firebase-ios-sdk/Firebase/Messaging/Public/FIRMessaging.h

/*
 * Copyright 2017 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>

NS_ASSUME_NONNULL_BEGIN

/**
 *  @related FIRMessaging
 *
 *  The completion handler invoked when the registration token returns.
 *  If the call fails we return the appropriate `error code`, described by
 *  `FIRMessagingError`.
 *
 *  @param FCMToken  The valid registration token returned by FCM.
 *  @param error     The error describing why a token request failed. The error code
 *                   will match a value from the FIRMessagingError enumeration.
 */
typedef void(^FIRMessagingFCMTokenFetchCompletion)(NSString * _Nullable FCMToken,
    NSError * _Nullable error)
    NS_SWIFT_NAME(MessagingFCMTokenFetchCompletion);


/**
 *  @related FIRMessaging
 *
 *  The completion handler invoked when the registration token deletion request is
 *  completed. If the call fails we return the appropriate `error code`, described
 *  by `FIRMessagingError`.
 *
 *  @param error The error describing why a token deletion failed. The error code
 *               will match a value from the FIRMessagingError enumeration.
 */
typedef void(^FIRMessagingDeleteFCMTokenCompletion)(NSError * _Nullable error)
    NS_SWIFT_NAME(MessagingDeleteFCMTokenCompletion);

/**
 *  Callback to invoke once the HTTP call to FIRMessaging backend for updating
 *  subscription finishes.
 *
 *  @param error  The error which occurred while updating the subscription topic
 *                on the FIRMessaging server. This will be nil in case the operation
 *                was successful, or if the operation was cancelled.
 */
typedef void (^FIRMessagingTopicOperationCompletion)(NSError *_Nullable error);

/**
 *  The completion handler invoked once the data connection with FIRMessaging is
 *  established.  The data connection is used to send a continuous stream of
 *  data and all the FIRMessaging data notifications arrive through this connection.
 *  Once the connection is established we invoke the callback with `nil` error.
 *  Correspondingly if we get an error while trying to establish a connection
 *  we invoke the handler with an appropriate error object and do an
 *  exponential backoff to try and connect again unless successful.
 *
 *  @param error The error object if any describing why the data connection
 *               to FIRMessaging failed.
 */
typedef void(^FIRMessagingConnectCompletion)(NSError * __nullable error)
    NS_SWIFT_NAME(MessagingConnectCompletion)
    __deprecated_msg("Please listen for the FIRMessagingConnectionStateChangedNotification "
                     "NSNotification instead.");

#if defined(__IPHONE_10_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0
/**
 *  Notification sent when the upstream message has been delivered
 *  successfully to the server. The notification object will be the messageID
 *  of the successfully delivered message.
 */
FOUNDATION_EXPORT const NSNotificationName FIRMessagingSendSuccessNotification
    NS_SWIFT_NAME(MessagingSendSuccess);

/**
 *  Notification sent when the upstream message was failed to be sent to the
 *  server.  The notification object will be the messageID of the failed
 *  message. The userInfo dictionary will contain the relevant error
 *  information for the failure.
 */
FOUNDATION_EXPORT const NSNotificationName FIRMessagingSendErrorNotification
    NS_SWIFT_NAME(MessagingSendError);

/**
 *  Notification sent when the Firebase messaging server deletes pending
 *  messages due to exceeded storage limits. This may occur, for example, when
 *  the device cannot be reached for an extended period of time.
 *
 *  It is recommended to retrieve any missing messages directly from the
 *  server.
 */
FOUNDATION_EXPORT const NSNotificationName FIRMessagingMessagesDeletedNotification
    NS_SWIFT_NAME(MessagingMessagesDeleted);

/**
 *  Notification sent when Firebase Messaging establishes or disconnects from
 *  an FCM socket connection. You can query the connection state in this
 *  notification by checking the `isDirectChannelEstablished` property of FIRMessaging.
 */
FOUNDATION_EXPORT const NSNotificationName FIRMessagingConnectionStateChangedNotification
    NS_SWIFT_NAME(MessagingConnectionStateChanged);

/**
 *  Notification sent when the FCM registration token has been refreshed. Please use the
 *  FIRMessaging delegate method `messaging:didReceiveRegistrationToken:` to receive current and
 *  updated tokens.
 */
FOUNDATION_EXPORT const NSNotificationName
    FIRMessagingRegistrationTokenRefreshedNotification
    NS_SWIFT_NAME(MessagingRegistrationTokenRefreshed);
#else
/**
 *  Notification sent when the upstream message has been delivered
 *  successfully to the server. The notification object will be the messageID
 *  of the successfully delivered message.
 */
FOUNDATION_EXPORT NSString *const FIRMessagingSendSuccessNotification
    NS_SWIFT_NAME(MessagingSendSuccessNotification);

