Recommended for Flutter

Flutter Verification SDK

Official Flutter SDK for identity verification with WebView integration. Add document and liveness verification to your Flutter app with just a few lines of code.

Open Source on GitHub

View source code, examples, and detailed integration guides

View on GitHub

Key Features

Secure

API key stays on your backend server

Cross-platform

Works on Android and iOS

Customizable

Configure base URL, auto-close, and other settings

Easy Integration

Simple API with just a few lines of code

Full Verification

Document capture and liveness detection

Auto-close

Automatic WebView closing after verification

Installation

Add the Flutter Verification SDK to your project's pubspec.yaml file:

pubspec.yaml

dependencies:
  flutter_verification_sdk: ^0.1.0

Then run:

flutter pub get
flutter clean  # Recommended to ensure proper manifest merging

Platform Setup

Android

The SDK automatically includes required permissions and FileProvider configuration. Verify your android/app/build.gradle has:

minSdkVersion 21

Note: The SDK's AndroidManifest.xml automatically merges with your app's manifest, including camera, internet, and storage permissions, plus FileProvider for camera capture.

iOS

Add the following to your ios/Runner/Info.plist:

<key>NSCameraUsageDescription</key>
<string>Camera access is required for document and liveness verification</string>
<key>NSPhotoLibraryUsageDescription</key>
<string>Photo library access to upload document images</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>Location verification for identity confirmation</string>

Quick Start

Security Best Practice

Never include your API key in your mobile app. Always generate the verification ID on your secure backend server.

Step 1: Get a verification ID from your backend

// Call YOUR backend endpoint
final response = await http.post(
  Uri.parse('https://your-api.com/generate-verification'),
  headers: {'Authorization': 'Bearer $yourAuthToken'},
);

final data = jsonDecode(response.body);
final verificationId = data['verificationId'];

Step 2: Start the verification

import 'package:flutter_verification_sdk/flutter_verification_sdk.dart';

final result = await VerificationSDK.startVerification(
  context: context,
  verificationId: verificationId,
  config: VerificationConfig.production(),  // Auto-closes after 2 seconds
);

// Handle the result
if (result.isSuccessful) {
  print('Verification completed!');
  print('Status: ${result.verificationStatus}');
  // Update your UI, notify backend, navigate to next screen, etc.
} else if (result.wasCancelled) {
  print('User cancelled');
} else if (result.hasError) {
  print('Error: ${result.errorMessage}');
}

Configuration Options

Environment Configuration

// Production environment (auto-closes after 2 seconds)
VerificationConfig.production()

// Staging environment
VerificationConfig.staging()

// Custom configuration with auto-close
VerificationConfig(
  baseUrl: 'https://your-custom-url.com',
  debugMode: true,
  timeout: Duration(minutes: 30),
  autoClose: true,  // Automatically close after completion
  autoCloseDelay: Duration(seconds: 3),  // Wait 3 seconds before closing
)

// Disable auto-close (user must manually close)
VerificationConfig(
  baseUrl: 'https://verify.test.okid.io',
  autoClose: false,  // Stay on result screen, user closes manually
)

Auto-Close Behavior

By default, the SDK automatically closes the WebView 2 seconds after verification completes, allowing users to see the success/failure status briefly.

autoClose: true (default) - WebView closes automatically after autoCloseDelay
autoClose: false - WebView stays open on result screen, user closes manually
autoCloseDelay - Duration to show result before auto-closing (default: 2 seconds)

Viewport Scaling

The SDK uses 95% initial scale by default to ensure content fits without scrolling on mobile screens.

VerificationConfig(
  baseUrl: 'https://verify.test.okid.io',
  initialScale: 100,  // Use 100% if you prefer no scaling
)

Verification Result

The VerificationResult object contains:

status - The outcome (completed, cancelled, error, expired)
verificationId - The verification ID
verificationStatus - Backend status (e.g., "verified", "rejected")
errorMessage - Error details if status is error
timestamp - When the result was received

Convenience Properties

isSuccessful - True if verification completed
wasCancelled - True if user cancelled
hasError - True if an error occurred
isExpired - True if session timed out

Backend Integration

Your backend server must provide an endpoint that generates verification IDs. The SDK repository includes detailed backend implementation examples in various languages.

Quick Example (Node.js)

app.post('/api/mobile/generate-verification', async (req, res) => {
  const response = await fetch('https://verify.test.okid.io/api/generate-verification', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json',
      'X-SDK-Key': process.env.OKID_API_KEY,  // Your API key - server-side only!
    },
    body: JSON.stringify({
      extra_data: {
        user_id: req.user.id,
      }
    }),
  });
  
  const data = await response.json();
  res.json({ verificationId: data.verificationId });
});

Complete Backend Integration Guide

For detailed backend implementation examples in Node.js, Python, PHP, and more, see the INTEGRATION.md file in the GitHub repository.

Security Best Practices

✅ Do

Generate verification IDs on your backend server
Store your API key securely on your server
Authenticate users before generating verification IDs

❌ Don't

Include your API key in your mobile app
Call the verification API directly from your app
Commit API keys to version control

Troubleshooting

Camera permissions not working

Android: Check minSdkVersion 21 or higher, run flutter clean
iOS: Add camera usage descriptions to Info.plist

WebView not loading

Ensure you have internet permission
Check that the base URL is correct
Enable debug mode to see detailed logs

Verification fails to start

Verify the verification ID is valid and not expired
Check your backend is generating IDs correctly
Ensure your API key is valid

Additional Resources

GitHub Repository

Source code, examples, and issue tracker

Complete README

Full documentation with examples

Backend Integration Guide

Node.js, Python, PHP examples with webhooks

Example App

Working Flutter application demonstrating SDK usage