So i’m creating a simple agenda app, the thing is i have two options once i’m looking for all the contacts, the do appear and they are written into a database and a backend created with Google Apps Script. Once i do the backup the data is written into the “database”(Which is currently just a Google Sheets doc) but once i try to recover it, to be shown in the app theres just errors, i have this for the backend:

import 'package:http/http.dart' as http;
import 'package:logger/logger.dart';

class BackendHelper {
  static const String _server = "script.google.com";
  static Logger logger = Logger();

  static Future<int> sendData(String jsonData) async {
    var client = http.Client();
    int code = -1;
    try {
      var response = await client.post(
        Uri.https(_server, "macros/s/AKfycby3g-CRk53h4Rr07VWxJr4d6CYm33_-cft8nOeIlwAuOFwAjzMz6jDamo_HHxpFtTz-/exec"),
        body: {'acc': '2', 'tbl': 'Contacts', 'data': jsonData},
      );
      code = response.statusCode;
      logger.i(response.statusCode);
    } finally {
      client.close();
    }
    return code;
  }

  static Future<String> getData() async {
    var client = http.Client();
    String responseBody = '';
    try {
      var response = await client.get(
        Uri.https(_server, "macros/s/AKfycby3g-CRk53h4Rr07VWxJr4d6CYm33_-cft8nOeIlwAuOFwAjzMz6jDamo_HHxpFtTz-/exec"),
        headers: {'acc': '1', 'tbl': 'Contacts'},
      );
      if (response.statusCode == 200) {
        if (response.headers['content-type']?.contains('application/json') == true) {
          responseBody = response.body;
          logger.i('Data retrieved successfully');
        } else {
          logger.e('Expected JSON but got ${response.headers['content-type']}');
          responseBody = 'Invalid response: Expected JSON';
        }
      } else {
        logger.e('Failed to retrieve data. Status code: ${response.statusCode}');
        responseBody = 'Error: ${response.statusCode}';
      }
    } finally {
      client.close();
    }
    return responseBody;
  }
}

Here’s the one that backups the data into the database:

static Future<int> sendData(String jsonData) async {
    var client = http.Client();
    int code = -1;
    try {
      var response = await client.post(
        Uri.https(_server, "macros/s/AKfycby3g-CRk53h4Rr07VWxJr4d6CYm33_-cft8nOeIlwAuOFwAjzMz6jDamo_HHxpFtTz-/exec"),
        body: {'acc': '2', 'tbl': 'Contacts', 'data': jsonData},
      );
      code = response.statusCode;
      logger.i(response.statusCode);
    } finally {
      client.close();
    }
    return code;
  }

Is asking for the JSON created for the data that’s backedup, but it’s not able to retrieve ir back. In the logger shows this.

Expected JSON but got text/html; charset=utf-8
I/flutter (11811): │ #0   _ContactListWidgetState.recoverContacts 
I/flutter (11811): │ #1   <asynchronous suspension>
I/flutter (11811): 
Failed to parse JSON: FormatException: Unexpected character (at 
Invalid response: Expected JSON

I have this option for the button here:

Future<void> recoverContacts() async {
var response = await BackendHelper.getData();

try {
  List<dynamic> recoveredContacts = json.decode(response);

  ContactProvider conProv = ContactProvider();
  await conProv.open("ContactsDB");
  await conProv.deleteAllContacts();

  for (var contactData in recoveredContacts) {
    Contact contact = Contact(
      name: contactData['name'],
      phone: contactData['phone'],
      email: contactData['email'],
    );
    await conProv.insert(contact);
  }

  await conProv.close();
  await loadAllContacts();

  var snackBar = const SnackBar(
    content: Text('Contactos recuperados exitosamente.'),
  );
  ScaffoldMessenger.of(context).showSnackBar(snackBar);

  logger.i("RECOVER CONTACTS FINISHED.");
} catch (e) {
  logger.e('Failed to parse JSON: $e');
  var snackBar = const SnackBar(
    content: Text('Error recuperando contactos: Formato de datos incorrecto.'),
  );
  ScaffoldMessenger.of(context).showSnackBar(snackBar);
}

Appreciate any help!