/**
 *  Notification sent when the upstream message was failed to be sent to the
 *  server.  The notification object will be the messageID of the failed
 *  message. The userInfo dictionary will contain the relevant error
 *  information for the failure.
 */
FOUNDATION_EXPORT NSString *const FIRMessagingSendErrorNotification
    NS_SWIFT_NAME(MessagingSendErrorNotification);

/**
 *  Notification sent when the Firebase messaging server deletes pending
 *  messages due to exceeded storage limits. This may occur, for example, when
 *  the device cannot be reached for an extended period of time.
 *
 *  It is recommended to retrieve any missing messages directly from the
 *  server.
 */
FOUNDATION_EXPORT NSString *const FIRMessagingMessagesDeletedNotification
    NS_SWIFT_NAME(MessagingMessagesDeletedNotification);

/**
 *  Notification sent when Firebase Messaging establishes or disconnects from
 *  an FCM socket connection. You can query the connection state in this
 *  notification by checking the `isDirectChannelEstablished` property of FIRMessaging.
 */
FOUNDATION_EXPORT NSString *const FIRMessagingConnectionStateChangedNotification
    NS_SWIFT_NAME(MessagingConnectionStateChangedNotification);

/**
 *  Notification sent when the FCM registration token has been refreshed. Please use the
 *  FIRMessaging delegate method `messaging:didReceiveRegistrationToken:` to receive current and
 *  updated tokens.
 */
FOUNDATION_EXPORT NSString *const FIRMessagingRegistrationTokenRefreshedNotification
    NS_SWIFT_NAME(MessagingRegistrationTokenRefreshedNotification);
#endif  // defined(__IPHONE_10_0) && __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_10_0

/**
 *  @enum FIRMessagingError
 */
typedef NS_ENUM(NSUInteger, FIRMessagingError) {
  /// Unknown error.
  FIRMessagingErrorUnknown = 0,

  /// FIRMessaging couldn't validate request from this client.
  FIRMessagingErrorAuthentication = 1,

  /// InstanceID service cannot be accessed.
  FIRMessagingErrorNoAccess = 2,

  /// Request to InstanceID backend timed out.
  FIRMessagingErrorTimeout = 3,

  /// No network available to reach the servers.
  FIRMessagingErrorNetwork = 4,

  /// Another similar operation in progress, bailing this one.
  FIRMessagingErrorOperationInProgress = 5,

  /// Some parameters of the request were invalid.
  FIRMessagingErrorInvalidRequest = 7,

  /// Topic name is invalid for subscription/unsubscription.
  FIRMessagingErrorInvalidTopicName = 8,

} NS_SWIFT_NAME(MessagingError);

/// Status for the downstream message received by the app.
typedef NS_ENUM(NSInteger, FIRMessagingMessageStatus) {
  /// Unknown status.
  FIRMessagingMessageStatusUnknown,
  /// New downstream message received by the app.
  FIRMessagingMessageStatusNew,
} NS_SWIFT_NAME(MessagingMessageStatus);

/**
 *  The APNS token type for the app. If the token type is set to `UNKNOWN`
 *  Firebase Messaging will implicitly try to figure out what the actual token type
 *  is from the provisioning profile.
 *  Unless you really need to specify the type, you should use the `APNSToken`
 *  property instead.
 */
typedef NS_ENUM(NSInteger, FIRMessagingAPNSTokenType) {
  /// Unknown token type.
  FIRMessagingAPNSTokenTypeUnknown,
  /// Sandbox token type.
  FIRMessagingAPNSTokenTypeSandbox,
  /// Production token type.
  FIRMessagingAPNSTokenTypeProd,
} NS_SWIFT_NAME(MessagingAPNSTokenType);

/// Information about a downstream message received by the app.
NS_SWIFT_NAME(MessagingMessageInfo)
@interface FIRMessagingMessageInfo : NSObject

/// The status of the downstream message
@property(nonatomic, readonly, assign) FIRMessagingMessageStatus status;

@end

/**
 * A remote data message received by the app via FCM (not just the APNs interface).
 *
 * This is only for devices running iOS 10 or above. To support devices running iOS 9 or below, use
 * the local and remote notifications handlers defined in UIApplicationDelegate protocol.
 */
NS_SWIFT_NAME(MessagingRemoteMessage)
@interface FIRMessagingRemoteMessage : NSObject

