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在.Net Core 2.2中以IActionResult形式返回HttpResponseMessage的正确方法

  •  1
  • LP13  · 技术社区  · 6 年前

      [Route("api/v1")]
      public class RoutesController : Controller
      {
          [HttpPost]
          [Route("routes")]
          public async Task<IActionResult> Routes([FromBody]JObject request)
          {
                     
            var httpClient = new HttpClient();
    
            // here based on request httpCLient will make `POST` or `GET` or `PUT` request
            // and returns `Task<HttpResponseMessage>`. Lets assume its making `GET` 
            // call
    
           Task<HttpResponseMessage> response = await
             httpClient.GetAsync(request["resource"]);
                
           /*  ??? what is the correct way to return response as `IActionResult`*/
          }        
      }
    

    基于 SO

            return StatusCode((int)response.StatusCode, response);
    

    不过,我不确定是否发送 HttpResponseMessage ObjectResult 这是正确的方法。

    我还想确保内容协商能够奏效。

    3 回复  |  直到 4 年前
        1
  •  28
  •   LP13    6 年前
    public class HttpResponseMessageResult : IActionResult
    {
        private readonly HttpResponseMessage _responseMessage;
    
        public HttpResponseMessageResult(HttpResponseMessage responseMessage)
        {
            _responseMessage = responseMessage; // could add throw if null
        }
    
        public async Task ExecuteResultAsync(ActionContext context)
        {
            var response = context.HttpContext.Response;
    
    
            if (_responseMessage == null)
            {
                var message = "Response message cannot be null";
    
                throw new InvalidOperationException(message);
            }
    
            using (_responseMessage)
            {
                response.StatusCode = (int)_responseMessage.StatusCode;
    
                var responseFeature = context.HttpContext.Features.Get<IHttpResponseFeature>();
                if (responseFeature != null)
                {
                    responseFeature.ReasonPhrase = _responseMessage.ReasonPhrase;
                }
    
                var responseHeaders = _responseMessage.Headers;
    
                // Ignore the Transfer-Encoding header if it is just "chunked".
                // We let the host decide about whether the response should be chunked or not.
                if (responseHeaders.TransferEncodingChunked == true &&
                    responseHeaders.TransferEncoding.Count == 1)
                {
                    responseHeaders.TransferEncoding.Clear();
                }
    
                foreach (var header in responseHeaders)
                {
                    response.Headers.Append(header.Key, header.Value.ToArray());
                }
    
                if (_responseMessage.Content != null)
                {
                    var contentHeaders = _responseMessage.Content.Headers;
    
                    // Copy the response content headers only after ensuring they are complete.
                    // We ask for Content-Length first because HttpContent lazily computes this
                    // and only afterwards writes the value into the content headers.
                    var unused = contentHeaders.ContentLength;
    
                    foreach (var header in contentHeaders)
                    {
                        response.Headers.Append(header.Key, header.Value.ToArray());
                    }
    
                    await _responseMessage.Content.CopyToAsync(response.Body);
                }
            }
        }
    
        2
  •  25
  •   Kalten    4 年前

    您可以创建一个自定义IActionResult,它将封装传输逻辑。

    public async Task<IActionResult> Routes([FromBody]JObject request)
    {
        var httpClient = new HttpClient();
    
        HttpResponseMessage response = await httpClient.GetAsync("");
    
        // Here we ask the framework to dispose the response object a the end of the user resquest
        this.HttpContext.Response.RegisterForDispose(response);
    
        return new HttpResponseMessageResult(response);
    }
    
    public class HttpResponseMessageResult : IActionResult
    {
        private readonly HttpResponseMessage _responseMessage;
    
        public HttpResponseMessageResult(HttpResponseMessage responseMessage)
        {
            _responseMessage = responseMessage; // could add throw if null
        }
    
        public async Task ExecuteResultAsync(ActionContext context)
        {
            context.HttpContext.Response.StatusCode = (int)_responseMessage.StatusCode;
    
            foreach (var header in _responseMessage.Headers)
            {
                context.HttpContext.Response.Headers.TryAdd(header.Key, new StringValues(header.Value.ToArray()));
            }
    
            using (var stream = await _responseMessage.Content.ReadAsStreamAsync())
            {
                await stream.CopyToAsync(context.HttpContext.Response.Body);
                await context.HttpContext.Response.Body.FlushAsync();
            }
        }
    }
    
        3
  •  0
  •   Richard Fuller    6 年前

    ASP.NET核心具有返回对象 RedirectResult

        4
  •  -1
  •   Michael G    4 年前

    只需将响应包装在Ok()操作返回类型中:

    return Ok(response) 
    

    因此,您的代码看起来像:

    [Route("api/v1")]
    public class RoutesController : Controller
    {
        [HttpPost]
        [Route("routes")]
        public async Task<IActionResult> Routes([FromBody]JObject request)
        {
    
          var httpClient = new HttpClient();
       
          Task<HttpResponseMessage> response = await httpClient.GetAsync(request["resource"]);
    
          return Ok(response);
        }        
    }
    

       Task<HttpResponseMessage> response = await httpClient.GetAsync(request["resource"]);
    

       HttpResponseMessage response = await httpClient.GetAsync(request["resource"]);
    

    等候 关键字返回任务。

    更多信息请点击此处: https://docs.microsoft.com/en-us/aspnet/core/web-api/action-return-types?view=aspnetcore-3.1