How to protect a user who wants to match their face with before taking pictures on their mobile

[tariqul000]

Suppose I have an attendance app where the user can give attendance with the face but someone can take her picture and give attendance every time, without being present there.

[moisesmember]

Eu criei essa classe para me atender nisso

`

import 'dart:convert';
import 'package:flutter/foundation.dart';
import 'package:http/http.dart';

class Api{
  static const urlPrefix = 'http://xx.xx.xx.xx:port/router';
  final resultNotifier = ValueNotifier<RequestState>(RequestInitial());

  Future<dynamic> makeGetRequest(String router) async {
      resultNotifier.value = RequestLoadInProgress();
      final headers = {"Content-type": "application/json",
                       "Authorization": "bearer"};
      final url = Uri.parse('$urlPrefix/$router');
      Response response = await get(url, headers: headers);
      print('Status code: ${response.statusCode}');     
      return _handleResponse(response);
    }

Future<dynamic> makePostRequest(String router, String body) async {
  resultNotifier.value = RequestLoadInProgress();
  final url = Uri.parse('$urlPrefix/$router');
  final headers = {"Content-type": "application/json",
    "Authorization": "bearer"};
  final response = await post(url, headers: headers, body: body);   
  print('Status code: ${response.statusCode}');
  print('Body: ${response.body}');
  return _handleResponse(response);
}

Future<void> makePutRequest() async {
  resultNotifier.value = RequestLoadInProgress();
  final url = Uri.parse('$urlPrefix/posts/1');
  final headers = {"Content-type": "application/json"};
  final json = '{"title": "Hello", "body": "body text", "userId": 1}';
  final response = await put(url, headers: headers, body: json);
  print('Status code: ${response.statusCode}');
  print('Body: ${response.body}');
  _handleResponse(response);
}

Future<void> makePatchRequest() async {
  resultNotifier.value = RequestLoadInProgress();
  final url = Uri.parse('$urlPrefix/posts/1');
  final headers = {"Content-type": "application/json"};
  final json = '{"title": "Hello"}';
  final response = await patch(url, headers: headers, body: json);
  print('Status code: ${response.statusCode}');
  print('Body: ${response.body}');
  _handleResponse(response);
}

Future<void> makeDeleteRequest() async {
  resultNotifier.value = RequestLoadInProgress();
  final url = Uri.parse('$urlPrefix/posts/1');
  final response = await delete(url);
  print('Status code: ${response.statusCode}');
  print('Body: ${response.body}');
  _handleResponse(response);
}

dynamic _handleResponse(Response response){
    if (response.statusCode >= 400) {
      return  [{}] ;
    } else {
      return json.decode( response.body );
    }
  }

}

class RequestState {
  const RequestState();
}

class RequestInitial extends RequestState {}
class RequestLoadInProgress extends RequestState {}
class RequestLoadSuccess extends RequestState {
  const RequestLoadSuccess(this.body);
  final String body;
}

class RequestLoadFailure extends RequestState {}

`