/// The message ID of downstream message.
@property(nonatomic, readonly, copy) NSString *messageID;
/// The downstream message received by the application.
@property(nonatomic, readonly, strong) NSDictionary *appData;

@end

@class FIRMessaging;
/**
 * A protocol to handle token update or data message delivery from FCM.
 *
 */
NS_SWIFT_NAME(MessagingDelegate)
@protocol FIRMessagingDelegate <NSObject>

@optional
/// This method will be called once a token is available, or has been refreshed. Typically it
/// will be called once per app start, but may be called more often, if token is invalidated or
/// updated. In this method, you should perform operations such as:
///
/// * Uploading the FCM token to your application server, so targeted notifications can be sent.
///
/// * Subscribing to any topics.
- (void)messaging:(FIRMessaging *)messaging
    didReceiveRegistrationToken:(NSString *)fcmToken
    NS_SWIFT_NAME(messaging(_:didReceiveRegistrationToken:));

/// This method is called on iOS 10+ devices to handle data messages received via FCM
/// direct channel (not via APNS). For iOS 9 and below, the direct channel data message
/// is handled by the UIApplicationDelegate's -application:didReceiveRemoteNotification: method.
/// You can enable all direct channel data messages to be delivered in FIRMessagingDelegate
/// by setting the flag `useMessagingDelegateForDirectMessages` to true.
- (void)messaging:(FIRMessaging *)messaging
    didReceiveMessage:(FIRMessagingRemoteMessage *)remoteMessage
    NS_SWIFT_NAME(messaging(_:didReceive:))
    __IOS_AVAILABLE(10.0);

@end

/**
 *  Firebase Messaging lets you reliably deliver messages at no cost.
 *
 *  To send or receive messages, the app must get a
 *  registration token from FIRInstanceID. This token authorizes an
 *  app server to send messages to an app instance.
 *
 *  In order to receive FIRMessaging messages, declare
 *  `application:didReceiveRemoteNotification::fetchCompletionHandler:`.
 */
NS_SWIFT_NAME(Messaging)
@interface FIRMessaging : NSObject

/**
 * Delegate to handle FCM token refreshes, and remote data messages received via FCM direct channel.
 */
@property(nonatomic, weak, nullable) id<FIRMessagingDelegate> delegate;

/**
 *  When set to `YES`, Firebase Messaging will automatically establish a socket-based, direct
 *  channel to the FCM server. Enable this only if you are sending upstream messages or
 *  receiving non-APNS, data-only messages in foregrounded apps.
 *  Default is `NO`.
 */
@property(nonatomic) BOOL shouldEstablishDirectChannel;

/**
 *  Returns `YES` if the direct channel to the FCM server is active, and `NO` otherwise.
 */
@property(nonatomic, readonly) BOOL isDirectChannelEstablished;

/*
 * Whether direct channel message should only use FIRMessagingDelegate messaging(_:didReceive:)
 * for message delivery callback. The default value is false. If you need to change
 * the default, set FirebaseMessagingUseMessagingDelegateForDirectChannel to true in
 * your application’s Info.plist.
 *
 * If false, the message via direct channel for iOS 9 and below is still delivered in
 * `-UIApplicationDelegate application(_:didReceiveRemoteNotification:fetchCompletionHandler:)`,
 * and the FIRMessagingRemoteMessage object and its associated data will be unavailable.
 * For iOS 10 and above, it is still delivered in `FIRMessagingDelegate messaging(_:didReceive:)`.
 *
 * If true, the data message sent by direct channel will be delivered via
 * `FIRMessagingDelegate messaging(_:didReceive:)` and across all iOS versions.
 */
@property(nonatomic, assign) BOOL useMessagingDelegateForDirectChannel;

/**
 *  FIRMessaging
 *
 *  @return An instance of FIRMessaging.
 */
+ (instancetype)messaging NS_SWIFT_NAME(messaging());

/**
 *  Unavailable. Use +messaging instead.
 */
- (instancetype)init __attribute__((unavailable("Use +messaging instead.")));

