfo("Using Auth Prod for testing.");
@@ -207,12 +215,7 @@ void CheckEmulator(AuthData* auth_data) {
   if (std::getenv("AUTH_EMULATOR_PORT") != nullptr) {
     port = std::stoi(std::getenv("AUTH_EMULATOR_PORT"));
   }
-
-  jstring j_host = env->NewStringUTF(kEmulatorLocalHost);
-  env->CallVoidMethod(AuthImpl(auth_data),
-                      auth::GetMethodId(auth::kUseEmulator), j_host, port);
-  env->DeleteLocalRef(j_host);
-  firebase::util::CheckAndClearJniExceptions(env);
+  SetEmulatorJni(auth_data, kEmulatorLocalHost, port);
 }
 
 // Release cached Java classes.
@@ -828,6 +831,10 @@ Future<void> Auth::SendPasswordResetEmail(const char* email) {
   return MakeFuture(&futures, handle);
 }
 
+void Auth::UseEmulator(std::string host, uint32_t port) {
+  SetEmulatorJni(auth_data_, host.c_str(), port);
+}
+
 // Not implemented for Android.
 void EnableTokenAutoRefresh(AuthData* auth_data) {}
 void DisableTokenAutoRefresh(AuthData* auth_data) {}

auth/src/desktop/auth_desktop.cc

@@ -715,6 +715,14 @@ void Auth::UseAppLanguage() {
   auth_impl->language_code.assign(empty_string);
 }
 
+void Auth::UseEmulator(std::string host, uint32_t port) {
+  auto auth_impl = static_cast<AuthImpl*>(auth_data_->auth_impl);
+  auth_impl->assigned_emulator_url = "";
+  auth_impl->assigned_emulator_url.append(host);
+  auth_impl->assigned_emulator_url.append(":");
+  auth_impl->assigned_emulator_url.append(std::to_string(port));
+}
+
 void InitializeTokenRefresher(AuthData* auth_data) {
   auto auth_impl = static_cast<AuthImpl*>(auth_data->auth_impl);
   auth_impl->token_refresh_thread.Initialize(auth_data);

auth/src/desktop/auth_desktop.h

@@ -188,6 +188,8 @@ struct AuthImpl {
   // The current user language code. This can be set to the app’s current
   // language by calling SetLanguageCode.
   std::string language_code;
+
+  std::string assigned_emulator_url;
 };
 
 // Constant, describing how often we automatically fetch a new auth token.

auth/src/desktop/rpcs/auth_request.cc

@@ -23,6 +23,8 @@
 #include "app/src/heartbeat/heartbeat_controller_desktop.h"
 #include "app/src/include/firebase/app.h"
 #include "app/src/include/firebase/internal/mutex.h"
+#include "auth/src/desktop/auth_desktop.h"
+#include "auth/src/include/firebase/auth.h"
 #include "firebase/log.h"
 
 namespace firebase {
@@ -33,39 +35,9 @@ const char* kHeaderFirebaseLocale = "X-Firebase-Locale";
 
 AuthRequest::AuthRequest(::firebase::App& app, const char* schema,
                          bool deliver_heartbeat)
-    : RequestJson(schema) {
-  // The user agent strings are cached in static variables here to avoid
-  // dependencies upon other parts of this library.  This complication is due to
-  // the way the tests are currently configured where each library has minimal
-  // dependencies.
+    : RequestJson(schema), app(app) {
+  CheckEnvEmulator();
 
-  CheckEmulator();
-  static std::string auth_user_agent;           // NOLINT
-  static std::string extended_auth_user_agent;  // NOLINT
-  static Mutex* user_agent_mutex = new Mutex();
-  MutexLock lock(*user_agent_mutex);
-  if (auth_user_agent.empty()) {
-    std::string sdk;
-    std::string version;
-    app_common::GetOuterMostSdkAndVersion(&sdk, &version);
-    // Set the user agent similar to the iOS SDK.  Format:
-    // FirebaseAuth.<platform>/<sdk_version>
-    assert(!(sdk.empty() || version.empty()));
-    std::string sdk_type(sdk.substr(sizeof(FIREBASE_USER_AGENT_PREFIX) - 1));
-    auth_user_agent = std::string("FirebaseAuth.") + sdk_type + "/" + version;
-    // Generage the extended header to set the format specified by b/28531026
-    // and b/64693042 to include the platform and framework.
-    // <environment>/<sdk_implementation>/<sdk_version>/<framework>
-    // where <framework> is '(FirebaseCore|FirebaseUI)'.
-    extended_auth_user_agent = std::string(app_common::kOperatingSystem) + "/" +
-                               sdk + "/" + version + "/" + "FirebaseCore-" +
-                               sdk_type;
-  }
-  // TODO(b/244643516): Remove the User-Agent and X-Client-Version headers.
-  if (!auth_user_agent.empty()) {
-    add_header("User-Agent", auth_user_agent.c_str());
-    add_header("X-Client-Version", extended_auth_user_agent.c_str());
-  }
   if (deliver_heartbeat) {
     std::shared_ptr<heartbeat::HeartbeatController> heartbeat_controller =
         app.GetHeartbeatController();
@@ -81,6 +53,17 @@ AuthRequest::AuthRequest(::firebase::App& app, const char* schema,
 }
 
 std::string AuthRequest::GetUrl() {
+  std::string emulator_url;
+  Auth* auth_ptr = Auth::GetAuth(&app);
+  std::string assigned_emulator_url =
+      static_cast<AuthImpl*>(auth_ptr->auth_data_->auth_impl)
+          ->assigned_emulator_url;
+  if (assigned_emulator_url.empty()) {
+    emulator_url = env_emulator_url;
+  } else {
+    emulator_url = assigned_emulator_url;
+  }
+
   if (emulator_url.empty()) {
     std::string url(kHttps);
     url += kServerURL;
@@ -94,25 +77,26 @@ std::string AuthRequest::GetUrl() {
   }
 }
 
