Apple 플랫폼에서 커스텀 제공자로 앱 체크 사용 시작하기

class YourCustomAppCheckProvider: NSObject, AppCheckProvider {
  var app: FirebaseApp

  init(withFirebaseApp app: FirebaseApp) {
    self.app = app
    super.init()
  }

  func getToken() async throws -> AppCheckToken {
    let getTokenTask = Task { () -> AppCheckToken in
      // ...

      // Create AppCheckToken object.
      let exp = Date(timeIntervalSince1970: expirationFromServer)
      let token = AppCheckToken(
        token: tokenFromServer,
        expirationDate: exp
      )

      if Date() > exp {
        throw NSError(domain: "ExampleError", code: 1, userInfo: nil)
      }

      return token
    }

    return try await getTokenTask.value
  }

}

@interface YourCustomAppCheckProvider : NSObject <FIRAppCheckProvider>

@property FIRApp *app;

- (id)initWithApp:(FIRApp *)app;

@end

@implementation YourCustomAppCheckProvider

- (id)initWithApp:app {
    self = [super init];
    if (self) {
        self.app = app;
    }
    return self;
}

- (void)getTokenWithCompletion:(nonnull void (^)(FIRAppCheckToken * _Nullable,
                                                 NSError * _Nullable))handler {
    dispatch_async(dispatch_get_main_queue(), ^{
        // Logic to exchange proof of authenticity for an App Check token.
        // ...

        // Create FIRAppCheckToken object.
        NSTimeInterval exp = expirationFromServer;
        FIRAppCheckToken *token
            = [[FIRAppCheckToken alloc] initWithToken:tokenFromServer
                                       expirationDate:[NSDate dateWithTimeIntervalSince1970:exp]];

        // Pass the token or error to the completion handler.
        handler(token, nil);
    });
}

@end

class YourCustomAppCheckProviderFactory: NSObject, AppCheckProviderFactory {
  func createProvider(with app: FirebaseApp) -> AppCheckProvider? {
    return YourCustomAppCheckProvider(withFirebaseApp: app)
  }
}

@interface YourCustomAppCheckProviderFactory : NSObject <FIRAppCheckProviderFactory>
@end

@implementation YourCustomAppCheckProviderFactory

- (nullable id<FIRAppCheckProvider>)createProviderWithApp:(FIRApp *)app {
    return [[YourCustomAppCheckProvider alloc] initWithApp:app];
}

@end

let providerFactory = YourAppCheckProviderFactory()
AppCheck.setAppCheckProviderFactory(providerFactory)

FirebaseApp.configure()

YourAppCheckProviderFactory *providerFactory =
        [[YourAppCheckProviderFactory alloc] init];
[FIRAppCheck setAppCheckProviderFactory:providerFactory];

[FIRApp configure];