我有一个HttpClient,我正在使用一个REST API。但是,我在设置授权标头时遇到了麻烦。我需要将标头设置为我从执行OAuth请求中接收到的令牌。 我看到了一些。net的代码,建议如下:
httpClient.DefaultRequestHeaders.Authorization = new Credential(OAuth.token);
然而,凭据类在WinRT中不存在。有人知道如何设置授权头吗?
我有一个HttpClient,我正在使用一个REST API。但是,我在设置授权标头时遇到了麻烦。我需要将标头设置为我从执行OAuth请求中接收到的令牌。 我看到了一些。net的代码,建议如下:
httpClient.DefaultRequestHeaders.Authorization = new Credential(OAuth.token);
然而,凭据类在WinRT中不存在。有人知道如何设置授权头吗?
当前回答
BaseWebApi.cs
public abstract class BaseWebApi
{
//Inject HttpClient from Ninject
private readonly HttpClient _httpClient;
public BaseWebApi(HttpClient httpclient)
{
_httpClient = httpClient;
}
public async Task<TOut> PostAsync<TOut>(string method, object param, Dictionary<string, string> headers, HttpMethod httpMethod)
{
//Set url
HttpResponseMessage response;
using (var request = new HttpRequestMessage(httpMethod, url))
{
AddBody(param, request);
AddHeaders(request, headers);
response = await _httpClient.SendAsync(request, cancellationToken);
}
if(response.IsSuccessStatusCode)
{
return await response.Content.ReadAsAsync<TOut>();
}
//Exception handling
}
private void AddHeaders(HttpRequestMessage request, Dictionary<string, string> headers)
{
request.Headers.Accept.Clear();
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
if (headers == null) return;
foreach (var header in headers)
{
request.Headers.Add(header.Key, header.Value);
}
}
private static void AddBody(object param, HttpRequestMessage request)
{
if (param != null)
{
var content = JsonConvert.SerializeObject(param);
request.Content = new StringContent(content);
request.Content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
}
}
SubWebApi.cs
public sealed class SubWebApi : BaseWebApi
{
public SubWebApi(HttpClient httpClient) : base(httpClient) {}
public async Task<StuffResponse> GetStuffAsync(int cvr)
{
var method = "get/stuff";
var request = new StuffRequest
{
query = "GiveMeStuff"
}
return await PostAsync<StuffResponse>(method, request, GetHeaders(), HttpMethod.Post);
}
private Dictionary<string, string> GetHeaders()
{
var headers = new Dictionary<string, string>();
var basicAuth = GetBasicAuth();
headers.Add("Authorization", basicAuth);
return headers;
}
private string GetBasicAuth()
{
var byteArray = Encoding.ASCII.GetBytes($"{SystemSettings.Username}:{SystemSettings.Password}");
var authString = Convert.ToBase64String(byteArray);
return $"Basic {authString}";
}
}
其他回答
我偶然发现了这条旧线索。我遇到的问题是我知道使用静态HttpClient,但是我的令牌需要每59分钟刷新一次。
所以我可以使用HttpClientFactory,但是因为我的一个项目仍然在. net 4.8中,我创建了一个从HttpClient继承的类,所以我在所有项目中都有类似的代码。需要一个秘密才能获得令牌(我使用identityserver4)。
然后我将它设置为DI中的单例(我在这里使用Ninject):
Bind<MyHttpClient>().ToMethod(c =>
{
var accessKey = ConfigurationManager.AppSettings["AccessKey"];
var client = new MyHttpClient(accessKey)
{
BaseAddress = new Uri(MyUrls.MyApiBaseUrl)
};
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
return client;
}).InSingletonScope();
然后是类本身——以它用来访问的API命名:
public class MyHttpClient : BaseHttpClient
{
private static readonly HttpClient _authHttpClient = new HttpClient();
private string _secret;
public MyHttpClient(string secret)
{
_secret = secret;
}
/// <summary>
/// Add the token to each and every request, cached for 1 minute less than the token's lifetime
/// </summary>
/// <param name="request"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
public override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
cancellationToken.ThrowIfCancellationRequested();
var cacheSeconds = 3600 - 60; // Default of 59 minutes
