WebApiClient.JIT的netcoreapp版本,集高性能高可扩展性于一体的声明式http客户端库,特别适用于微服务的restful资源请求,也适用于各种畸形http接口请求。
<PackageReference Include="WebApiClientCore" Version="1.0.0-beta*" />
使用MockResponseHandler消除真实http请求,原生HttpClient、WebApiClientCore和Refit的性能参考:
BenchmarkDotNet=v0.12.1, OS=Windows 10.0.18362.836 (1903/May2019Update/19H1)
Intel Core i3-4150 CPU 3.50GHz (Haswell), 1 CPU, 4 logical and 2 physical cores
.NET Core SDK=3.1.202
[Host] : .NET Core 3.1.4 (CoreCLR 4.700.20.20201, CoreFX 4.700.20.22101), X64 RyuJIT
DefaultJob : .NET Core 3.1.4 (CoreCLR 4.700.20.20201, CoreFX 4.700.20.22101), X64 RyuJIT
Method | Mean | Error | StdDev |
---|---|---|---|
HttpClient_GetAsync | 3.945 μs | 0.2050 μs | 0.5850 μs |
WebApiClientCore_GetAsync | 13.320 μs | 0.2604 μs | 0.3199 μs |
Refit_GetAsync | 43.503 μs | 0.8489 μs | 1.0426 μs |
Method | Mean | Error | StdDev |
---|---|---|---|
HttpClient_PostAsync | 4.876 μs | 0.0972 μs | 0.2092 μs |
WebApiClientCore_PostAsync | 14.018 μs | 0.1829 μs | 0.2246 μs |
Refit_PostAsync | 46.512 μs | 0.7885 μs | 0.7376 μs |
- 支持Task、Task<>和ITask<>三种异步返回
- 支持模型自动转换为Xml、Json、Form、和FormData共4种请求格式的内容
- 支持HttpResponseMessage、byte[]、string和Stream原生类型返回内容
- 支持原生HttpContent(比如StringContent)类型直接做为请求参数
- 内置丰富的能满足各种环境的常用特性(ActionAttribute和ParameterAttribute)
- 内置常用的FormDataFile等参数类型,同时支持自定义IApiParameter参数类型作为参数值
- 支持用户自定义IApiActionAttribute、IApiParameterAttribue、IApiReturnAttribute和IApiFilterAttribute
这个OpenApi文档在petstore.swagger.io,代码为使用WebApiClientCore.OpenApi.SourceGenerator工具将其OpenApi文档反向生成得到
namespace Petstore
{
/// <summary>
/// Everything about your Pets
/// </summary>
[LoggingFilter]
[HttpHost("https://petstore.swagger.io/v2/")]
public interface IPetApi : IHttpApi
{
/// <summary>
/// Add a new pet to the store
/// </summary>
/// <param name="body">Pet object that needs to be added to the store</param>
[HttpPost("pet")]
Task AddPetAsync([Required] [JsonContent] Pet body, CancellationToken token = default);
/// <summary>
/// Update an existing pet
/// </summary>
/// <param name="body">Pet object that needs to be added to the store</param>
[HttpPut("pet")]
Task<HttpResponseMessage> UpdatePetAsync([Required] [JsonContent] Pet body, CancellationToken token = default);
/// <summary>
/// Finds Pets by status
/// </summary>
/// <param name="status">Status values that need to be considered for filter</param>
/// <returns>successful operation</returns>
[HttpGet("pet/findByStatus")]
ITask<List<Pet>> FindPetsByStatusAsync([Required] IEnumerable<Anonymous> status);
/// <summary>
/// Finds Pets by tags
/// </summary>
/// <param name="tags">Tags to filter by</param>
/// <returns>successful operation</returns>
[Obsolete]
[HttpGet("pet/findByTags")]
ITask<List<Pet>> FindPetsByTagsAsync([Required] [PathQuery] IEnumerable<string> tags);
/// <summary>
/// Find pet by ID
/// </summary>
/// <param name="petId">ID of pet to return</param>
/// <returns>successful operation</returns>
[HttpGet("pet/{petId}")]
