port Firestore Auth module in C++ (#733)

* Implement firestore/auth/user

* add user to project and some fixes

* implement firestore/auth/{credentials_provider,empty_credentials_provider}

* implement firestore/auth/firebase_credentials_provider

* refactoring firebase_credentials_provider and add (disabled but working) unit test

* add auth test to project

* address changes

* small fix to style and project

* fix the firebase_credentials_provider_test

* fix style

* address changes

* revert the change to static mutex_

* remove my custom plist path

* fix style

* address changes

* refactoring FirebaseCredentialsProvider to fix the issue w.r.t. auth global dispatch queue

* add /*force_refresh=*/ tag to bool literal for style purpose

* Use a shared_ptr/weak_ptr handoff on FirebaseCredentialsProvider (#778)

* Revert "refactoring FirebaseCredentialsProvider to fix the issue w.r.t. auth global dispatch queue"

This reverts commit 87175a4146267d403a774f138b85f8d3b532fa4b.

* Use a shared_ptr/weak_ptr handoff on FirebaseCredentialsProvider

This avoids any problems with callsbacks retaining pointers to objects
destroyed by a C++ destructor

1 files changed, 79 insertions, 0 deletions

diff --git a/Firestore/core/src/firebase/firestore/auth/credentials_provider.h b/Firestore/core/src/firebase/firestore/auth/credentials_provider.h
new file mode 100644
index 0000000..2a52c99
--- /dev/null
+++ b/Firestore/core/src/firebase/firestore/auth/credentials_provider.h
@@ -0,0 +1,79 @@
+/*
+ * Copyright 2018 Google
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef FIRESTORE_CORE_SRC_FIREBASE_FIRESTORE_AUTH_CREDENTIALS_PROVIDER_H_
+#define FIRESTORE_CORE_SRC_FIREBASE_FIRESTORE_AUTH_CREDENTIALS_PROVIDER_H_
+
+#include <functional>
+#include <string>
+
+#include "Firestore/core/src/firebase/firestore/auth/token.h"
+#include "Firestore/core/src/firebase/firestore/auth/user.h"
+#include "absl/strings/string_view.h"
+
+namespace firebase {
+namespace firestore {
+namespace auth {
+
+// `TokenErrorListener` is a listener that gets a token or an error.
+// token: An auth token as a string, or nullptr if error occurred.
+// error: The error if one occurred, or else nullptr.
+typedef std::function<void(const Token& token, const absl::string_view error)>
+    TokenListener;
+
+// Listener notified with a User change.
+typedef std::function<void(const User& user)> UserChangeListener;
+
+/**
+ * Provides methods for getting the uid and token for the current user and
+ * listen for changes.
+ */
+class CredentialsProvider {
+ public:
+  CredentialsProvider();
+
+  virtual ~CredentialsProvider();
+
+  /**
+   * Requests token for the current user, optionally forcing a refreshed token
+   * to be fetched.
+   */
+  virtual void GetToken(bool force_refresh, TokenListener completion) = 0;
+
+  /**
+   * Sets the listener to be notified of user changes (sign-in / sign-out). It
+   * is immediately called once with the initial user.
+   *
+   * Call with nullptr to remove previous listener.
+   */
+  virtual void SetUserChangeListener(UserChangeListener listener) = 0;
+
+ protected:
+  /**
+   * A listener to be notified of user changes (sign-in / sign-out). It is
+   * immediately called once with the initial user.
+   *
+   * Note that this block will be called back on an arbitrary thread that is not
+   * the normal Firestore worker thread.
+   */
+  UserChangeListener user_change_listener_;
+};
+
+}  // namespace auth
+}  // namespace firestore
+}  // namespace firebase
+
+#endif  // FIRESTORE_CORE_SRC_FIREBASE_FIRESTORE_AUTH_CREDENTIALS_PROVIDER_H_