var token = CacheHelper<string>.Get("MyToken", cacheSeconds * 60, () =>
{
var authorityUrl = MyUrls.AuthServerUrl;
// discover endpoints from metadata
DiscoveryDocumentResponse disco;
disco = _authHttpClient.GetDiscoveryDocumentAsync(authorityUrl).Result;
if (disco.IsError)
{
throw new Exception("Error getting discovery document: " + disco.Error);
}
// request token
var tokenResponse = _authHttpClient.RequestClientCredentialsTokenAsync(new ClientCredentialsTokenRequest
{
Address = disco.TokenEndpoint,
ClientId = "myapp",
ClientSecret = _secret,
Scope = "myapi"
}).Result;
if (tokenResponse.IsError)
{
throw new Exception("Error getting token: " + tokenResponse.Error);
}
if (tokenResponse.ExpiresIn < cacheSeconds + 60)
{
throw new Exception($"Token expires in {tokenResponse.ExpiresIn}s, which is less than {cacheSeconds + 60}");
}
if (tokenResponse.ExpiresIn > cacheSeconds + 60)
{
Log.Warn().Message($"Token expiry in {tokenResponse.ExpiresIn}s, which is greater than {cacheSeconds}").Write();
}
return tokenResponse.AccessToken;
});
// THIS IS THE BIT - Assign this inside a SendAsync override and you are done!
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
return base.SendAsync(request, cancellationToken);
}
}
最后为了完整起见,我的CacheHelper类看起来是这样的:
public static class CacheHelper<T>
{
private static readonly object _locker = new object();
public static T Get(string cacheName, int cacheTimeoutSeconds, Func<T> func)
{
var obj = MemoryCache.Default.Get(cacheName, null);
if (obj != null) return (T)obj;
lock (_locker)
{
obj = MemoryCache.Default.Get(cacheName, null);
if (obj == null)
{
obj = func();
var cip = new CacheItemPolicy
{
AbsoluteExpiration = new DateTimeOffset(DateTime.UtcNow.AddSeconds(cacheTimeoutSeconds))
};
MemoryCache.Default.Set(cacheName, obj, cip);
}
}
return (T)obj;
}
}
如果你想重用HttpClient,建议不要使用DefaultRequestHeaders,因为它们是用来发送每个请求的。
你可以试试这个:
var requestMessage = new HttpRequestMessage
{
Method = HttpMethod.Post,
Content = new StringContent("...", Encoding.UTF8, "application/json"),
RequestUri = new Uri("...")
};
requestMessage.Headers.Authorization = new AuthenticationHeaderValue("Basic",
Convert.ToBase64String(System.Text.ASCIIEncoding.ASCII.GetBytes($"{user}:{password}")));
var response = await _httpClient.SendAsync(requestMessage);
这可以工作,如果你从服务接收到一个json或xml,我认为这可以给你一个关于标题和T类型如何工作的想法,如果你使用函数MakeXmlRequest(把结果放在xmldocumentnet)和MakeJsonRequest(把json放在类你希望有相同的结构,json响应)在下一种方式
/*-------------------------example of use-------------*/
MakeXmlRequest<XmlDocument>("your_uri",result=>your_xmlDocument_variable = result,error=>your_exception_Var = error);
MakeJsonRequest<classwhateveryouwant>("your_uri",result=>your_classwhateveryouwant_variable=result,error=>your_exception_Var=error)
/*-------------------------------------------------------------------------------*/
public class RestService
{
public void MakeXmlRequest<T>(string uri, Action<XmlDocument> successAction, Action<Exception> errorAction)
{
XmlDocument XMLResponse = new XmlDocument();
string wufooAPIKey = ""; /*or username as well*/
string password = "";
StringBuilder url = new StringBuilder();
url.Append(uri);
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url.ToString());
string authInfo = wufooAPIKey + ":" + password;
authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
request.Timeout = 30000;
request.KeepAlive = false;
request.Headers["Authorization"] = "Basic " + authInfo;
string documento = "";
MakeRequest(request,response=> documento = response,
(error) =>
{
if (errorAction != null)
{
errorAction(error);
