首先使用Facebook进行身份验证然后使用Google导致Firebase for Android出现错误

Question

据我在Firebase文档中了解,如果用户使用凭据对其帐户进行身份验证,则如果凭据尚未与其他凭据相关联,则应使用相同的凭据严格登录.

换句话说,如果我使用Google登录创建帐户,然后(退出后)尝试使用与Google凭据相同的电子邮件登录Facebook凭据,我应该在logcat中看到此异常:

"已存在具有相同电子邮件地址但登录凭据不同的帐户.请使用与此电子邮件地址关联的提供商登录."

是的,我毫不奇怪地得到了这个例外.但是,如果我使用Facebook创建帐户,然后尝试使用Google凭据登录,则此帐户(Facebook)的提供商将转换为Google.此时身份验证不会失败,但不是预期的结果.我想以某种方式将每个用户与特定凭据相关联.我该怎么解决这个问题？你可以看到下面的代码:

public class SignInActivity extends AppCompatActivity implements GoogleApiClient.OnConnectionFailedListener,
        View.OnClickListener {

    private static final String TAG = "SignInActivity";
    private static final int RC_SIGN_IN = 9001;

    private GoogleApiClient mGoogleApiClient;
    private FirebaseAuth mFirebaseAuth;
    private FirebaseAuth.AuthStateListener mFirebaseAuthListener;

    private CallbackManager mCallbackManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_sign_in);

        // Facebook Login
        FacebookSdk.sdkInitialize(getApplicationContext());
        mCallbackManager = CallbackManager.Factory.create();

        LoginButton mFacebookSignInButton = (LoginButton) findViewById(R.id.facebook_login_button);
        mFacebookSignInButton.setReadPermissions("email", "public_profile");

        mFacebookSignInButton.registerCallback(mCallbackManager, new FacebookCallback<LoginResult>() {
            @Override
            public void onSuccess(LoginResult loginResult) {
                Log.d(TAG, "facebook:onSuccess:" + loginResult);
                firebaseAuthWithFacebook(loginResult.getAccessToken());
            }

            @Override
            public void onCancel() {
                Log.d(TAG, "facebook:onCancel");
            }

            @Override
            public void onError(FacebookException error) {
                Log.d(TAG, "facebook:onError", error);
            }
        });

        // Google Sign-In
        // Assign fields
        SignInButton mGoogleSignInButton = (SignInButton) findViewById(R.id.google_sign_in_button);

        // Set click listeners
        mGoogleSignInButton.setOnClickListener(this);

        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken(getString(R.string.default_web_client_id))
                .requestEmail()
                .build();
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */)
                .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
                .build();

        // Initialize FirebaseAuth
        mFirebaseAuth = FirebaseAuth.getInstance();

        mFirebaseAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                FirebaseUser user = firebaseAuth.getCurrentUser();
                if (user != null) {
                    // User is signed in
                    Log.d(TAG, "onAuthStateChanged:signed_in:" + user.getUid());
                } else {
                    // User is signed out
                    Log.d(TAG, "onAuthStateChanged:signed_out");
                }
            }
        };
    }

    @Override
    public void onStart() {
        super.onStart();
        mFirebaseAuth.addAuthStateListener(mFirebaseAuthListener);
    }

    @Override
    public void onStop() {
        super.onStop();
        if (mFirebaseAuthListener != null) {
            mFirebaseAuth.removeAuthStateListener(mFirebaseAuthListener);
        }
    }

    private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
        Log.d(TAG, "firebaseAuthWithGooogle:" + acct.getId());
        AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
        mFirebaseAuth.signInWithCredential(credential)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        Log.d(TAG, "signInWithCredential:onComplete:" + task.isSuccessful());

                        // If sign in fails, display a message to the user. If sign in succeeds
                        // the auth state listener will be notified and logic to handle the
                        // signed in user can be handled in the listener.
                        if (!task.isSuccessful()) {
                            Log.w(TAG, "signInWithCredential", task.getException());
                            Toast.makeText(SignInActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        } else {
                            startActivity(new Intent(SignInActivity.this, MainActivity.class));
                            finish();
                        }
                    }
                });
    }

    private void firebaseAuthWithFacebook(AccessToken token) {
        Log.d(TAG, "handleFacebookAccessToken:" + token);

        final AuthCredential credential = FacebookAuthProvider.getCredential(token.getToken());
        mFirebaseAuth.signInWithCredential(credential)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        Log.d(TAG, "signInWithCredential:onComplete:" + task.isSuccessful());