ITask<Pet> GetPetByIdAsync([Required] long petId);
/// <summary>
/// Updates a pet in the store with form data
/// </summary>
/// <param name="petId">ID of pet that needs to be updated</param>
/// <param name="name">Updated name of the pet</param>
/// <param name="status">Updated status of the pet</param>
[HttpPost("pet/{petId}")]
Task UpdatePetWithFormAsync([Required] long petId, [FormFiled] string name, [FormFiled] string status);
/// <summary>
/// Deletes a pet
/// </summary>
/// <param name="api_key"></param>
/// <param name="petId">Pet id to delete</param>
[HttpDelete("pet/{petId}")]
Task DeletePetAsync([Header("api_key")] string api_key, [Required] long petId);
/// <summary>
/// uploads an image
/// </summary>
/// <param name="petId">ID of pet to update</param>
/// <param name="additionalMetadata">Additional data to pass to server</param>
/// <param name="file">file to upload</param>
/// <returns>successful operation</returns>
[LoggingFilter(Enable = false)]
[HttpPost("pet/{petId}/uploadImage")]
ITask<ApiResponse> UploadFileAsync([Required] long petId, [FormDataText] string additionalMetadata, FormDataFile file);
}
}
这个接口是在WebApiClientCore.Extensions.OAuths.IOAuthClient.cs代码中声明
using System;
using System.ComponentModel.DataAnnotations;
using System.Diagnostics.CodeAnalysis;
using System.Threading.Tasks;
using WebApiClientCore.Attributes;
namespace WebApiClientCore.Extensions.OAuths
{
/// <summary>
/// 定义Token客户端的接口
/// </summary>
[LoggingFilter]
[XmlReturn(Enable = false)]
[JsonReturn(EnsureMatchAcceptContentType = false, EnsureSuccessStatusCode = false)]
public interface IOAuthClient
{
/// <summary>
/// 以client_credentials授权方式获取token
/// </summary>
/// <param name="endpoint">token请求地址</param>
/// <param name="credentials">身份信息</param>
/// <returns></returns>
[HttpPost]
[FormField("grant_type", "client_credentials")]
Task<TokenResult> RequestTokenAsync([Required, Uri] Uri endpoint, [Required, FormContent] ClientCredentials credentials);
/// <summary>
/// 以password授权方式获取token
/// </summary>
/// <param name="endpoint">token请求地址</param>
/// <param name="credentials">身份信息</param>
/// <returns></returns>
[HttpPost]
[FormField("grant_type", "password")]
Task<TokenResult> RequestTokenAsync([Required, Uri] Uri endpoint, [Required, FormContent] PasswordCredentials credentials);
/// <summary>
/// 刷新token
/// </summary>
/// <param name="endpoint">token请求地址</param>
/// <param name="credentials">身份信息</param>
/// <returns></returns>
[HttpPost]
[FormField("grant_type", "refresh_token")]
Task<TokenResult> RefreshTokenAsync([Required, Uri] Uri endpoint, [Required, FormContent] RefreshTokenCredentials credentials);
}
}
WebApiClientCore.Analyzers提供编码时语法分析与提示。
比如[Header]特性,可以声明在Interface、Method和Parameter三个地方,但是必须使用正确的构造器,否则运行时会抛出异常。有了语法分析功能,在声明接口时就不会使用不当的语法。如果想让语法分析生效,你的接口必须继承空方法的IHttpApi接口。
/// <summary>
/// 你的接口,记得要实现IHttpApi
/// </summary>
public interface IYourApi : IHttpApi
{
...
