I have a web api controller action that sends a request to another server and gets an image.
public class MyController : ApiController
{
public async Runner<HttpResponseMessage> Wms()
{
return await Run();
}
private Task<HttpResponseMessage> Run()
{
HttpRequestMessage requestMessage = new HttpRequestMessage();
requestMessage.RequestUri = "http://....";
foreach (var header in this.Request.Headers)
requestMessage.Headers.Add(header.Key, header.Value);
return requestMessage.SendAsync();
}
}
How can I get async request result of requestMessage.SendAsync()
You'll need to add the async modifier to the method and await SendAsync():
private async Task<HttpResponseMessage> RunAsync()
{
HttpRequestMessage requestMessage = new HttpRequestMessage();
requestMessage.RequestUri = "http://....";
foreach (var header in this.Request.Headers)
requestMessage.Headers.Add(header.Key, header.Value);
HttpResponseMessage response = await requestMessage.SendAsync();
string resultData = await response.Content.ReadAsStringAsync();
}
Or if you want the response inside Wms, you can await that.
Related
I have below code which use httpclient and use sendasync, when I test, it always run twice on API.
Controller :
[HttpGet("GetAllStores")]
public async Task<bookstores> GetAllStores()
{
Console.writeline("Trigger Stores")
return await dbContext.set<bookstores>().toListAsync()
}
httpclient
public async Task<IEnumerable<bookstores>> FetchAllStores()
{
var requestContent = new HttpRequestMessage
{
Method = HttpMethod.Get
};
var response = await httpClient.SendAsync("http://127.0.0.1:5000/GetAllStores", HttpCompletionOption.ResponseHeadersRead);
response.EnsureSuccessStatusCode();
return JsonSerializer.Deserialize<bookstores>(await response.Content.ReadAsStringAsync(), defaultJsonSerializerOptions);
}
Test
public async Task GetSettingProfile_AsExpected()
{
var sut = new ApiClient(
new HttpClient() { BaseAddress=new Uri("http://localhost:40331") });
await sut.FetchAllStores();
}
The output in console is show Trigger Stores two times
Can I know how to make it which call API in one time ?
I have a simple API gateway controller which returns an IActionResult. The issue is I am not able to read the body of the response.
If I comment out the using block in ExecuteResultAsync it seems to work fine but there is not content/body.
Not sure how to get this working with the httpbody being returned. RouteRequest returning HttpResponseMessage is not an option as it puts the response from the microservice as the body of the response from the Gateway.
So I need to use the HttpResponseMessageResult middleware, which works as expected for headers but not for the body.
public async Task<IActionResult> RouteRequest()
{
// Calls a method which send a request and gets a response and constructs a HttpResponseMessage
_contextAccessor.HttpContext.Response.RegisterForDispose(response);
return new HttpResponseMessageResult(response);
}
public class HttpResponseMessageResult : IActionResult
{
private readonly HttpResponseMessage _responseMessage;
public HttpResponseMessageResult(HttpResponseMessage responseMessage)
{
_responseMessage = responseMessage;
}
public async Task ExecuteResultAsync(ActionContext context)
{
context.HttpContext.Response.StatusCode = (int)_responseMessage.StatusCode;
var responseMessageHeadersArray = _responseMessage.Headers.ToArray();
for (int i = 0; i < responseMessageHeadersArray.Length; i++)
{
var header = responseMessageHeadersArray[i];
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();
}
}
}
Try this out, based on this good answer to a similar question, I used the ObjectResult class instead of manually manipulating the streams. When I run it with response from one of our API's (JSON), I get the same amount of data in the body of objectResult when it calls ExecuteAsync as were in the initial response.
public class HttpResponseMessageResult : IActionResult
{
private readonly HttpResponseMessage _responseMessage;
public HttpResponseMessageResult(HttpResponseMessage responseMessage)
{
_responseMessage = responseMessage;
}
public async Task ExecuteResultAsync(ActionContext context)
{
var objectResult = new ObjectResult(await _responseMessage.Content.ReadAsStreamAsync())
{StatusCode = (int)_responseMessage.StatusCode};
foreach (KeyValuePair<string, IEnumerable<string>> h in _responseMessage.Headers)
{
context.HttpContext.Response.Headers.TryAdd(h.Key, string.Join("", h.Value));
}
await objectResult.ExecuteResultAsync(context);
}
}
I need to build an html document and return it in my web api. All available answers on the net and the forum suggest using HttpResponseMessage. I would like to achieve this by IHttpActionResult. Below is what I have thus far:
[ResponseType(typeof(HttpResponseMessage))]
public async Task<IHttpActionResult> GetNotesViewModels()
{
var note = await GetHtmlText();
var response = new HttpResponseMessage();
response.Content = new StringContent(note);
response.Content.Headers.ContentType = new MediaTypeHeaderValue("text/html");
return Ok(ResponseMessage(response));
}
I am not receiving what I would like. What is missing here?