#pragma mark - APNS

/**
 *  This property is used to set the APNS Token received by the application delegate.
 *
 *  FIRMessaging uses method swizzling to ensure that the APNS token is set
 *  automatically. However, if you have disabled swizzling by setting
 *  `FirebaseAppDelegateProxyEnabled` to `NO` in your app's
 *  Info.plist, you should manually set the APNS token in your application
 *  delegate's `-application:didRegisterForRemoteNotificationsWithDeviceToken:`
 *  method.
 *
 *  If you would like to set the type of the APNS token, rather than relying on
 *  automatic detection, see: `-setAPNSToken:type:`.
 */
@property(nonatomic, copy, nullable) NSData *APNSToken NS_SWIFT_NAME(apnsToken);

/**
 *  Set APNS token for the application. This APNS token will be used to register
 *  with Firebase Messaging using `FCMToken` or
 *  `tokenWithAuthorizedEntity:scope:options:handler`.
 *
 *  @param apnsToken The APNS token for the application.
 *  @param type  The type of APNS token. Debug builds should use
 *  FIRMessagingAPNSTokenTypeSandbox. Alternatively, you can supply
 *  FIRMessagingAPNSTokenTypeUnknown to have the type automatically
 *  detected based on your provisioning profile.
 */
- (void)setAPNSToken:(NSData *)apnsToken type:(FIRMessagingAPNSTokenType)type;

#pragma mark - FCM Tokens

/**
 * Is Firebase Messaging token auto generation enabled?  If this flag is disabled,
 * Firebase Messaging will not generate token automatically for message delivery.
 *
 * If this flag is disabled, Firebase Messaging does not generate new tokens automatically for
 * message delivery. If this flag is enabled, FCM generates a registration token on application
 * start when there is no existing valid token. FCM also generates a new token when an existing
 * token is deleted.
 *
 * This setting is persisted, and is applied on future
 * invocations of your application.  Once explicitly set, it overrides any
 * settings in your Info.plist.
 *
 * By default, FCM automatic initialization is enabled.  If you need to change the
 * default (for example, because you want to prompt the user before getting token)
 * set FirebaseMessagingAutoInitEnabled to false in your application's Info.plist.
 */
@property(nonatomic, assign, getter=isAutoInitEnabled) BOOL autoInitEnabled;

/**
 *  The FCM token is used to identify this device so that FCM can send notifications to it.
 *  It is associated with your APNS token when the APNS token is supplied, so that sending
 *  messages to the FCM token will be delivered over APNS.
 *
 *  The FCM token is sometimes refreshed automatically. In your FIRMessaging delegate, the
 *  delegate method `messaging:didReceiveRegistrationToken:` will be called once a token is
 *  available, or has been refreshed. Typically it should be called once per app start, but
 *  may be called more often, if token is invalidated or updated.
 *
 *  Once you have an FCM token, you should send it to your application server, so it can use
 *  the FCM token to send notifications to your device.
 */
@property(nonatomic, readonly, nullable) NSString *FCMToken NS_SWIFT_NAME(fcmToken);


/**
 *  Retrieves an FCM registration token for a particular Sender ID. This can be used to allow
 *  multiple senders to send notifications to the same device. By providing a different Sender
 *  ID than your default when fetching a token, you can create a new FCM token which you can
 *  give to a different sender. Both tokens will deliver notifications to your device, and you
 *  can revoke a token when you need to.
 *
 *  This registration token is not cached by FIRMessaging. FIRMessaging should have an APNS
 *  token set before calling this to ensure that notifications can be delivered via APNS using
 *  this FCM token. You may re-retrieve the FCM token once you have the APNS token set, to
 *  associate it with the FCM token. The default FCM token is automatically associated with
 *  the APNS token, if the APNS token data is available.
 *
 *  @param senderID The Sender ID for a particular Firebase project.
 *  @param completion The completion handler to handle the token request.
 */
- (void)retrieveFCMTokenForSenderID:(NSString *)senderID
                         completion:(FIRMessagingFCMTokenFetchCompletion)completion
    NS_SWIFT_NAME(retrieveFCMToken(forSenderID:completion:));


/**
 *  Invalidates an FCM token for a particular Sender ID. That Sender ID cannot no longer send
 *  notifications to that FCM token.
 *
 *  @param senderID The senderID for a particular Firebase project.
 *  @param completion The completion handler to handle the token deletion.
 */
- (void)deleteFCMTokenForSenderID:(NSString *)senderID
                       completion:(FIRMessagingDeleteFCMTokenCompletion)completion
    NS_SWIFT_NAME(deleteFCMToken(forSenderID:completion:));