-void AuthRequest::CheckEmulator() {
-  if (!emulator_url.empty()) {
-    LogInfo("Emulator Url already set: %s", emulator_url.c_str());
+void AuthRequest::CheckEnvEmulator() {
+  if (!env_emulator_url.empty()) {
+    LogInfo("Environment Emulator Url already set: %s",
+            env_emulator_url.c_str());
     return;
   }
+
   // Use emulator as long as this env variable is set, regardless its value.
   if (std::getenv("USE_AUTH_EMULATOR") == nullptr) {
-    LogInfo("Using Auth Prod for testing.");
+    LogInfo("USE_AUTH_EMULATOR not set.");
     return;
   }
-  LogInfo("Using Auth Emulator.");
-  emulator_url.append(kEmulatorLocalHost);
-  emulator_url.append(":");
+  env_emulator_url.append(kEmulatorLocalHost);
+  env_emulator_url.append(":");
   // Use AUTH_EMULATOR_PORT if it is set to non empty string,
   // otherwise use the default port.
   if (std::getenv("AUTH_EMULATOR_PORT") == nullptr) {
-    emulator_url.append(kEmulatorPort);
+    env_emulator_url.append(kEmulatorPort);
   } else {
-    emulator_url.append(std::getenv("AUTH_EMULATOR_PORT"));
+    env_emulator_url.append(std::getenv("AUTH_EMULATOR_PORT"));
   }
 }
 

auth/src/desktop/rpcs/auth_request.h

@@ -55,8 +55,9 @@ class AuthRequest
   std::string GetUrl();
 
  private:
-  void CheckEmulator();
-  std::string emulator_url;
+  void CheckEnvEmulator();
+  std::string env_emulator_url;
+  ::firebase::App& app;
 };
 
 }  // namespace auth

auth/src/include/firebase/auth.h

@@ -45,6 +45,7 @@ struct AuthData;
 class AuthStateListener;
 class IdTokenListener;
 class PhoneAuthProvider;
+class AuthRequest;
 struct AuthCompletionHandle;
 struct AuthResultCompletionHandle;
 class FederatedAuthProvider;
@@ -631,6 +632,14 @@ class Auth {
   void RemoveIdTokenListener(IdTokenListener* listener);
 #endif  // not SWIG
 
+#if !defined(DOXYGEN) && !defined(SWIG)
+  ///
+  /// Modify this Auth instance to communicate with the Firebase Authentication
+  /// emulator.
+  ///
+  void UseEmulator(std::string host, uint32_t port);
+#endif  //! defined(DOXYGEN), to hide the api from public documentation.
+
   /// Gets the App this auth object is connected to.
   App& app();
 
@@ -653,6 +662,7 @@ class Auth {
   /// @cond FIREBASE_APP_INTERNAL
   friend class ::firebase::App;
   friend class ::firebase::auth::PhoneAuthProvider;
+  friend class ::firebase::auth::AuthRequest;
   friend class IdTokenRefreshListener;
   friend class IdTokenRefreshThread;
   friend class UserDataPersist;

auth/src/ios/auth_ios.mm

@@ -157,6 +157,11 @@ void UpdateCurrentUser(AuthData *auth_data) {
   SetUserImpl(auth_data, user);
 }
 
+void SetEmulatorJni(AuthData *auth_data, const char *host, uint32_t port) {
+  NSUInteger ns_port = port;
+  [AuthImpl(auth_data) useEmulatorWithHost:@(host) port:ns_port];
+}
+
 void CheckEmulator(AuthData *auth_data) {
   // Use emulator as long as this env variable is set, regardless its value.
   if (std::getenv("USE_AUTH_EMULATOR") == nullptr) {
@@ -171,8 +176,7 @@ void CheckEmulator(AuthData *auth_data) {
     port = std::stoi(std::getenv("AUTH_EMULATOR_PORT"));
   }
 
-  NSUInteger ns_port = port;
-  [AuthImpl(auth_data) useEmulatorWithHost:@(kEmulatorLocalHost) port:ns_port];
+  SetEmulatorJni(auth_data, kEmulatorLocalHost, port);
 }
 
 // Platform-specific method to initialize AuthData.
@@ -699,6 +703,10 @@ void SignInResultCallback(FIRAuthDataResult *_Nullable auth_result, NSError *_Nu
   return MakeFuture(&futures, handle);
 }
 
+void Auth::UseEmulator(std::string host, uint32_t port) {
+  SetEmulatorJni(auth_data_, host.c_str(), port);
+}
+
 // Remap iOS SDK errors reported by the UIDelegate. While these errors seem like
 // user interaction errors, they are actually caused by bad provider ids.
 NSError *RemapBadProviderIDErrors(NSError *_Nonnull error) {