What is the purpose and features of the HTTP PATCH method?

The HTTP PATCH method is used for partial updates of a resource on the server. Unlike PUT, which usually replaces the entire resource, PATCH allows sending only the fields that need to be changed.

Features of PATCH:

• Partial update: only specified fields are changed.
• Idempotency is not guaranteed, unlike PUT.
• The request body contains instructions for modification, often in JSON format.

Example of usage in Flutter with the http package:

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

Future<void> updateUserName(String userId, String newName) async {
  final url = Uri.parse('https://api.example.com/users/$userId');
  final response = await http.patch(
    url,
    headers: {'Content-Type': 'application/json'},
    body: '{"name": "$newName"}',
  );
  if (response.statusCode == 200) {
    print('User updated successfully');
  } else {
    print('Failed to update user');
  }
}