}
var services = new ServiceCollection();
services.AddHttpApi<IPetApi>(o =>
{
o.UseParameterPropertyValidate = true;
o.UseReturnValuePropertyValidate = false;
o.KeyValueSerializeOptions.IgnoreNullValues = true;
o.HttpHost = new Uri("http://localhost:6000/");
});
public class MyService
{
private readonly IpetApi petApi;
// 构造器注入IpetApi
public MyService(IpetApi petApi)
{
tihs.petApi = petApi;
}
}
每个接口的选项对应为HttpApiOptions<THttpApi>
,除了Action配置,我们也可以使用Configuration配置结合一起使用,这部分内容为Microsoft.Extensions.Options范畴。
services
.ConfigureHttpApi<IpetApi>(Configuration.GetSection(nameof(IpetApi)))
.ConfigureHttpApi<IpetApi>(o =>
{
// 符合国情的不标准时间格式,有些接口就是这么要求必须不标准
o.JsonSerializeOptions.Converters.Add(new JsonLocalDateTimeConverter("yyyy-MM-dd HH:mm:ss"));
});
{
"IpetApi": {
"HttpHost": "http://www.webappiclient.com/",
"UseParameterPropertyValidate": false,
"UseReturnValuePropertyValidate": false,
"JsonSerializeOptions": {
"IgnoreNullValues": true,
"WriteIndented": false
}
}
}
所有的Uri拼接都是通过Uri(Uri baseUri, Uri relativeUri)这个构造器生成。
http://a.com/
+b/c/d
=http://a.com/b/c/d
http://a.com/path1/
+b/c/d
=http://a.com/path1/b/c/d
http://a.com/path1/path2/
+b/c/d
=http://a.com/path1/path2/b/c/d
http://a.com
+b/c/d
=http://a.com/b/c/d
http://a.com/path1
+b/c/d
=http://a.com/b/c/d
http://a.com/path1/path2
+b/c/d
=http://a.com/path1/b/c/d
事实上http://a.com
与http://a.com/
是完全一样的,他们的path都是/
,所以才会表现一样。为了避免低级错误的出现,请使用的标准baseUri书写方式,即使用/
作为baseUri的结尾的第一种方式。
按照OpenApi,一个集合在Uri的Query或表单中支持5种表述方式,分别是:
- Csv // 逗号分隔
- Ssv // 空格分隔
- Tsv // 反斜杠分隔
- Pipes // 竖线分隔
- Multi // 多个同名键的键值对
对于 id = new string []{"001","002"} 这样的值,处理后分别是
- id=001,002
- id=001 002
- id=001\002
- id=001|002
- id=001&id=002
默认的,PathQuryAttribute与FormContentAttribute使用了Multi处理方式,可以设置其CollectionFormat属性为其它值,比如:[FormContent(CollectionFormat = CollectionFormat.Csv)]
这个用于控制客户端希望服务器返回什么样的内容格式,比如json或xml。
缺省配置是[JsonReturn(0.01),XmlReturn(0.01)],对应的请求accept值是
Accept: application/json; q=0.01, application/xml; q=0.01
在Interface或Method上显式地声明[JsonReturn]
,请求accept变为Accept: application/json, application/xml; q=0.01
在Interface或Method上声明[JsonReturn(Enable = false)]
,请求变为Accept: application/xml; q=0.01
在整个Interface或某个Method上声明[LoggingFilter]
,即可把请求和响应的内容输出到LoggingFactory中。如果要排除某个Method不打印日志,在该Method上声明[LoggingFilter(Enable = false)]
,即可将本Method排除。
[LoggingFilter]
public interface IUserApi : IHttpApi
{
[HttpGet("api/users/{account}")]
ITask<HttpResponseMessage> GetAsync([Required]string account);
// 禁用日志
[LoggingFilter(Enable =false)]
[HttpPost("api/users/body")]
Task<User> PostByJsonAsync([Required, JsonContent]User user, CancellationToken token = default);
}
class MyLogging : LoggingFilterAttribute
{
protected override Task WriteLogAsync(ApiResponseContext context, LogMessage logMessage)
{
xxlogger.Log(logMessage.ToIndentedString(spaceCount: 4));
return Task.CompletedTask;
}
}
使用ITask<>异步声明,就有Retry的扩展,Retry的条件可以为捕获到某种Exception或响应模型符合某种条件。
var result = await youApi.GetModelAsync(id: "id001")
.Retry(maxCount: 3)
.WhenCatch<HttpRequestException>()
.WhenResult(r => r.ErrorCode > 0);
