How to call a endpoint in .Net core with request object

Question

I've a endpoint like below in Api 1

[HttpPost]
public ActionResult PostSchoolQuery([FromBody] SchoolQueryModel schoolQueryModel, [FromHeader] string authorization)
{

}

Here the Request Model class like below

public class SchoolQueryModel
{
 public List<Guid?> SchoolIds { get; set; }
 public List<Guid?> DistrictIds { get; set; }
}

And when I try to call the endpoint PostSchoolQuery from Api 2 like below , In api-1 I'm always receiving null values

 public ActionResult GetUserSchools(SchoolQueryModel getSchoolsModel)
        {
           dynamic schoolDetails = null;          
            var requestContent = new JsonSerializer.Serialize(getSchoolsModel);
            using (var client = new HttpClient())
            {
                client.DefaultRequestHeaders.Add("Authorization", _infrastructureAuthKey);
                var responseTask = client.PostAsync("http://localhost:6200/api/post_school_query", requestContent);
                if (responseTask.Result.IsSuccessStatusCode)
                {
                    var readTask = responseTask.Result.Content.ReadAsAsync<JObject>();
                    readTask.Wait();
                    schoolDetails = readTask.Result;
                }
            }
  }

let me know for a fix, Thanks

Does this answer your question? [Can't find how to use HttpContent](https://stackoverflow.com/questions/11145053/cant-find-how-to-use-httpcontent) — Vadim Martynov, Mar 03 '23 at 12:32
You really should be using `async`/`await` instead of waiting on tasks, that's a deadlock waiting to happen. — Etienne de Martel, Mar 06 '23 at 03:05

score 1 · Answer 1 · answered Mar 05 '23 at 09:52

First try to set the Content-Type header to "application/json" when making the request from Api 2:

client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

Then you need to create a StringContent object from the serialized request body, and pass it as the second argument to the PostAsync method. You can do this as follows:

var content = new StringContent(requestContent, Encoding.UTF8, "application/json");
var responseTask = client.PostAsync("http://localhost:6200/api/post_school_query", content);

So your GetUserSchools method should look like:

public ActionResult GetUserSchools(SchoolQueryModel getSchoolsModel)
{
   dynamic schoolDetails = null;          
    var requestContent = new JsonSerializer.Serialize(getSchoolsModel);
    using (var client = new HttpClient())
    {
        client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
        client.DefaultRequestHeaders.Add("Authorization", _infrastructureAuthKey);
        var content = new StringContent(requestContent, Encoding.UTF8, "application/json");
        var responseTask = client.PostAsync("http://localhost:6200/api/post_school_query", content);
        if (responseTask.Result.IsSuccessStatusCode)
        {
            var readTask = responseTask.Result.Content.ReadAsAsync<JObject>();
            readTask.Wait();
            schoolDetails = readTask.Result;
        }
    }
}

score 0 · Answer 2 · answered Mar 03 '23 at 12:28

Try this one PostAsJsonAsync

public ActionResult GetUserSchools(SchoolQueryModel getSchoolsModel)
{
    dynamic schoolDetails = null;

    using (var client = new HttpClient())
    {
        client.DefaultRequestHeaders.Add("Authorization", _infrastructureAuthKey);
        var responseTask = client.PostAsJsonAsync("http://localhost:6200/api/post_school_query", getSchoolsModel);
        if (responseTask.Result.IsSuccessStatusCode)
        {
            var readTask = responseTask.Result.Content.ReadAsAsync<JObject>();
            readTask.Wait();
            schoolDetails = readTask.Result;
        }
    }
}

Yes tried but still I received as null values – Vasanth R Mar 03 '23 at 12:36 — Vasanth R, Mar 03 '23 at 12:36

MutedExclamation · Answer 3 · 2023-03-03T13:19:04.063

This one works for me. I've also included some better practices:

Utilize async/await functionality. You shouldn't use .Result directly.
You should not create a HttpClient per request.

using System.Text;
using System.Text.Json;
using Microsoft.AspNetCore.Mvc;

namespace AspNetPlayground.Controllers;

[ApiController]
[Route("[controller]/[action]")]
public class TestController : ControllerBase
{
    private readonly HttpClient _httpClient;

    public TestController(IHttpClientFactory httpClientFactory) => _httpClient = httpClientFactory.CreateClient();

    [HttpPost]
    public Task<bool> IsNotNull([FromBody] SchoolQueryModel? schoolQueryModel) => Task.FromResult(schoolQueryModel is not null);

    [HttpPost]
    public async Task<bool> Run()
    {
        var getSchoolsModel = new SchoolQueryModel {SchoolIds = new() {Guid.NewGuid()}, DistrictIds = new() {Guid.NewGuid()}};
        using var requestContent = new StringContent(JsonSerializer.Serialize(getSchoolsModel), Encoding.UTF8, "application/json");
        using var response = await _httpClient.PostAsync("https://localhost:7041/Test/IsNotNull", requestContent);
        return response.IsSuccessStatusCode && await response.Content.ReadFromJsonAsync<bool>();
    }
}

public class SchoolQueryModel
{
    public List<Guid?> SchoolIds { get; init; } = new();
    public List<Guid?> DistrictIds { get; init; } = new();
}

actually my problem is different , even if i used async & await and the above best practice .. i'm receiving null values only in target endpoint — Vasanth R, Mar 03 '23 at 13:30
Please try the solution I posted. It does work for me. I suspect that your solution has some other issue, with authorization for example. — MutedExclamation, Mar 03 '23 at 13:43
here i'm getting Unable to resolve service for type 'System.Net.Http.IHttpClientFactory — Vasanth R, Mar 03 '23 at 16:51
In your startup code you have to call `AddHttpClient()` from the `Microsoft.Extensions.DependencyInjection` package. — MutedExclamation, Mar 17 '23 at 08:24

score 0 · Accepted Answer · answered Mar 05 '23 at 09:45

This fix works for me , I'm not sure why. if anyone knows please comment here

In my api -2 I used JObject instead of a request model and PostAsJsonAsync directly

public ActionResult GetUserSchools(JObject getSchoolsModel)
{
using (var client = new HttpClient())
{
               
var responseTask = await client.PostAsJsonAsync( requestUrl, getSchoolsModel);
                
}

}

How to call a endpoint in .Net core with request object

4 Answers4