# Authentication - Android

### Authenticate User (Optional)

You can authenticate the user that is currently logged in before calling **`navigateToOneTalk`**. To do this, you can add an authentication method in the previously created Java Module. (See [Get Started - Android](https://docs.taptalk.io/onetalk-omnichannel-documentation/onetalk-channel-integration/live-chat/get-started-android#configure-and-initialize-taptalk.io-omnichannel-android-sdk-for-react-native-project)). We will add a `@ReactMethod` named **`authenticateUser`**.

{% code title="OneTalkStarterModule.java" %}

```java
import android.content.Intent;

import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;

import org.jetbrains.annotations.NotNull;

class OneTalkStarterModule extends ReactContextBaseJavaModule {

    OneTalkStarterModule(ReactApplicationContext reactContext) {
        super(reactContext);
    }

    @NotNull
    @Override
    public String getName() {
        return "OneTalkStarter";
    }

    @ReactMethod
    void navigateToOneTalk() {
        Intent intent = new Intent(getReactApplicationContext(), OneTalkWrapperActivity.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        getReactApplicationContext().startActivity(intent);
    }
    
    @ReactMethod
    void authenticateUser(String name, String email, Callback successCallback, Callback errorCallback) {
        TapTalkLive.authenticateUser(name, email, new TTLCommonListener() {
            @Override
            public void onSuccess(String successMessage) {
                successCallback.invoke(successMessage);
            }
            @Override
            public void onError(String errorCode, String errorMessage) {
                errorCallback.invoke(errorMessage);
            }
        });
    }
}
```

{% endcode %}

{% hint style="info" %}
**Parameters**

**`name`**: (String) name of the user to be authenticated

**`email`**: (String) email of the user to be authenticated

**`successCallback`**: (Callback) invoked when the authentication is successful

**`errorCallback`**: (Callback) invoked when an error occurred during authentication
{% endhint %}

You can then call the method from JavaScript as such:

```javascript
NativeModules.OneTalkStarter.authenticateUser(
    'USER_NAME', 
    'USER_EMAIL',
    (successMessage) => {
        // Successfully authenticated user
    },
    (errorMessage) => {
        // An error occurred during authentication
      }
);
```

After successfully authenticated, user will no longer be required to fill name and email to create a case.

### Logout and Clear TapTalkLive Data

You may also add another method when you need to logout and clear all local cached data from Omnichannel SDK. We will name this method **`clearAllTapLiveData`**.

{% code title="OneTalkStarterModule.java" %}

```java
import io.taptalk.taptalklive.TapTalkLive;

class OneTalkStarterModule extends ReactContextBaseJavaModule {

    ...
    
    @ReactMethod
    void clearAllTapLiveData() {
        TapTalkLive.clearAllTapLiveData();
    }
}
```

{% endcode %}

You can then call the method from JavaScript when needed.

```javascript
NativeModules.OneTalkStarter.clearAllTapLiveData();
```