请求一个接口,不管出现何种异常,最终都抛出HttpRequestException,HttpRequestException的内部异常为实际具体异常,之所以设计为内部异常,是为了完好的保存内部异常的堆栈信息。
WebApiClient内部的很多异常都基于ApiException这个抽象异常,也就是很多情况下,抛出的异常都是内为某个ApiException的HttpRequestException。
try
{
var model = await api.GetAsync();
}
catch (HttpRequestException ex) when (ex.InnerException is ApiInvalidConfigException configException)
{
// 请求配置异常
}
catch (HttpRequestException ex) when (ex.InnerException is ApiResponseStatusException statusException)
{
// 响应状态码异常
}
catch (HttpRequestException ex) when (ex.InnerException is ApiException apiException)
{
// 抽象的api异常
}
catch (HttpRequestException ex) when (ex.InnerException is SocketException socketException)
{
// socket连接层异常
}
catch (HttpRequestException ex)
{
// 请求异常
}
catch (Exception ex)
{
// 异常
}
配置CacheAttribute特性的Method会将本次的响应内容缓存起来,下一次如果符合预期条件的话,就不会再请求到远程服务器,而是从IResponseCacheProvider获取缓存内容,开发者可以自己实现ResponseCacheProvider。
// 缓存一分钟
[Cache(60 * 1000)]
[HttpGet("api/users/{account}")]
ITask<HttpResponseMessage> GetAsync([Required]string account);
public class RedisResponseCacheProvider : IResponseCacheProvider
{
public string Name => nameof(RedisResponseCacheProvider);
public Task<ResponseCacheResult> GetAsync(string key)
{
throw new NotImplementedException();
}
public Task SetAsync(string key, ResponseCacheEntry entry, TimeSpan expiration)
{
throw new NotImplementedException();
}
}
// 注册RedisResponseCacheProvider
var services = new ServiceCollection();
services.AddSingleton<IResponseCacheProvider, RedisResponseCacheProvider>();
有时候我们未必需要强模型,假设我们已经有原始的form文本内容,或原始的json文本内容,甚至是System.Net.Http.HttpContent对象,只需要把这些原始内请求到远程远程器。
[HttpPost]
Task PostAsync([RawStringContent("txt/plain")] string text);
[HttpPost]
Task PostAsync(StringContent text);
[HttpPost]
Task PostAsync([RawJsonContent] string json);
[HttpPost]
Task PostAsync([RawXmlContent] string xml);
[HttpPost]
Task PostAsync([RawFormContent] string form);
在某些极限情况下,比如人脸比对的接口,我们输入模型与传输模型未必是对等的:
{
"image1" : "图片1的base64",
"image2" : "图片2的base64"
}
class FaceModel
{
public Bitmap Image1 {get; set;}
public Bitmap Image2 {get; set;}
}
我们希望构造模型实例时传入Bitmap对象,但传输的时候变成Bitmap的base64值,所以我们要改造FaceModel,让它实现IApiParameter接口:
class FaceModel : IApiParameter
{
public Bitmap Image1 { get; set; }
public Bitmap Image2 { get; set; }
public Task OnRequestAsync(ApiParameterContext context)
{
var image1 = GetImageBase64(this.Image1);
var image2 = GetImageBase64(this.Image2);
var model = new { image1, image2 };
var options = context.HttpContext.Options.JsonSerializeOptions;
var json = System.Text.Json.JsonSerializer.Serialize(model, options);
context.HttpContext.RequestMessage.Content = new StringContent(json, Encoding.UTF8, "application/json");
return Task.CompletedTask;
}
private static string GetImageBase64(Bitmap image)
{
using var stream = new MemoryStream();
image.Save(stream, System.Drawing.Imaging.ImageFormat.Jpeg);
return Convert.ToBase64String(stream.ToArray());
}
}
最后,我们在使用改进后的FaceModel来请求
public interface IFaceApi
{
[HttpPost("/somePath")]
Task<HttpResponseMessage> PostAsync(FaceModel faces);
}
除了常见的xml或json响应内容要反序列化为强类型结果模型,你可能会遇到其它的二进制协议响应内容,比如google的ProtoBuf二进制内容。
public class ProtobufContentAttribute : HttpContentAttribute
