為使用者設定自訂的憑證附加資訊

本文將說明如何使用 Identity Platform 針對使用者設定自訂憑證附加資訊。自訂憑證附加資訊會在驗證期間插入使用者權杖。應用程式可以使用這些宣告來處理複雜的授權情境，例如根據使用者的角色限制其對資源的存取權。

設定自訂憑證

為確保安全性，請在伺服器上使用 Admin SDK 設定自訂宣稱：

  1. 如果您尚未安裝，請安裝 Admin SDK。

  2. 設定要使用的自訂宣告。在以下範例中，系統會為使用者設定自訂宣稱，說明使用者是管理員：

    Node.js

    // Set admin privilege on the user corresponding to uid.

getAuth()
  .setCustomUserClaims(uid, { admin: true })
  .then(() => {
    // The new custom claims will propagate to the user's ID token the
    // next time a new one is issued.
  });
    custom_claims.js

    Java

    // Set admin privilege on the user corresponding to uid.
Map<String, Object> claims = new HashMap<>();
claims.put("admin", true);
FirebaseAuth.getInstance().setCustomUserClaims(uid, claims);
// The new custom claims will propagate to the user's ID token the
// next time a new one is issued.
    FirebaseAuthSnippets.java

    Python

    # Set admin privilege on the user corresponding to uid.
auth.set_custom_user_claims(uid, {'admin': True})
# The new custom claims will propagate to the user's ID token the
# next time a new one is issued.
    index.py

    Go

    // Get an auth client from the firebase.App
client, err := app.Auth(ctx)
if err != nil {
	log.Fatalf("error getting Auth client: %v\n", err)
}

// Set admin privilege on the user corresponding to uid.
claims := map[string]interface{}{"admin": true}
err = client.SetCustomUserClaims(ctx, uid, claims)
if err != nil {
	log.Fatalf("error setting custom claims %v\n", err)
}
// The new custom claims will propagate to the user's ID token the
// next time a new one is issued.
    auth.go

    C#

    // Set admin privileges on the user corresponding to uid.
var claims = new Dictionary<string, object>()
{
    { "admin", true },
};
await FirebaseAuth.DefaultInstance.SetCustomUserClaimsAsync(uid, claims);
// The new custom claims will propagate to the user's ID token the
// next time a new one is issued.
    FirebaseAuthSnippets.cs

  3. 在下次將自訂權利要求傳送至伺服器時，驗證權利要求：

    Node.js

    // Verify the ID token first.
getAuth()
  .verifyIdToken(idToken)
  .then((claims) => {
    if (claims.admin === true) {
      // Allow access to requested admin resource.
    }
  });
    custom_claims.js

    Java

    // Verify the ID token first.
FirebaseToken decoded = FirebaseAuth.getInstance().verifyIdToken(idToken);
if (Boolean.TRUE.equals(decoded.getClaims().get("admin"))) {
  // Allow access to requested admin resource.
}
    FirebaseAuthSnippets.java

    Python

    # Verify the ID token first.
claims = auth.verify_id_token(id_token)
if claims['admin'] is True:
    # Allow access to requested admin resource.
    pass
    index.py

    Go

    // Verify the ID token first.
token, err := client.VerifyIDToken(ctx, idToken)
if err != nil {
	log.Fatal(err)
}

claims := token.Claims
if admin, ok := claims["admin"]; ok {
	if admin.(bool) {
		//Allow access to requested admin resource.
	}
}
    auth.go

    C#

    // Verify the ID token first.
FirebaseToken decoded = await FirebaseAuth.DefaultInstance.VerifyIdTokenAsync(idToken);
object isAdmin;
if (decoded.Claims.TryGetValue("admin", out isAdmin))
{
    if ((bool)isAdmin)
    {
        // Allow access to requested admin resource.
    }
}

    FirebaseAuthSnippets.cs

  4. 如要判斷使用者有哪些自訂憑證附加資訊，請按照下列步驟操作：

    Node.js

    // Lookup the user associated with the specified uid.
getAuth()
  .getUser(uid)
  .then((userRecord) => {
    // The claims can be accessed on the user record.
    console.log(userRecord.customClaims['admin']);
  });
    custom_claims.js

    Java

    // Lookup the user associated with the specified uid.
UserRecord user = FirebaseAuth.getInstance().getUser(uid);
System.out.println(user.getCustomClaims().get("admin"));
    FirebaseAuthSnippets.java

    Python

    # Lookup the user associated with the specified uid.
user = auth.get_user(uid)
# The claims can be accessed on the user record.
print(user.custom_claims.get('admin'))
    index.py

    Go

    // Lookup the user associated with the specified uid.
user, err := client.GetUser(ctx, uid)
if err != nil {
	log.Fatal(err)
}
// The claims can be accessed on the user record.
if admin, ok := user.CustomClaims["admin"]; ok {
	if admin.(bool) {
		log.Println(admin)
	}
}
    auth.go

    C#

    // Lookup the user associated with the specified uid.
UserRecord user = await FirebaseAuth.DefaultInstance.GetUserAsync(uid);
Console.WriteLine(user.CustomClaims["admin"]);
    FirebaseAuthSnippets.cs

設定自訂宣告時，請注意下列事項：

  • 自訂聲明的大小不得超過 1000 個位元組。如果嘗試傳遞的聲明大於 1000 個位元組，系統會傳回錯誤。
  • 權杖核發時，系統會將自訂權杖附加資訊插入使用者 JWT。權杖重新整理後，才能使用新的宣告。您可以呼叫 user.getIdToken(true) 來靜默重新整理權杖。
  • 為維持連續性和安全性，請只在安全的伺服器環境中設定自訂宣告。

後續步驟