您可以将 Facebook 登录机制集成到您的应用中,让您的用户能够使用自己的 Facebook 帐号进行 Firebase 身份验证。
准备工作
- 将 Firebase 添加到您的 iOS 项目。在您的
Podfile
中添加以下 Pod:pod 'Firebase/Auth'
- 如果您尚未将您的应用与 Firebase 项目相关联,请在 Firebase 控制台中进行关联。
- 在 Facebook for Developers 网站上,为您的应用获取应用 ID 和应用密钥。
- 启用 Facebook 登录机制:
- 在 Firebase 控制台中,打开身份验证部分。
- 在登录方法标签页上,启用 Facebook 登录方法,并指定您之前从 Facebook 获得的应用 ID 和应用密钥。
- 然后,请务必转到 Facebook for Developers 网站,依次点击 Product Settings > Facebook Login 配置,然后在您的 Facebook 应用的设置页面中,确保您的 OAuth 重定向 URI(例如
my-app-12345.firebaseapp.com/__/auth/handler
)出现在 OAuth redirect URIs 列表中。
进行 Firebase 身份验证
- 按开发者文档中的说明操作,将 Facebook 登录集成到您的应用中。当初始化
FBSDKLoginButton
对象时,设置一个委托来接收登录和退出帐号事件。例如:Swift
let loginButton = FBSDKLoginButton() loginButton.delegate = self
Objective-C
FBSDKLoginButton *loginButton = [[FBSDKLoginButton alloc] init]; loginButton.delegate = self;
didCompleteWithResult:error:
。Swift
func loginButton(_ loginButton: FBSDKLoginButton!, didCompleteWith result: FBSDKLoginManagerLoginResult!, error: Error!) { if let error = error { print(error.localizedDescription) return } // ... }
Objective-C
- (void)loginButton:(FBSDKLoginButton *)loginButton didCompleteWithResult:(FBSDKLoginManagerLoginResult *)result error:(NSError *)error { if (error == nil) { // ... } else { NSLog(error.localizedDescription); } }
- 在
UIApplicationDelegate
中导入 Firebase 模块:Swift
import Firebase
Objective-C
@import Firebase;
- 配置一个
FirebaseApp
共享实例(通常在应用的application:didFinishLaunchingWithOptions:
方法中配置):Swift
// Use Firebase library to configure APIs FirebaseApp.configure()
Objective-C
// Use Firebase library to configure APIs [FIRApp configure];
- 用户成功登录后,您可在
didCompleteWithResult:error:
的实现代码中,为已登录的用户获取一个访问令牌,然后用该访问令牌换取 Firebase 凭据:Swift
let credential = FacebookAuthProvider.credential(withAccessToken: AccessToken.current!.tokenString)
Objective-C
FIRAuthCredential *credential = [FIRFacebookAuthProvider credentialWithAccessToken:[FBSDKAccessToken currentAccessToken].tokenString];
- 最后,使用 Firebase 凭据进行 Firebase 身份验证:
Swift
Auth.auth().signIn(with: credential) { (authResult, error) in if let error = error { let authError = error as NSError if (isMFAEnabled && authError.code == AuthErrorCode.secondFactorRequired.rawValue) { // The user is a multi-factor user. Second factor challenge is required. let resolver = authError.userInfo[AuthErrorUserInfoMultiFactorResolverKey] as! MultiFactorResolver var displayNameString = "" for tmpFactorInfo in (resolver.hints) { displayNameString += tmpFactorInfo.displayName ?? "" displayNameString += " " } self.showTextInputPrompt(withMessage: "Select factor to sign in\n\(displayNameString)", completionBlock: { userPressedOK, displayName in var selectedHint: PhoneMultiFactorInfo? for tmpFactorInfo in resolver.hints { if (displayName == tmpFactorInfo.displayName) { selectedHint = tmpFactorInfo as? PhoneMultiFactorInfo } } PhoneAuthProvider.provider().verifyPhoneNumber(with: selectedHint!, uiDelegate: nil, multiFactorSession: resolver.session) { verificationID, error in if error != nil { print("Multi factor start sign in failed. Error: \(error.debugDescription)") } else { self.showTextInputPrompt(withMessage: "Verification code for \(selectedHint?.displayName ?? "")", completionBlock: { userPressedOK, verificationCode in let credential: PhoneAuthCredential? = PhoneAuthProvider.provider().credential(withVerificationID: verificationID!, verificationCode: verificationCode!) let assertion: MultiFactorAssertion? = PhoneMultiFactorGenerator.assertion(with: credential!) resolver.resolveSignIn(with: assertion!) { authResult, error in if error != nil { print("Multi factor finanlize sign in failed. Error: \(error.debugDescription)") } else { self.navigationController?.popViewController(animated: true) } } }) } } }) } else { self.showMessagePrompt(error.localizedDescription) return } // ... return } // User is signed in // ... }
Objective-C
[[FIRAuth auth] signInWithCredential:credential completion:^(FIRAuthDataResult * _Nullable authResult, NSError * _Nullable error) { if (isMFAEnabled && error && error.code == FIRAuthErrorCodeSecondFactorRequired) { FIRMultiFactorResolver *resolver = error.userInfo[FIRAuthErrorUserInfoMultiFactorResolverKey]; NSMutableString *displayNameString = [NSMutableString string]; for (FIRMultiFactorInfo *tmpFactorInfo in resolver.hints) { [displayNameString appendString:tmpFactorInfo.displayName]; [displayNameString appendString:@" "]; } [self showTextInputPromptWithMessage:[NSString stringWithFormat:@"Select factor to sign in\n%@", displayNameString] completionBlock:^(BOOL userPressedOK, NSString *_Nullable displayName) { FIRPhoneMultiFactorInfo* selectedHint; for (FIRMultiFactorInfo *tmpFactorInfo in resolver.hints) { if ([displayName isEqualToString:tmpFactorInfo.displayName]) { selectedHint = (FIRPhoneMultiFactorInfo *)tmpFactorInfo; } } [FIRPhoneAuthProvider.provider verifyPhoneNumberWithMultiFactorInfo:selectedHint UIDelegate:nil multiFactorSession:resolver.session completion:^(NSString * _Nullable verificationID, NSError * _Nullable error) { if (error) { [self showMessagePrompt:error.localizedDescription]; } else { [self showTextInputPromptWithMessage:[NSString stringWithFormat:@"Verification code for %@", selectedHint.displayName] completionBlock:^(BOOL userPressedOK, NSString *_Nullable verificationCode) { FIRPhoneAuthCredential *credential = [[FIRPhoneAuthProvider provider] credentialWithVerificationID:verificationID verificationCode:verificationCode]; FIRMultiFactorAssertion *assertion = [FIRPhoneMultiFactorGenerator assertionWithCredential:credential]; [resolver resolveSignInWithAssertion:assertion completion:^(FIRAuthDataResult * _Nullable authResult, NSError * _Nullable error) { if (error) { [self showMessagePrompt:error.localizedDescription]; } else { NSLog(@"Multi factor finanlize sign in succeeded."); } }]; }]; } }]; }]; } else if (error) { // ... return; } // User successfully signed in. Get user data from the FIRUser object if (authResult == nil) { return; } FIRUser *user = authResult.user; // ... }];
后续步骤
在用户首次登录后,系统会创建一个新的用户帐号,并将其与该用户登录时使用的凭据(即用户名和密码、电话号码或者身份验证提供方信息)相关联。此新帐号存储在您的 Firebase 项目中,无论用户采用何种方式登录,您项目中的每个应用都可以使用此帐号来识别用户。
在您的 Firebase Realtime Database 和 Cloud Storage 安全规则中,您可以从
auth
变量获取已登录用户的唯一用户 ID,然后利用此 ID 来控制用户可以访问哪些数据。
您可以通过将身份验证提供方凭据关联至现有用户帐号,让用户可以使用多个身份验证提供方登录您的应用。
如需让用户退出登录,请调用 signOut:
。
Swift
let firebaseAuth = Auth.auth() do { try firebaseAuth.signOut() } catch let signOutError as NSError { print ("Error signing out: %@", signOutError) }
Objective-C
NSError *signOutError; BOOL status = [[FIRAuth auth] signOut:&signOutError]; if (!status) { NSLog(@"Error signing out: %@", signOutError); return; }
您可能还需要为所有身份验证错误添加错误处理代码。请参阅处理错误。