{
public string ContentType { get; set; } = "application/x-protobuf";
protected override Task SetHttpContentAsync(ApiParameterContext context)
{
var stream = new MemoryStream();
if (context.ParameterValue != null)
{
Serializer.NonGeneric.Serialize(stream, context.ParameterValue);
stream.Position = 0L;
}
var content = new StreamContent(stream);
content.Headers.ContentType = new MediaTypeHeaderValue(this.ContentType);
context.HttpContext.RequestMessage.Content = content;
return Task.CompletedTask;
}
}
public class ProtobufReturnAttribute : ApiReturnAttribute
{
public ProtobufReturnAttribute(string acceptContentType = "application/x-protobuf")
: base(new MediaTypeWithQualityHeaderValue(acceptContentType))
{
}
public override async Task SetResultAsync(ApiResponseContext context)
{
if (context.ApiAction.Return.DataType.IsRawType == false)
{
var stream = await context.HttpContext.ResponseMessage.Content.ReadAsStreamAsync();
context.Result = Serializer.NonGeneric.Deserialize(context.ApiAction.Return.DataType.Type, stream);
}
}
}
[ProtobufReturn]
public interface IProtobufApi
{
[HttpPut("/users/{id}")]
Task<User> UpdateAsync([Required, PathQuery] string id, [ProtobufContent] User user);
}
在实际应用场景中,常常会遇到一些设计不标准的畸形接口,主要是早期还没有restful概念时期的接口,我们要区分分析这些接口,包装为好友的客户端调用接口。
例如服务器要求一个Query参数的名字为field-Name
,这个是c#关键字或变量命名不允许的,我们可以使用[AliasAsAttribute]
来达到这个要求:
[HttpGet("api/users/{account}")]
ITask<HttpResponseMessage> GetAsync([Required]string account, [AliasAs("field-Name")] string fieldName);
然后最终请求uri变为api/users/account1
?field-name=fileName1
字段 | 值 |
---|---|
field1 | abc |
field2 | {"name":"jName","data":{"data1":"jData1"}} |
对应强类型模型是
class Model
{
public string Filed1 {get; set;}
public string Field2 {get; set;}
}
我们在构建这个Model的实例时,不得不使用json序列化将field2的实例得到json文本,然后赋值给field2这个string属性,工作量大而且没有约束性。
依托于JsonString<>
这个类型,现在只要我们把Field2结构声明为强类型模型,然后包装为JsonString<>
类型,最后为HttpApiOptions添加JsonStringTypeConverter即可。
class Model
{
public string Filed1 {get; set;}
public JsonString<Field2Info> Field2 {get; set;}
}
class Field2Info
{
public string Name {get; set;}
public Field2Data data {get; set;}
}
class Field2Data
{
public string data1 {get; set;}
}
// 添加转换器
services
.AddHttpApi<IMyApi>(o =>
{
o.HttpHost = new Uri("http://localhost:6000/");
o.KeyValueSerializeOptions.Converters.Add(JsonStringTypeConverter.Default);
});
明明响应的内容肉眼看上是json内容,但服务响应头里没有ContentType告诉客户端这内容是json,这好比客户端使用Form或json提交时就不在请求头告诉服务器内容格式是什么,而是让服务器猜测一样的道理。
解决办法是在Interface或Method声明[JsonReturn]
特性,并设置其EnsureMatchAcceptContentType属性为false,表示ContentType不是期望值匹配也要处理。
[JsonReturn(EnsureMatchAcceptContentType = false)]
public interface IJsonResponseApi : IHttpApi
{
}
例如每个请求的url额外的动态添加一个叫sign的参数,这个sign可能和请求参数值有关联,每次都需要计算。
我们可以自定义ApiFilterAttribute来实现自己的sign功能,然后把自定义Filter声明到Interface或Method即可
class SignFilterAttribute : ApiFilterAttribute
{
public override Task OnRequestAsync(ApiRequestContext context)
{
var sign = DateTime.Now.Ticks.ToString();
context.HttpContext.RequestMessage.AddUrlQuery("sign", sign);
return Task.CompletedTask;
}
}
[SignFilter]
public interface ISignedApi
{
...
