Flutter 身份验证 SDK：Dart 移动端 KYC

flutter pub add didit_sdk

dependencies:
  didit_sdk: ^4.13.2

flutter pub get

dependencies:
  didit_sdk_core: ^4.13.2

# Pick one: 'all', 'core', 'autodetection', 'nfc'
$DiditSdkIosVariant = 'all'

didit_sdk_ios_deployment_target = ['all', 'nfc'].include?($DiditSdkIosVariant) ? '15.0' : '13.0'
platform :ios, didit_sdk_ios_deployment_target

didit_sdk_ios_pod = case $DiditSdkIosVariant
                    when 'all' then 'DiditSDK/All'
                    when 'core' then 'DiditSDK/Core'
                    when 'autodetection' then 'DiditSDK/AutoDetection'
                    when 'nfc' then 'DiditSDK/NFC'
                    end
didit_sdk_ios_podspec = 'https://raw.githubusercontent.com/didit-protocol/sdk-ios/4.13.2/DiditSDK.podspec'

target 'Runner' do
  use_frameworks!

  pod didit_sdk_ios_pod, :podspec => didit_sdk_ios_podspec

  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
end

post_install do |installer|
  installer.pods_project.targets.each do |target|
    flutter_additional_ios_build_settings(target)
    target.build_configurations.each do |config|
      config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = didit_sdk_ios_deployment_target
    end
  end
end

diditSdkAndroidNfcEnabled=false

android {
    packaging {
        resources {
            pickFirsts += "META-INF/versions/9/OSGI-INF/MANIFEST.MF"
        }
    }
}

<key>com.apple.developer.nfc.readersession.iso7816.select-identifiers</key>
<array>
    <string>D23300000045737445494420763335</string>
    <string>A0000002471001</string>
    <string>A0000002472001</string>
    <string>00000000000000</string>
    <string>D392F000260100000001</string>
</array>

<key>com.apple.developer.nfc.readersession.formats</key>
<array>
    <string>TAG</string>
</array>

import 'package:didit_sdk/sdk_flutter.dart';

// Start verification with a session token from your backend
final result = await DiditSdk.startVerification('your-session-token');

switch (result) {
  case VerificationCompleted(:final session):
    if (session.status == VerificationStatus.approved) {
      print('Identity verified!');
    }
  case VerificationCancelled():
    print('User cancelled');
  case VerificationFailed(:final error):
    print('Error: ${error.message}');
}

import 'package:didit_sdk/sdk_flutter.dart';

// Your backend creates a session and returns the token
final sessionToken = await yourBackend.createVerificationSession(userId);

// Pass the token to the SDK
final result = await DiditSdk.startVerification(sessionToken);

import 'package:didit_sdk/sdk_flutter.dart';

final result = await DiditSdk.startVerificationWithWorkflow(
  'your-workflow-id',
  vendorData: 'user-123',
  config: const DiditConfig(loggingEnabled: true),
);

final result = await DiditSdk.startVerification(
  'your-session-token',
  config: const DiditConfig(
    languageCode: 'es',       // Force Spanish language
    showLanguageSelector: true, // Let the user change language
    fontFamily: 'Avenir',     // Custom font
    loggingEnabled: true,     // Enable debug logging
  ),
);

final result = await DiditSdk.startVerificationWithWorkflow(
  'your-workflow-id',
  vendorData: 'user-123',
  config: const DiditConfig(
    languageCode: 'es',
    showLanguageSelector: true,
    loggingEnabled: true,
  ),
);

config: const DiditConfig(
  defaultLivenessCamera: CameraLens.back,
  showLivenessCameraSwitchButton: false,
),

// Use device locale (default)
await DiditSdk.startVerification(token);

// Force specific language
await DiditSdk.startVerification(token,
  config: const DiditConfig(languageCode: 'fr'),
);

// Let the user change language on the welcome screen
await DiditSdk.startVerification(token,
  config: const DiditConfig(showLanguageSelector: true),
);

// Your backend handles the full session creation:
// POST /v3/session/ with contact_details, expected_details, metadata, etc.
final sessionToken = await yourBackend.createSession(userId);

// The SDK only needs the token
final result = await DiditSdk.startVerification(sessionToken);

import 'package:didit_sdk/sdk_flutter.dart';

Future<void> verify(String token) async {
  final result = await DiditSdk.startVerification(token);

  switch (result) {
    case VerificationCompleted(:final session):
      switch (session.status) {
        case VerificationStatus.approved:
          print('Approved! Session: ${session.sessionId}');
          // User is verified — grant access
        case VerificationStatus.pending:
          print('Under review. Session: ${session.sessionId}');
          // Show "verification in progress" UI
        case VerificationStatus.declined:
          print('Declined. Session: ${session.sessionId}');
          // Handle declined verification
      }

    case VerificationCancelled(:final session):
      print('User cancelled.');
      if (session != null) {
        print('Session: ${session.sessionId}');
      }
      // Maybe show retry option

    case VerificationFailed(:final error):
      print('Error [${error.type}]: ${error.message}');
      // Handle error — show retry or contact support
  }
}

