Zero-tap authentication templates | Developer Documentation

./sms_retriever_hash_v9.sh --package "com.example.myapplication" --keystore ~/.android/debug.keystore

dependencies {
    …
    implementation 'com.whatsapp.otp:whatsapp-otp-android-sdk:1.0.0'
    …
}

repositories {
    …
    mavenCentral()
    …
}

<receiver
   android:name=".app.receiver.OtpCodeReceiver"
   android:enabled="true"
   android:exported="true">
   <intent-filter>
       <action android:name="com.whatsapp.otp.OTP_RETRIEVED" />
   </intent-filter>
</receiver>

public class OtpCodeReceiver extends BroadcastReceiver {

  @Override
  public void onReceive(Context context, Intent intent) {
    WhatsAppOtpIncomingIntentHandler whatsAppOtpIncomingIntentHandler = new WhatsAppOtpIncomingIntentHandler();

    // Retrieve the expected handshake ID that was stored during handshake initiation
    String expectedHandshakeId = retrieveStoredHandshakeId();

    whatsAppOtpIncomingIntentHandler.processOtpCode(intent,
      expectedHandshakeId,
      (code) -> {
        // The handshake ID has been validated by the SDK
        validateCode(code);
      },
      // call your function to handle errors
      (error, exception) -> handleError(error, exception));
  }
}

public class OtpCodeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        String incomingRequestId = intent.getStringExtra("request_id");

        // Retrieve the previously stored handshake ID
        String storedRequestId = retrieveStoredRequestId();

        // Validate the handshake ID matches
        if (storedRequestId != null && storedRequestId.equals(incomingRequestId)) {
            // use OTP code
            String otpCode = intent.getStringExtra("code");
            // ...
        }
    }
}

<activity
   android:name=".ReceiveCodeActivity"
   android:enabled="true"
   android:exported="true"
   android:launchMode="standard">
   <intent-filter>
       <action android:name="com.whatsapp.otp.OTP_RETRIEVED" />
   </intent-filter>
</activity>

public class ReceiveCodeActivity extends AppCompatActivity {

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       Intent intent = getIntent();

       // Extract the handshake ID from the intent
       String incomingRequestId = intent.getStringExtra("request_id");

       // Retrieve the previously stored handshake ID
       String storedRequestId = retrieveStoredRequestId();

       // Validate the handshake ID matches
       if (storedRequestId != null && storedRequestId.equals(incomingRequestId)) {
         // use OTP code
         String otpCode = intent.getStringExtra("code");
         // ...
       }
   }
}

WhatsAppOtpHandler whatsAppOtpHandler = new WhatsAppOtpHandler();
UUID handshakeId = whatsAppOtpHandler.sendOtpIntentToWhatsApp(context);
// Store handshakeId to validate the received OTP code later

private String currentRequestId;

public void sendOtpIntentToWhatsApp() {
   // Generate a unique handshake ID
   currentRequestId = UUID.randomUUID().toString();
   // Store this ID for later validation when receiving the OTP
   storeRequestId(currentRequestId);

   // Send OTP_REQUESTED intent to both WA and WA Business App
   sendOtpIntentToWhatsApp("com.whatsapp", currentRequestId);
   sendOtpIntentToWhatsApp("com.whatsapp.w4b", currentRequestId);
}

private void sendOtpIntentToWhatsApp(String packageName, String requestId) {

  /**
  * Starting with Build.VERSION_CODES.S, it will be required to explicitly
  * specify the mutability of  PendingIntents on creation with either
  * (@link #FLAG_IMMUTABLE} or FLAG_MUTABLE
  */
  int flags = Build.VERSION.SDK_INT >= Build.VERSION_CODES.S ? FLAG_IMMUTABLE : 0;
  PendingIntent pi = PendingIntent.getActivity(
      getApplicationContext(),
      0,
      new Intent(),
      flags);

  // Send OTP_REQUESTED intent to WhatsApp
  Intent intentToWhatsApp = new Intent();
  intentToWhatsApp.setPackage(packageName);
  intentToWhatsApp.setAction("com.whatsapp.otp.OTP_REQUESTED");
  // WA will use this to verify the identity of the caller app.
  Bundle extras = intentToWhatsApp.getExtras();
  if (extras == null) {
     extras = new Bundle();
  }
  extras.putParcelable("_ci_", pi);
  // Add the handshake ID for secure validation
  intentToWhatsApp.putExtra("request_id", requestId);
  intentToWhatsApp.putExtras(extras);
  getApplicationContext().sendBroadcast(intentToWhatsApp);
}

WhatsAppOtpHandler whatsAppOtpHandler = new WhatsAppOtpHandler();

If (whatsAppOtpHandler.isWhatsAppInstalled(context)) {
    // ... do something
}