}
services
.AddHttpApi<IMyApi>(o =>
{
o.HttpHost = new Uri("http://localhost:6000/");
})
.ConfigurePrimaryHttpMessageHandler(() => new HttpClientHandler
{
UseProxy = true,
Proxy = new WebProxy
{
Address = new Uri("http://proxy.com"),
Credentials = new NetworkCredential
{
UserName = "useranme",
Password = "pasword"
}
}
});
有些服务器为了限制客户端的连接,开启了https双向验证,只允许它执有它颁发的证书的客户端进行连接
services
.AddHttpApi<IMyApi>(o =>
{
o.HttpHost = new Uri("http://localhost:6000/");
})
.ConfigurePrimaryHttpMessageHandler(() =>
{
var handler = new HttpClientHandler();
handler.ClientCertificates.Add(yourCert);
return handler;
});
如果请求的接口不幸使用了Cookie保存身份信息机制,那么就要考虑维持CookieContainer实例不要跟随HttpMessageHandler的生命周期,默认的HttpMessageHandler最短只有2分钟的生命周期。
var cookieContainer = new CookieContainer();
services
.AddHttpApi<IMyApi>(o =>
{
o.HttpHost = new Uri("http://localhost:6000/");
})
.ConfigurePrimaryHttpMessageHandler(() =>
{
var handler = new HttpClientHandler();
handler.CookieContainer = cookieContainer;
return handler;
});
使用WebApiClientCore.Extensions.OAuths扩展,轻松支持token的获取、刷新与应用
// 为接口注册与配置token提者选项
services.AddClientCredentialsTokenProvider<IMyApi>(o =>
{
o.Endpoint = new Uri("http://localhost:6000/api/tokens");
o.Credentials.Client_id = "clientId";
o.Credentials.Client_secret = "xxyyzz";
});
/// <summary>
/// 用户操作接口
/// </summary>
[ClientCredentialsToken]
public interface IMyApi
{
...
}
清空Token,未过期的token也强制刷新
var providers = serviceProvider.GetServices<ITokenProvider>();
foreach(var item in providers)
{
// 强制清除token以支持下次获取到新的token
item.ClearToken();
}
自定义Token应用,得到token值,怎么用自己说了算
class MyTokenAttribute : ClientCredentialsTokenAttribute
{
protected override void UseTokenResult(ApiRequestContext context, TokenResult tokenResult)
{
context.HttpContext.RequestMessage.Headers.TryAddWithoutValidation("xxx-header", tokenResult.Access_token);
}
}
/// <summary>
/// 用户操作接口
/// </summary>
[MyToken]
public interface IMyApi
{
...
}
Microsoft.Extensions.Http支持收入各种第三方的HttpMessageHandler来build出一种安全的HttpClient,同时支持将此HttpClient实例包装为强类型服务的目标服务类型注册功能。
Microsoft.Extensions.Http.Polly项目依托于Polly,将Polly策略实现到System.Net.Http.DelegatingHandler,其handler可以为HttpClient提供重试、降级和断路等功能。
WebApiClientCore可以将Microsoft.Extensions.Http创建出来的HttpClient实例包装为声明式接口的代理实例,使开发者从面向命令式的编程模式直达声明式的AOP编程。