// Node.js / Express example. Run on your server. NEVER ship DIDIT_API_KEY to the device.
import express from "express";

const app = express();
app.use(express.json());

app.post("/api/verification/start", async (req, res) => {
  const response = await fetch("https://verification.didit.me/v3/session/", {
    method: "POST",
    headers: {
      "x-api-key": process.env.DIDIT_API_KEY!,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      workflow_id: process.env.DIDIT_WORKFLOW_ID,
      vendor_data: req.body.userId, // your stable user id
    }),
  });

  if (!response.ok) {
    return res.status(500).json({ error: `Didit ${response.status}` });
  }

  const { session_id, session_token } = await response.json();
  // Persist session_id <-> userId so you can match the webhook later.
  res.json({ session_id, session_token });
});

import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'package:didit_sdk/sdk_flutter.dart';

class VerifyButton extends StatefulWidget {
  const VerifyButton({super.key, required this.userId});
  final String userId;

  @override
  State<VerifyButton> createState() => _VerifyButtonState();
}

class _VerifyButtonState extends State<VerifyButton> {
  bool _loading = false;

  Future<void> _verify() async {
    setState(() => _loading = true);
    try {
      final resp = await http.post(
        Uri.parse('https://your-backend.example.com/api/verification/start'),
        headers: const {'Content-Type': 'application/json'},
        body: jsonEncode({'userId': widget.userId}),
      );
      final sessionToken = (jsonDecode(resp.body) as Map)['session_token'] as String;

      final result = await DiditSdk.startVerification(sessionToken);

      switch (result) {
        case VerificationCompleted(:final session):
          if (session.status == VerificationStatus.approved) {
            // Optimistic UI; rely on the webhook delivered to your backend as the source of truth.
          }
        case VerificationCancelled():
          // User dismissed the flow
          break;
        case VerificationFailed(:final error):
          // Show retry — error.type / error.message
          break;
      }
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      onPressed: _loading ? null : _verify,
      child: Text(_loading ? 'Starting...' : 'Verify identity'),
    );
  }
}

app.post("/api/webhooks/didit", express.raw({ type: "application/json" }), (req, res) => {
  // 1. Verify the X-Signature header (see Webhooks docs)
  // 2. Parse the body
  const event = JSON.parse(req.body.toString());
  if (event.webhook_type === "status.updated") {
    // event.session_id, event.status ("Approved" | "Declined" | "In Review" | ...)
    // Look up the user by session_id and update their verification state.
  }
  res.sendStatus(200);
});

import 'package:flutter/material.dart';
import 'package:didit_sdk/sdk_flutter.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Didit SDK Example',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: const Color(0xFF1A1A1A)),
        useMaterial3: true,
      ),
      home: const VerificationScreen(),
    );
  }
}

class VerificationScreen extends StatefulWidget {
  const VerificationScreen({super.key});

  @override
  State<VerificationScreen> createState() => _VerificationScreenState();
}

class _VerificationScreenState extends State<VerificationScreen> {
  final _tokenController = TextEditingController();
  bool _loading = false;

  @override
  void dispose() {
    _tokenController.dispose();
    super.dispose();
  }

  Future<void> _startVerification() async {
    final token = _tokenController.text.trim();
    if (token.isEmpty) {
      _showAlert('Error', 'Please enter a session token.');
      return;
    }

    setState(() => _loading = true);

    try {
      final result = await DiditSdk.startVerification(
        token,
        config: const DiditConfig(loggingEnabled: true),
      );

      switch (result) {
        case VerificationCompleted(:final session):
          _showAlert(
            'Verification Complete',
            'Status: ${session.status.name}\nSession: ${session.sessionId}',
          );
        case VerificationCancelled():
          _showAlert('Cancelled', 'The user cancelled the verification.');
        case VerificationFailed(:final error):
          _showAlert('Failed', '${error.type.name}: ${error.message}');
      }
    } catch (e) {
      _showAlert('Error', 'Unexpected error: $e');
    } finally {
      setState(() => _loading = false);
    }
  }

  void _showAlert(String title, String message) {
    showDialog(
      context: context,
      builder: (ctx) => AlertDialog(
        title: Text(title),
        content: Text(message),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx),
            child: const Text('OK'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SafeArea(
        child: Padding(
          padding: const EdgeInsets.all(24),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              TextField(
                controller: _tokenController,
                decoration: InputDecoration(
                  hintText: 'Enter session token...',
                  border: OutlineInputBorder(
                    borderRadius: BorderRadius.circular(8),
                  ),
                ),
                autocorrect: false,
              ),
              const SizedBox(height: 16),
              ElevatedButton(
                onPressed: _loading ? null : _startVerification,
                style: ElevatedButton.styleFrom(
                  backgroundColor: const Color(0xFF1A1A1A),
                  foregroundColor: Colors.white,
                  padding: const EdgeInsets.symmetric(vertical: 16),
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(8),
                  ),
                ),
                child: _loading
                    ? const SizedBox(
                        height: 20,
                        width: 20,
                        child: CircularProgressIndicator(
                          strokeWidth: 2,
                          color: Colors.white,
                        ),
                      )
                    : const Text(
                        'Start Verification',
                        style: TextStyle(fontWeight: FontWeight.w600),
                      ),
              ),
            ],
          ),
        ),
      ),
    );
  }
}