如何在 Flutter 中使用 JSON 正文发出 http DELETE 请求？

Question

In flutter project, I want to perform a DELETE request with JSON body. But whenever I am trying to use http.delete method it is showing me - The named parameter 'body' isn't defined.

Here's the example of my API delete request-

url: 'BASE_URL'+notes/delete;

Header:

Content-Type : 'application/json',

token: 'my token',

jwt: ' my jwt'

Body:

{

        "id":"4"

}

Response:

status: "Deleted"

So, I need to make the regarding DELETE request with the following body and headers mentioned above and from the JSON response I need to save the value of status in a String. Here, I need a help with the code to make this delete request.

Please inform the entire procedure to make the DELETE request and getting response in the above mentioned way.

Answer 1

You can use Request from http package:

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

Future<String> deleteWithBodyExample() async {
  final baseUrl = "baseUrl";
  final url = Uri.parse(baseUrl + "notes/delete");
  final request = http.Request("DELETE", url);
  request.headers.addAll(<String, String>{
    "Accept": "application/json",
    "token": "my token",
    "jwt" : "my jwt"
  });
  request.body = jsonEncode({"id": 4});
  final response = await request.send();
  if (response.statusCode != 200)
    return Future.error("error: status code ${response.statusCode}");
  return await response.stream.bytesToString();
}

Answer 2

Short answer:

A http delete request does not support a body. Normally you just use an identifier in your url to identify the object to delete like this :

DELETE api.com/entity/1234

1234 is the ID of the object.

Long answer :

In your case you want to make a POST request to that url.

There is a dart package that provides some helper classes for http requests.

Github : https://github.com/Ephenodrom/Dart-Basic-Utils Install it with:

dependencies:
  basic_utils: ^1.4.0

Usage

Map<String, String> headers = {
  "Accept": "application/json",
  "token": "my-token", 
  "jwt" : "my-jwt" 
};

String URL = BASE_URL+"notes/delete" ;

String body = "{\"id\":\"4\"}" 
Map<String, dynamic> dataAsJson = await HttpUtils.postForJson(url,body,
      headers: headers);

Additional information :

These are all methods from the HttpUtils class.

Future<Map<Response> getForFullResponse(String url,{Map<String, dynamic> queryParameters,Map<String, String> headers});
Future<Map<String, dynamic>> getForJson(String url,{Map<String, dynamic> queryParameters,Map<String, String> headers});
Future<String> getForString(String url,{Map<String, dynamic> queryParameters,Map<String, String> headers});
Future<Map<Response> postForFullResponse(String url, String body,{Map<String, String> queryParameters,Map<String, String> headers});
Future<Map<String, dynamic>> postForJson(String url, String body,{Map<String, String> queryParameters,Map<String, String> headers});
Future<String> postForString(String url, String body,{Map<String, String> queryParameters,Map<String, String> headers});
Future<Response> putForFullResponse(String url, String body,{Map<String, String> queryParameters,Map<String, String> headers});
Future<Map<String, dynamic>> putForJson(String url, String body,{Map<String, String> queryParameters,Map<String, String> headers});
Future<String> putForString(String url, String body,{Map<String, String> queryParameters,Map<String, String> headers});
Future<Response deleteForFullResponse(String url,{Map<String, String> queryParameters,Map<String, String> headers});
Future<Map<String, dynamic>> deleteForJson(String url,{Map<String, String> queryParameters,Map<String, String> headers});
Future<String> deleteForString(String url,{Map<String, String> queryParameters,Map<String, String> headers});
Map<String, dynamic> getQueryParameterFromUrl(String url);
String addQueryParameterToUrl(String url, Map<String, dynamic> queryParameters);