You could implement your own HtmlResult, like following (free-handed):
public class HtmlActionResult : IHttpActionResult
{
public HtmlActionResult (HttpRequestMessage request, string content)
{
Request = request;
Content= content;
}
public string Content { get; private set; }
public HttpRequestMessage Request { get; private set; }
public Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
{
return Task.FromResult(ExecuteResult());
}
public HttpResponseMessage ExecuteResult()
{
var response = new HttpResponseMessage();
if (!string.IsNullOrWhiteSpace(Content))
response.Content = new StringContent(Content, Encoding.UTF8, "text/html");
response.RequestMessage = Request;
return response;
}
}
And use it like this:
public async Task<IHttpActionResult> GetNotesViewModels()
{
var note = await GetHtmlText();
return new HtmlActionResult(Request, note);
}
I am trying to use the HttpClient class to call a POST method from my API which is supposed to add Server information to a DB.
The way I'm trying to call it is below. But when I step through it to debug it steps through my if statement for response.IsSuccessStatusCode.
public static async Task<Server> PostServer(Server server)
{
using (var client = new HttpClient())
{
client.BaseAddress = new Uri("http://localhost:50489/");
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
StringContent content = new StringContent(JsonConvert.SerializeObject(server));
// HTTP POST
HttpResponseMessage response = await client.PostAsync("api/Server/", content);
if (response.IsSuccessStatusCode)
{
string data = await response.Content.ReadAsStringAsync();
server = JsonConvert.DeserializeObject<Server>(data);
}
}
return server;
}
Also here is the POST method in my API below it was automatically generated in VS.
// POST: api/Servers
[ResponseType(typeof(Server))]
public async Task<IHttpActionResult> PostServer(Server server)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
db.Servers.Add(server);
await db.SaveChangesAsync();
return CreatedAtRoute("DefaultApi", new { id = server.Server_ID }, server);
}
The aim is to make controller that uses async method in my custom service.
Controller:
[Route("api/data/summary")]
[HttpGet]
public async Task<IHttpActionResult> Get()
{
var result = await DataService.GetDataObjects();
return Ok(result);
}
Service:
public static async Task<IEnumerable<DataObject>> GetDataObjects()
{
var apiKey = "some-api-key";
var path = "path-to-external-service";
using (var client = new HttpClient())
{
var dataToProcess = // some data object
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);
client.BaseAddress = new Uri(path);
HttpResponseMessage response = await client.PostAsJsonAsync("", dataToProcess);
var content = await response.Content.ReadAsStringAsync();
var result = MakeEntities(content); // some logic
return result;
}
}
But I came across with the problem that controller's action returns empty result before service actually finished processing data.
Could you please advice how to implement it correctly?
Your code is OK and controller doesn't seem to return a value before GetDataObjects returns value.
Except for the situations below:
MakeEntities uses some asynchronous operation and you don't await it inside MakeEntities. So MakeEntities return task.
Exception rises while your code is running. Make sure GetDataObjects and MakeEntities code works fine.
The aim is to make controller that uses async method in my custom service.
Controller:
[HttpGet]
[Route("api/data/summary")]
public async Task<IHttpActionResult> Get()
{
var result = await DataService.GetDataObjects().ConfigureAwait(false);
return Ok(result);
}
Service:
public static async Task<ResponseEntity> GetDataObjects()
{
ResponseEntity response = new ResponseEntity();
var apiKey = "some-api-key";
var path = "path-to-external-service";
using (var client = new HttpClient())
{
var dataToProcess = // some data object
client.BaseAddress = new Uri(path);
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", apiKey);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage response = await client.PostAsJsonAsync("", dataToProcess).ConfigureAwait(false);
string responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
var result = JsonConvert.DeserializeObject<ResponseEntity>(responseString);
return response;
}
}