verisoul_sdk 0.4.74

Verisoul helps businesses stop fake accounts and fraud

Flutter SDK

Verisoul provides a Flutter SDK that allows you to implement fraud prevention in your cross-platform mobile applications. This guide covers the installation, configuration, and usage of the Verisoul Flutter SDK.

To run the SDK a Verisoul Project ID is required. Schedule a call here to get started.

System Requirements

• Flutter SDK 3.0 or higher
• Dart 2.17 or higher
• iOS 14.0 or higher
• Android API level 24 (Android 7.0) or higher
• For Web: Modern browsers with JavaScript enabled
• SDK Size: ~120 KB (plus native iOS and Android SDK dependencies)

Installation

Add Dependency

dependencies:
  flutter:
    sdk: flutter
  #  ...

  verisoul_sdk: 0.4.74

Android Configuration

1. Update Minimum SDK Version

Update the Android minimum minSdk to 24 in android/app/build.gradle:

 defaultConfig {
    minSdk = 24
    //...
}

2. Add Maven Repository

If an exception occurs during the build stating that the ai.verisoul:android package cannot be downloaded, add the following Maven repository inside your android/build.gradle file:

allprojects {
    repositories {
    // ...

     maven { url = uri("https://us-central1-maven.pkg.dev/verisoul/android") }

    }
 }

iOS Configuration

For iOS-specific configuration including Device Check and App Attest setup, please refer to the iOS SDK Documentation.

Usage

Initialize the SDK

Call configure() before you intend to retrieve a Verisoul session_id:

import 'package:verisoul_sdk/verisoul.dart';

void main() {
   WidgetsFlutterBinding.ensureInitialized();
   VerisoulSdk.configure(projectId: "Project ID ", environment: VerisoulEnvironment.prod);
   runApp(const MyApp());
}

The configure() method initializes the Verisoul SDK with your project credentials. Only initialize the SDK if you plan to retrieve a session_id and call the Verisoul API for that session.

Parameters:

• projectId: Your unique Verisoul project identifier
• environment: The environment to use VerisoulEnvironment.prod for production or VerisoulEnvironment.sandbox for testing

Get Session ID

The getSessionApi() method returns the current session identifier after the SDK has collected sufficient device data. This session ID is required to request a risk assessment from Verisoul's API.

Important Notes:

• Session IDs are short-lived and expire after 24 hours
• The session ID becomes available once minimum data collection is complete (typically within seconds)
• You should send this session ID to your backend, which can then call Verisoul's API to get a risk assessment

Example:

final session = await VerisoulSdk.getSessionApi();

On iOS, the SDK collects data only while the app is in the foreground. If getSessionApi() is called while the app is in the background (for example during a silent push, background fetch, or location update), it returns once the user opens the app. A cached session is returned right away, and the timeout counts only time spent in the foreground. Don't await getSessionApi() inside background handlers or in other code that has to finish while the app is in the background.

Provide Touch Events

Wrap your App with VerisoulWrapper to automatically capture touch events:

runApp(VerisoulWrapper(child: const MyApp()));

Error Codes

The SDK throws VerisoulException with the following error codes:

Error Code	Description	Recommended Action
INVALID_ENVIRONMENT	The environment parameter passed to Verisoul.configure() is invalid. Valid values are "dev", "sandbox", or "prod".	Ensure Verisoul.configure() parameter is exactly: • "dev", "sandbox", or "prod" • Case-sensitive • Free of whitespace
SESSION_UNAVAILABLE	A valid session ID could not be obtained. This typically occurs when Verisoul's servers are unreachable due to network blocking or a very slow connection.	• Implement exponential backoff. • Prompt user to check network or disable network blocker. • Log to identify blocking issues.
WEBVIEW_UNAVAILABLE	WebView is not available on the device. This can occur when WebView is disabled, missing, uninstalled, or corrupted on the device.	Prompt user to: • Enable WebView in settings • Update Android System WebView • Switch devices
WEBVIEW_RENDERER_CRASHED	The WebView renderer process crashed, typically due to low memory or resource pressure.	• Retry the request (SDK will attempt recovery). • Encourage users to update Android System WebView. • Switch devices

Exception Structure

All errors are thrown as VerisoulException with the following properties:

Property	Type	Description
code	String	One of the error codes above
message	String	Human-readable error description
cause	Throwable?	The underlying exception that caused the error (if any)

Web Support

Add Verisoul Script

Add the Verisoul script to your web/index.html:

<script
  async
  src="https://js.verisoul.ai/{env}/bundle.js"
  verisoul-project-id="{project_id}"
></script>

Replace the following parameters:

• {env}: Use either prod or sandbox
• {project_id}: Your project ID, which must match the environment

Content Security Policy (CSP)

If your application has a Content Security Policy, update it to include the following Verisoul domains:

<meta
  http-equiv="Content-Security-Policy"
  content="script-src 'self' https://js.verisoul.ai; worker-src 'self' blob: data:;connect-src 'self' https://*.verisoul.ai wss://*.verisoul.ai;"
/>

Set Account Data (Web Only)

The setAccountData() function provides a simplified way to send user account information to Verisoul directly from the client side. While easy to integrate, this method has important limitations:

• Offline analysis only: Data sent via account() is only visible in the Verisoul dashboard
• No real-time decisions: Unlike the server-side API, this method doesn't allow your application to receive and act on Verisoul's risk scores in real-time
• Limited use case: Designed specifically for initial pilots and evaluation purposes

await VerisoulSdk.setAccountData(
  id: "example-id",
  email: "[e-mail]",
  metadata: {"paid": true}
);

Example

For a complete working example, see the example folder in this repository.

Additional Resources

• Verisoul Flutter SDK