1 files changed, 91 insertions, 0 deletions
diff --git a/Firebase/Core/Private/FIRComponent.h b/Firebase/Core/Private/FIRComponent.h
new file mode 100644
index 0000000..cb51ee7
--- /dev/null
+++ b/Firebase/Core/Private/FIRComponent.h
@@ -0,0 +1,91 @@
+/*
+ * 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.
+ */
+
+#import <Foundation/Foundation.h>
+
+@class FIRApp;
+@class FIRComponentContainer;
+
+NS_ASSUME_NONNULL_BEGIN
+
+/// Provides a system to clean up cached instances returned from the component system.
+NS_SWIFT_NAME(ComponentLifecycleMaintainer)
+@protocol FIRComponentLifecycleMaintainer
+/// The associated app will be deleted, clean up any resources as they are about to be deallocated.
+- (void)appWillBeDeleted:(FIRApp *)app;
+@end
+
+typedef _Nullable id (^FIRComponentCreationBlock)(FIRComponentContainer *container,
+                                                  BOOL *isCacheable)
+    NS_SWIFT_NAME(ComponentCreationBlock);
+
+@class FIRDependency;
+
+/// Describes the timing of instantiation. Note: new components should default to lazy unless there
+/// is a strong reason to be eager.
+typedef NS_ENUM(NSInteger, FIRInstantiationTiming) {
+  FIRInstantiationTimingLazy,
+  FIRInstantiationTimingAlwaysEager,
+  FIRInstantiationTimingEagerInDefaultApp
+} NS_SWIFT_NAME(InstantiationTiming);
+
+/// A component that can be used from other Firebase SDKs.
+NS_SWIFT_NAME(Component)
+@interface FIRComponent : NSObject
+
+/// The protocol describing functionality provided from the Component.
+@property(nonatomic, strong, readonly) Protocol *protocol;
+
+/// The timing of instantiation.
+@property(nonatomic, readonly) FIRInstantiationTiming instantiationTiming;
+
+/// An array of dependencies for the component.
+@property(nonatomic, copy, readonly) NSArray<FIRDependency *> *dependencies;
+
+/// A block to instantiate an instance of the component with the appropriate dependencies.
+@property(nonatomic, copy, readonly) FIRComponentCreationBlock creationBlock;
+
+// There's an issue with long NS_SWIFT_NAMES that causes compilation to fail, disable clang-format
+// for the next two methods.
+// clang-format off
+
+/// Creates a component with no dependencies that will be lazily initialized.
++ (instancetype)componentWithProtocol:(Protocol *)protocol
+                        creationBlock:(FIRComponentCreationBlock)creationBlock
+NS_SWIFT_NAME(init(_:creationBlock:));
+
+/// Creates a component to be registered with the component container.
+///
+/// @param protocol - The protocol describing functionality provided by the component.
+/// @param instantiationTiming - When the component should be initialized. Use .lazy unless there's
+///                              a good reason to be instantiated earlier.
+/// @param dependencies - Any dependencies the `implementingClass` has, optional or required.
+/// @param creationBlock - A block to instantiate the component with a container, and if
+/// @return A component that can be registered with the component container.
++ (instancetype)componentWithProtocol:(Protocol *)protocol
+                  instantiationTiming:(FIRInstantiationTiming)instantiationTiming
+                         dependencies:(NSArray<FIRDependency *> *)dependencies
+                        creationBlock:(FIRComponentCreationBlock)creationBlock
+NS_SWIFT_NAME(init(_:instantiationTiming:dependencies:creationBlock:));
+
+// clang-format on
+
+/// Unavailable.
+- (instancetype)init NS_UNAVAILABLE;
+
+@end
+
+NS_ASSUME_NONNULL_END