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docs/Writerside/topics/Authentication.md

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+# Authentication
+
+The HopFrame is a powerful tool to manage your backend data. So you probably don't want anybody to access the pages.
+Luckily the HopFrame supports policy based authentication. By default, everybody is allowed to access the whole
+HopFrame, but you can restrict that by registering a scoped service implementing the `IHopFrameAuthHandler`.
+If no service is registered, the default handler gets registered, but it lets any traffic pass.
+
+## Example
+
+Create a service that handles authentication:
+
+```C#
+public class AuthService(IAuthStore store) : IHopFrameAuthHandler {
+
+    public async Task<bool> IsAuthenticatedAsync(string? policy) {
+        var currentUser = await store.GetCurrentUser();
+        return await store.IsPermitted(currentUser, policy);
+    }
+    
+    public async Task<string> GetCurrentUserDisplayNameAsync() {
+        var currentUser = await store.GetCurrentUser();
+        return currentUser.FullName;
+    }
+    
+}
+```
+
+Now register it in the DI container:
+
+```C#
+builder.Services.AddScoped<IHopFrameAuthHandler, AuthService>();
+```
+
+**Hint:** You can display the current users name in the ui by enabling the feature in
+the [HopFrameConfig](HopFrameConfig.md#displayuserinfo).