dart
复制代码
class HttpHelper {
static Dio? mDio;
static BaseOptions? options;
static HttpHelper? httpHelper;
CancelToken cancelToken = CancelToken();
static const String GET = 'get';
static const String POST = 'post';
static const String PUT = 'put';
static const String PATCH = 'patch';
static const String DELETE = 'delete';
static HttpHelper? get instance => getInstance();
static Dio? get dio => getDio();
static HttpHelper? getInstance() {
httpHelper ??= HttpHelper();
return httpHelper;
}
static Dio? getDio() {
final token = GetStorage().read('token');
final Map<String, dynamic> headerMap = {};
if (token != null) {
headerMap.putIfAbsent("Authorization", () => "Bearer $token");
}
options = BaseOptions(
//请求基地址,可以包含子路径
baseUrl: Api.BASE_URL,
//连接服务器超时时间，单位是毫秒.
connectTimeout: const Duration(seconds: 10),
//2.x中为接收数据的最长时限
receiveTimeout: const Duration(seconds: 5),
//Http请求头.
headers: headerMap,
// 请求的Content-Type，默认值是"application/json; charset=utf-8".
// /// 如果您想以"application/x-www-form-urlencoded"格式编码请求数据,
// /// 可以设置此选项为 `Headers.formUrlEncodedContentType`, 这样[Dio]
// /// 就会自动编码请求体.
contentType: Headers.jsonContentType,
/// [responseType] 表示期望以那种格式(方式)接受响应数据。
/// 目前 [ResponseType] 接受三种类型 `JSON`, `STREAM`, `PLAIN`.
///
/// 默认值是 `JSON`, 当响应头中content-type为"application/json"时，dio 会自动将响应内容转化为json对象。
/// 如果想以二进制方式接受响应数据，如下载一个二进制文件，那么可以使用 `STREAM`.
///
/// 如果想以文本(字符串)格式接收响应数据，请使用 `PLAIN`.
responseType: ResponseType.json,
);
mDio = Dio(options);
mDio?.interceptors.add(interceptorsWrapper());
mDio?.httpClientAdapter = IOHttpClientAdapter(
createHttpClient: () {
final client = HttpClient();
// Config the client.
client.findProxy = (uri) {
// Forward all request to proxy "localhost:8888".
// Be aware, the proxy should went through you running device,
// not the host platform.
return 'PROXY 192.168.0.191:8089';
};
// You can also create a new HttpClient for Dio instead of returning,
// but a client must being returned here.
return client;
},
);
return mDio;
}
static InterceptorsWrapper interceptorsWrapper() {
return InterceptorsWrapper(onRequest: (options, handler) {
// Do something before request is sent
return handler.next(options); //continue
// 如果你想完成请求并返回一些自定义数据，你可以resolve一个Response对象 `handler.resolve(response)`。
// 这样请求将会被终止，上层then会被调用，then中返回的数据将是你的自定义response.
//
// 如果你想终止请求并触发一个错误,你可以返回一个`DioError`对象,如`handler.reject(error)`，
// 这样请求将被中止并触发异常，上层catchError会被调用。
}, onResponse: (response, handler) {
// Do something with response data
return handler.next(response); // continue
// 如果你想终止请求并触发一个错误,你可以 reject 一个`DioError`对象,如`handler.reject(error)`，
// 这样请求将被中止并触发异常，上层catchError会被调用。
}, onError: (DioError e, handler) {
// Do something with response error
if (e.response != null) {
if (e.response?.statusCode == 401) {
ToastMsg.show("当前登录已过期，请重新登录！");
Future.delayed(const Duration(milliseconds: 1000), () {
Get.offAllNamed(AppRoutes.LOGIN);
});
} else if (e.response?.statusCode == 403) {
ToastMsg.show("暂无权限访问，请联系管理员！");
} else {
ToastMsg.show("系统内部异常！");
}
}
return handler.next(e); //continue
// 如果你想完成请求并返回一些自定义数据，可以resolve 一个`Response`,如`handler.resolve(response)`。
// 这样请求将会被终止，上层then会被调用，then中返回的数据将是你的自定义response.
});
}
///Get请求
Future<BaseRes<T>> getHttp<T>(String url, parameters,{loading = true}) async {
return await getResponse<T>(url, method: GET, parameters: parameters,loading:loading);
}
Future<BaseRes<T>> postHttp<T>(String url, parameters,{loading = true}) async {
///定义请求参数
parameters = parameters ?? <String, dynamic>{};
return await getResponse<T>(url, method: POST, parameters: parameters,loading:loading);
}
Future<BaseRes<T>> putHttp<T>(String url, parameters,{loading = true}) async {
///定义请求参数
parameters = parameters ?? <String, dynamic>{};
return await getResponse<T>(url, method: PUT, parameters: parameters,loading:loading);
}
Future<BaseRes<T>> deleteHttp<T>(String url, parameters,{loading = true}) async {
///定义请求参数
parameters = parameters ?? <String, dynamic>{};
return await getResponse<T>(url, method: DELETE, parameters: parameters,loading:loading);
}
/*
* 下载文件
*/
downloadFile(urlPath, savePath, onReceiveProgress) async {
Response? response;
try {
response = await dio?.download(urlPath, savePath,
onReceiveProgress: onReceiveProgress);
} on DioError catch (e) {
formatError(e);
}
return response?.data;
}
Future<BaseRes<T>> getResponse<T>(
String url, {
required String method,
parameters,
loading,
}) async {
//这里指定response自动转成map,不指定的话有可能是String类型
Response<Map<String, dynamic>>? response;
if(loading) {
ToastMsg.showLoading();
}
switch (method) {
case GET:
response = await dio?.get(url,
queryParameters: parameters ?? <String, dynamic>{});
break;
case PUT:
response = await dio?.put(url,
queryParameters: parameters ?? <String, dynamic>{});
break;
case DELETE:
response = await dio?.delete(url,
queryParameters: parameters ?? <String, dynamic>{});
break;
default:
response =
await dio?.post(url, data: parameters ?? <String, dynamic>{});
break;
}
if(loading) {
ToastMsg.cancelLoading();
}
//200代表网络请求成功
if (response?.statusCode == 200) {
/// 将后台的data字段转成自己想要的数据/数据集,code根据后端实际返回进行判断访问结果
BaseRes<T> bean = BaseRes.fromJson(response?.data);
return bean;
} else if (response?.statusCode == 401) {
ToastMsg.show("当前登录已过期，请重新登录！");
Future.delayed(const Duration(milliseconds: 1000), () {
Get.offAllNamed(AppRoutes.LOGIN);
});
} else if (response?.statusCode == 403) {
ToastMsg.show("暂无权限访问，请联系管理员！");
} else {
ToastMsg.show("系统内部异常！");
}
throw Exception('${response?.statusCode}+${response?.statusMessage}');
}
void formatError(DioError e) {
print(e.message);
}
/*
* 取消请求
* 同一个cancel token 可以用于多个请求，当一个cancel token取消时，所有使用该cancel token的请求都会被取消。
*/
void cancelRequests(CancelToken token) {
token.cancel("cancelled");
}
}