#pragma mark - FCM Direct Channel

/**
 *  Create a FIRMessaging data connection which will be used to send the data notifications
 *  sent by your server. It will also be used to send ACKS and other messages based
 *  on the FIRMessaging ACKS and other messages based  on the FIRMessaging protocol.
 *
 *
 *  @param handler  The handler to be invoked once the connection is established.
 *                  If the connection fails we invoke the handler with an
 *                  appropriate error code letting you know why it failed. At
 *                  the same time, FIRMessaging performs exponential backoff to retry
 *                  establishing a connection and invoke the handler when successful.
 */
- (void)connectWithCompletion:(FIRMessagingConnectCompletion)handler
    NS_SWIFT_NAME(connect(handler:))
    __deprecated_msg("Please use the shouldEstablishDirectChannel property instead.");

/**
 *  Disconnect the current FIRMessaging data connection. This stops any attempts to
 *  connect to FIRMessaging. Calling this on an already disconnected client is a no-op.
 *
 *  Call this before `teardown` when your app is going to the background.
 *  Since the FIRMessaging connection won't be allowed to live when in the background, it is
 *  prudent to close the connection.
 */
- (void)disconnect
      __deprecated_msg("Please use the shouldEstablishDirectChannel property instead.");

#pragma mark - Topics

/**
 *  Asynchronously subscribes to a topic.
 *
 *  @param topic The name of the topic, for example, @"sports".
 */
- (void)subscribeToTopic:(NSString *)topic NS_SWIFT_NAME(subscribe(toTopic:));

/**
 *  Asynchronously subscribe to the provided topic, retrying on failure.
 *
 *  @param topic       The topic name to subscribe to, for example, @"sports".
 *  @param completion  The completion that is invoked once the subscribe call ends.
 *                     In case of success, nil error is returned. Otherwise, an
 *                     appropriate error object is returned.
 */
- (void)subscribeToTopic:(nonnull NSString *)topic
              completion:(nullable FIRMessagingTopicOperationCompletion)completion;

/**
 *  Asynchronously unsubscribe from a topic.
 *
 *  @param topic The name of the topic, for example @"sports".
 */
- (void)unsubscribeFromTopic:(NSString *)topic NS_SWIFT_NAME(unsubscribe(fromTopic:));

/**
 *  Asynchronously unsubscribe from the provided topic, retrying on failure.
 *
 *  @param topic       The topic name to unsubscribe from, for example @"sports".
 *  @param completion  The completion that is invoked once the unsubscribe call ends.
 *                     In case of success, nil error is returned. Otherwise, an
 *                     appropriate error object is returned.
 */
- (void)unsubscribeFromTopic:(nonnull NSString *)topic
                  completion:(nullable FIRMessagingTopicOperationCompletion)completion;

#pragma mark - Upstream

/**
 *  Sends an upstream ("device to cloud") message.
 *
 *  The message is queued if we don't have an active connection.
 *  You can only use the upstream feature if your FCM implementation
 *  uses the XMPP server protocol.
 *
 *  @param message      Key/Value pairs to be sent. Values must be String, any
 *                      other type will be ignored.
 *  @param receiver     A string identifying the receiver of the message. For FCM
 *                      project IDs the value is `SENDER_ID@gcm.googleapis.com`.
 *  @param messageID    The ID of the message. This is generated by the application. It
 *                      must be unique for each message generated by this application.
 *                      It allows error callbacks and debugging, to uniquely identify
 *                      each message.
 *  @param ttl          The time to live for the message. In case we aren't able to
 *                      send the message before the TTL expires we will send you a
 *                      callback. If 0, we'll attempt to send immediately and return
 *                      an error if we're not connected.  Otherwise, the message will
 *                      be queued.  As for server-side messages, we don't return an error
 *                      if the message has been dropped because of TTL; this can happen
 *                      on the server side, and it would require extra communication.
 */
- (void)sendMessage:(NSDictionary *)message
                 to:(NSString *)receiver
      withMessageID:(NSString *)messageID
         timeToLive:(int64_t)ttl;

#pragma mark - Analytics

/**
 *  Use this to track message delivery and analytics for messages, typically
 *  when you receive a notification in `application:didReceiveRemoteNotification:`.
 *  However, you only need to call this if you set the `FirebaseAppDelegateProxyEnabled`
 *  flag to `NO` in your Info.plist. If `FirebaseAppDelegateProxyEnabled` is either missing
 *  or set to `YES` in your Info.plist, the library will call this automatically.
 *
 *  @param message The downstream message received by the application.
 *
 *  @return Information about the downstream message.
 */
- (FIRMessagingMessageInfo *)appDidReceiveMessage:(NSDictionary *)message;

@end

NS_ASSUME_NONNULL_END