command_network

What

command_network is a high level request util based on dio, inspired by YTKNetowrk.

Features

• Plugin mechanism, handle request start and finish.
• Support HTTP authentication(Basic/Digest)

Getting started

Add dependency

dependencies:
  command_network: ^0.0.1

A simple example:

var api = GetUserInfoApi();
Result result = await api.start();
if (result.isSuccess) {
  print('[Result]sucess: ${result.data}');
} else {
  print('[Result]failed: ${result.error}');
}

Usage

command_network's basic composition

command_netwrok mainly contains the following classes:

• NetworkConfig: it's used for setting global network host address.
• BaseRequest: it's the parent of all the detailed network request classes. All netwrok request classes should inherit it. Every subclass of BaseRequest represents a specific network request.

NetworkConfig class

Network class has 1 main usages for now:

1. Set global network host address.

Setting global network host address using NetworkConfig is according to the Do Not Repeat Yourself principle, we should write the host address only once.

We should set NetworkConfig's property at the begining of app launching, the sample is below:

void main() {
  NetworkConfig().baseUrl = 'https://sample.com';
  runApp(const MyApp());
}

After setting, all network requests will use NetworkConfig's baseUrl property as their host address by default. You can overwrite the baseUrl method in request implementation to change it for specific request, too.

BaseRequest class

The design idea of BaseRequest is that every specific network request should be a object. So after using command_network, all your request classes should inherit BaseRequest. Through overwriting the methods of super class, you can build your own specific and distinguished request. The key idea behind this is somewhat like the Command Pattern.

For example, if we want to send a POST request to https://sample.com/api/login, with username and password as arguments, then the class should be as following:

import 'dart:convert';

import 'package:crypto/crypto.dart';

import 'package:command_network/command_network.dart';


class LoginApi extends BaseRequest {
  LoginApi(this.username, this.password);

  String username;
  String password;

  @override
  HttpRequestMethod get requestMethod => HttpRequestMethod.post;

  @override
  Map<String, dynamic>? get requestArgument {
    var md5Password = md5.convert(utf8.encode(password));
    Map<String, dynamic> bodyMap = {};
    bodyMap['username'] = username;
    bodyMap['password'] = md5Password;
    return bodyMap;
  }

  @override
  String get requestUrl {
    return 'api/login';
  }

}

In above example:

• Through overwriting requestUrl method, we've indicated the detail url. Because host address has been set in NetworkConfig, we should not write the host address in requestUrl method.
• Through overwriting requestMethod method, we've indicated the use of the POST method.
• Through overwriting requestArgument method, we've provided the POST data.

Call LoginApi

How can we use the LoginApi? We can call it in the login page. After initializing the instance, we can call its start() method to send the request. Then we can get network response by a Result object.

ElevatedButton(
  onPressed: () async {
    var loginApi = LoginApi('username', 'password');
    Result result = await loginApi.start();
    if (result.isSuccess) {
      print('[Result]sucess: ${result.data}');
    } else {
      print('[Result]failed: ${result.error}');
    }
  }
  child: const Text("Login"),
)

Since I am not used to use try-catch, so all exceptions will be handled inside start() method. You just need to check the isSucess property of Result class to verify if the request is sucessful or not. If the request failed, use error property of the Result class to figure out the reason.

Acknowledgements

• dio Thanks for their great work.

License

command_network is available under the BSD 3-Clause.

Libraries

command_network