在Flutter開發(fā)過程中勢必要用到網(wǎng)絡(luò)請求，在Flutter插件庫中有Http、Dio等很多優(yōu)秀的框架，個(gè)人比較喜歡用Dio請求框架
在此總結(jié)下自己的封裝經(jīng)驗(yàn)
Dio對象在App請求中一般使用一個(gè)，如有特殊需求會(huì)使用多個(gè)，在此使用單例模式。
import 'package:dio/dio.dart';
import 'package:loxen/api/intercept.dart';
import 'package:loxen/utils/config.dart';
class BaseNetWork {
// 工廠模式
factory BaseNetWork() => _getInstance();
static BaseNetWork get instance => _getInstance();
static BaseNetWork _instance;
Dio dio;
BaseOptions options;
BaseNetWork._internal() {
dio = Dio()
..options = BaseOptions(
baseUrl: Constants.BASE_URL,
connectTimeout: 10000,
receiveTimeout: 1000 * 60 * 60 * 24,
responseType: ResponseType.json,
headers: {"Content-Type": "application/json"})
//網(wǎng)絡(luò)狀態(tài)攔截
..interceptors.add(AuthInterceptor())
..interceptors.add(HttpLog())
..interceptors.add(ErrorInterceptor());
}
static BaseNetWork _getInstance() {
if (_instance == null) {
_instance = new BaseNetWork._internal();
}
return _instance;
}
}
這里對創(chuàng)建Dio對象，進(jìn)行了些基礎(chǔ)配置，添加了些請求攔截器
AuthInterceptor：主要作用在請求內(nèi)加入http中header的信息：
class AuthInterceptor extends Interceptor {
@override
Future onRequest(RequestOptions options) async {
String accessToken = await SharedPreferencesUtil.getData(Constants.ACCESS_TOKEN);
if (accessToken != null && accessToken != '') {
options.headers['content-type'] = 'application/json;charset=utf-8';
options.headers['Authorization'] = 'JWT $accessToken';
}
return super.onRequest(options);
}
}
HttpLog:是對請求過程中的參數(shù)和返回值參數(shù)進(jìn)行打?。?/p>
class HttpLog extends Interceptor{
@override
Future onRequest(RequestOptions options) {
print("\n ---------Start Http Request---------");
print("Request_BaseUrl:${options.baseUrl}");
print("Request_Path:${options.path}");
print("Request_Method:${options.method}");
print("Request_Headers:${options.headers}");
print("Request_Data:${options.data}");
print("Request_QueryParameters:${options.queryParameters}");
print("---------End Http Request---------");
return super.onRequest(options);
}
@override
Future onResponse(Response response) {
print("---------Start Http Response---------");
print("Response_BaseUrl:${response.request.baseUrl}");
print("Response_Path:${response.request.path}");
print("Response_StatusCode:${response.statusCode}");
print("Response_StatusMessage:${response.statusMessage}");
print("Response_Headers:${response.headers.toString()}");
print("---------End Http Response---------");
return super.onResponse(response);
}
}
ErrorInterceptor:這里是對登錄的Token做了些刷新處理
class ErrorInterceptor extends Interceptor {
@override
onError(DioError error) async {
print(error);
//判讀異常狀態(tài) 401未登錄過期或者未登錄狀態(tài)的異常
if (error.response != null && error.response.statusCode == 401) {
String token = await SharedPreferencesUtil.getData(Constants.ACCESS_TOKEN);//獲取本地存儲(chǔ)的Token
if (token != null && token.trim() != '') {//Token存在則說明Token過期需要刷新，否則是未登錄狀態(tài)不做處理
Dio dio = BaseNetWork.instance.dio;//獲取應(yīng)用的Dio對象進(jìn)行鎖定 防止后面請求還是未登錄狀態(tài)下請求
dio.lock();
String accessToken = await getToken();//重新獲取Token
dio.unlock();
if (accessToken != '') {
Dio tokenDio2 = new Dio(BaseNetWork.instance.dio.options); //創(chuàng)建新的Dio實(shí)例
var request = error.request;
request.headers['Authorization'] = 'JWT $accessToken';
var response = await tokenDio2.request(request.path,
data: request.data,
queryParameters: request.queryParameters,
cancelToken: request.cancelToken,
options: request,
onReceiveProgress: request.onReceiveProgress);
return response;
}
}
}
super.onError(error);
}
Future<String> getToken() async {
//獲取當(dāng)前的refreshToken，一般后臺(tái)會(huì)在登錄后附帶一個(gè)刷新Token用的reToken
String refreshToken =
await SharedPreferencesUtil.getData(Constants.REFRESH_TOKEN);
//因?yàn)锳pp單例的Dio對象已被鎖定，所以需要?jiǎng)?chuàng)建新的Dio實(shí)例
Dio tokenDio = new Dio(BaseNetWork.instance.dio.options);
Map<String, String> map = {
"rft": refreshToken,
}; //設(shè)置當(dāng)前的refreshToken
try {
//發(fā)起請求，獲取Token
var response = await tokenDio.post("/api/v1/user/refresh_token", data: map);
if (response.statusCode == 201) {
LoginBean loginbean = LoginBean.fromJson(response.data);
SharedPreferencesUtil.putData(Constants.ACCESS_TOKEN, loginbean.data.token);
if (loginbean.data.rft != null && loginbean.data.rft.trim() != '') {
SharedPreferencesUtil.putData(Constants.REFRESH_TOKEN, loginbean.data.rft);
}
return loginbean.data.token;
}
return '';
} on DioError catch (e) {
print("Token刷新失敗:$e");
SharedPreferencesUtil.putData(Constants.ACCESS_TOKEN, '');
SharedPreferencesUtil.putData(Constants.REFRESH_TOKEN, '');
return '';
}
}
}
之后就可以通過單例對象直接調(diào)用Dio對象發(fā)起 請求。
后面則需要將我們業(yè)務(wù)所需的ApiUrl在進(jìn)行一次調(diào)用封裝，返回值解析等等操作，在操作Dio過程中將業(yè)務(wù)和UI邏輯進(jìn)行很好的分離。
mixin LikeMixin {
Stream<LikeList> userLikes(
{String userId = '0', String page = '1', String pageSize}) {
return ApiService.userLikes(userId, page, pageSize)
.flatMap((value) => compute(decodeLikeList, value.data).asStream())
.flatMap((value) => Stream.value(value.data));
}
Stream<int> likeComment(String id) {
return ApiService.likeComment(id)
.flatMap((value) => Stream.value(value.statusCode));
}
Stream<int> unLikeComment(String id) {
return ApiService.unLikeComment(id)
.flatMap((value) => Stream.value(value.statusCode));
}
Stream<Like> like(String type, String id) {
return ApiService.likeSomething(type, id)
.flatMap((value) => compute(decodeLikeBean, value.data).asStream())
.flatMap((value) => Stream.value(value.data));
}
Stream<Like> unLike(String type, String id) {
return ApiService.unLikeSomething(type, id)
.flatMap((value) => compute(decodeLikeBean, value.data).asStream())
.flatMap((value) => Stream.value(value.data));
}
static BaseMode<LikeList> decodeLikeList(dynamic json) {
return BaseMode<LikeList>(json);
}
static BaseMode<Like> decodeLikeBean(dynamic json) {
return BaseMode<Like>(json);
}
}