}
}
);
XMLResponse.LoadXml(documento);
successAction(XMLResponse);
}
public void MakeJsonRequest<T>(string uri, Action<T> successAction, Action<Exception> errorAction)
{
string wufooAPIKey = "";
string password = "";
StringBuilder url = new StringBuilder();
url.Append(uri);
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url.ToString());
string authInfo = wufooAPIKey + ":" + password;
authInfo = Convert.ToBase64String(Encoding.Default.GetBytes(authInfo));
request.Timeout = 30000;
request.KeepAlive = false;
request.Headers["Authorization"] = "Basic " + authInfo;
// request.Accept = "application/json";
// request.Method = "GET";
MakeRequest(
request,
(response) =>
{
if (successAction != null)
{
T toReturn;
try
{
toReturn = Deserialize<T>(response);
}
catch (Exception ex)
{
errorAction(ex);
return;
}
successAction(toReturn);
}
},
(error) =>
{
if (errorAction != null)
{
errorAction(error);
}
}
);
}
private void MakeRequest(HttpWebRequest request, Action<string> successAction, Action<Exception> errorAction)
{
try{
using (var webResponse = (HttpWebResponse)request.GetResponse())
{
using (var reader = new StreamReader(webResponse.GetResponseStream()))
{
var objText = reader.ReadToEnd();
successAction(objText);
}
}
}catch(HttpException ex){
errorAction(ex);
}
}
private T Deserialize<T>(string responseBody)
{
try
{
var toReturns = JsonConvert.DeserializeObject<T>(responseBody);
return toReturns;
}
catch (Exception ex)
{
string errores;
errores = ex.Message;
}
var toReturn = JsonConvert.DeserializeObject<T>(responseBody);
return toReturn;
}
}
}
对于现在(2021年)找到这个旧线程的人,请看看这个关于HttpClientFactory的文档,它是可注入的,也会在每个请求上重新运行,避免过期的令牌,这将使它对承载令牌,生成的客户端,池等有用。
TL;DR:使用HttpClientFactory和一个DelegatingHandler,它将作为与您配置的客户端的所有外发请求的中间件。
这就是我如何为Azure身份添加我的承载者(由Azure管理),但你当然可以获得你想要的令牌;
using Microsoft.Azure.Services.AppAuthentication;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
public class BearerTokenHandler : DelegatingHandler
{
public BearerTokenHandler(AzureServiceTokenProvider tokenProvider, string resource)
{
TokenProvider = tokenProvider;
Resource = resource;
}
public AzureServiceTokenProvider TokenProvider { get; }
public string Resource { get; }
protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
{
if (!request.Headers.Contains("Authorization"))
{
// Fetch your token here
string token = await TokenProvider.GetAccessTokenAsync(Resource);
request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", token);
}
return await base.SendAsync(request, cancellationToken);
}
}
我在Startup中这样配置我的类型化客户端(用NSwag生成);
var accessTokenProvider = new AzureServiceTokenProvider("<your-connection-string-for-access-token-provider>");
builder.Services.AddHttpClient<IOrdersClient, OrdersClient>().ConfigureHttpClient(async conf =>
{
conf.BaseAddress = new Uri("<your-api-base-url>");
}).AddHttpMessageHandler(() => new BearerTokenHandler(accessTokenProvider, "https://your-azure-tenant.onmicrosoft.com/api"));
然后你可以在任何你喜欢的地方注入你的IOrdersClient,所有的请求都会有承载者。
使用基本授权和Json参数。
using (HttpClient client = new HttpClient())
{
var request_json = "your json string";
var content = new StringContent(request_json, Encoding.UTF8, "application/json");
var authenticationBytes = Encoding.ASCII.GetBytes("YourUsername:YourPassword");
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",
Convert.ToBase64String(authenticationBytes));
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var result = await client.PostAsync("YourURL", content);
var result_string = await result.Content.ReadAsStringAsync();
}