                        // If sign in fails, display a message to the user. If sign in succeeds
                        // the auth state listener will be notified and logic to handle the
                        // signed in user can be handled in the listener.
                        if (!task.isSuccessful()) {
                            Log.w(TAG, "signInWithCredential", task.getException());
                            Toast.makeText(SignInActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        }

                        else {
                            startActivity(new Intent(SignInActivity.this, MainActivity.class));
                            finish();
                        }
                    }
                });
    }

    /*
    private void handleFirebaseAuthResult(AuthResult authResult) {
        if (authResult != null) {
            // Welcome the user
            FirebaseUser user = authResult.getUser();
            Toast.makeText(this, "Welcome " + user.getEmail(), Toast.LENGTH_SHORT).show();

            // Go back to the main activity
            startActivity(new Intent(this, MainActivity.class));
        }
    }
    */

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.google_sign_in_button:
                signIn();
                break;
            default:
                return;
        }
    }

    private void signIn() {
        Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        mCallbackManager.onActivityResult(requestCode, resultCode, data);

        // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
            if (result.isSuccess()) {
                // Google Sign In was successful, authenticate with Firebase
                GoogleSignInAccount account = result.getSignInAccount();
                firebaseAuthWithGoogle(account);
            } else {
                // Google Sign In failed
                Log.e(TAG, "Google Sign In failed.");
            }
        }
    }

    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
        // An unresolvable error has occurred and Google APIs (including Sign-In) will not
        // be available.
        Log.d(TAG, "onConnectionFailed:" + connectionResult);
        Toast.makeText(this, "Google Play Services error.", Toast.LENGTH_SHORT).show();
    }
}

Answer 1

您正在寻找允许使用相同的电子邮件地址创建多个帐户。

Answer 2

请查看主题:https://groups.google.com/forum/#!searchin /firebase- talk/ liu /firebase- talk /ms_NVQem_Cw/8g7BFk1IAAAJ它解释了为什么会发生这种情况.这是由于某些安全问题导致Google电子邮件被验证,而Facebook电子邮件却没有.

Answer 3

我终于以这个逻辑结束了:

如果用户尝试使用Facebook登录,但已存在给定电子邮件的用户(使用Google提供商),则会发生此错误:

"已存在具有相同电子邮件地址但登录凭据不同的帐户.请使用与此电子邮件地址关联的提供商登录."

因此,只需要求用户使用Google进行登录(之后将其静默链接到现有帐户)

Answer 4

为了最大限度地减少登录UI点击而不影响帐户安全性,Firebase身份验证具有"可信提供商"的概念,其中身份提供商也是电子邮件服务提供商.例如,Google是@ gmail.com地址的可信赖提供商,Yahoo是@ yahoo.com地址的可靠提供商,Microsoft是@look.com地址的可信提供商.

在"每个电子邮件地址一个帐户"模式下,Firebase身份验证会尝试根据电子邮件地址关联帐户.如果用户从可信提供商登录,则用户立即登录该帐户,因为我们知道该用户拥有该电子邮件地址.

如果现有帐户具有相同的电子邮件地址但使用不受信任的凭据(例如,不可信的提供商或密码)创建,则出于安全原因,将删除先前的凭据.网络钓鱼者(不是电子邮件地址所有者)可能会创建初始帐户 - 删除初始凭据会阻止网络钓鱼者随后访问该帐户.

金柳

Answer 5

在 firebase 中，通过发送验证电子邮件来验证用户首次登录 Facebook 时的电子邮件帐户非常重要。

验证电子邮件后，如果用户使用@gmail.com 作为电子邮件地址，您可以同时使用 Facebook 和 Gmail 登录。

Facebook 登录 -> 单击验证电子邮件中的链接 -> Gmail 登录 -> Facebook 登录（确定）

Facebook 登录 -> Gmail 登录 -> 单击验证电子邮件中的链接 -> Facebook 登录（不正常）

如果您在用户注销前未验证 Facebook 电子邮件并尝试使用他们的 gmail 登录，则当他们使用他们的 gmail 登录时，您将无法再次使用 Facebook 登录。

更新 - 如果您选择始终信任 Facebook 电子邮件。

您可以设置一个 firebase 函数（触发器），当第一次通过 Facebook 帐户登录时，它会自动将 emailVerified 设置为 true。

示例代码。

const functions = require('firebase-functions');
const admin = require('firebase-admin');

exports.app = functions.auth.user().onCreate( async (user) => {

  if (user.providerData.find(d => d && d.providerId === 'facebook.com') || user.providerData === 'facebook.com') {
    
      try {
      await admin.auth().updateUser(user.uid, {
          emailVerified: true
        })
      } catch (err) {
        console.log('err when verifying email', err)
      }
  }
})

文档：Firebase 身份验证触发器