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Asp.Net Core FromBody parameter always null on angular PUT request

I try to update the identity of a worker on my project, I use HttpClient with a put, working in Angular 6 project and web API 2 on .NET Core. You can see here the request on the front-end side:
updateWorkerIdentity(worker: WorkerRead) : Observable<WorkerRead> {
const url = 'workerinfo/activeContractId=' + worker.activeContract.id;
return this.httpClient.put<WorkerRead>(url , JSON.stringify(worker) );
}
And at the API side:
[HttpPut("{activeContractId}")]
public async Task<IActionResult> Put([FromRoute] string activeContractId, [FromBody] WorkerRead worker)
{
var companyId = GetCompanyId();
var period = GetPeriod();
var language = GetLanguage();
var workerInfo = await _workerInfoService.UpdateWorkerIdentity(companyId, activeContractId, language, worker);
return Ok(workerInfo);
}
the activeContractId coming from the [FromRoute] is well sent but the worker is still null.
The worker sent from the body is well sent as you can see here in the payload:
and the Content-Type of the header is well application/JSON.
Anyone has an idea?

Everything on the server side looks OK for a simple endpoint.
However, based on the [HttpPut("{activeContractId}")] route template the request on the client side should be refactored to match the expected template
updateWorkerIdentity(worker: WorkerRead) : Observable<WorkerRead> {
const url = 'workerinfo/' + worker.activeContract.id;
return this.httpClient.put<WorkerRead>(url , worker);
}
I suspect that the httpClient will internally stringify the payload before sending.
The above code assumes the controller is defined
[Route("[controller]")]
public class WorkerInfoController : Controller {
//...
//PUT workerinfo/123456
[HttpPut("{activeContractId}")]
public async Task<IActionResult> Put([FromRoute] string activeContractId, [FromBody] WorkerRead worker) {
var companyId = GetCompanyId();
var period = GetPeriod();
var language = GetLanguage();
var workerInfo = await _workerInfoService.UpdateWorkerIdentity(companyId, activeContractId, language, worker);
return Ok(workerInfo);
}
}

Angular 2 POST JSON to C# API

Good Evening Community,
I am having problems to post data to a C# Api from Angular 2 POST methods. Practically I need to send a JSON object to the API. Below is the API POST method that is the endpoint.
[HttpPost]
public Boolean Update(BoRole role, Guid accessToken)
{
CheckUserSuperadmin(accessToken);
string JsonContent = Request.Content.ReadAsStringAsync().Result;
var roleEntity = BaseDependencies.RoleManager.GetRoleById(role.Id);
roleEntity.Name = role.Name;
roleEntity.AuthorizedThreshold = role.AuthorizedThreshold;
BaseDependencies.RoleManager.UpdateRole(roleEntity);
return true;
}
The following is my Angular 2 service, with the POST method.
// Update the Role
updateRole(role: Role, accessToken: string): any {
const body: any = JSON.stringify(role);
const headers = new Headers({'Content-Type': 'application/json'});
const options = new RequestOptions({ headers: headers });
const url = this.serverUrl + '/api/Role/Update?role=' + body + '&accessToken=' + accessToken;
return this.http.post(url, body, options).map((res: Response) => res.json());
}
To explain better, I am trying to send a JSON object to this API, but whenever I try to POST to the API the role object remains null, never tried to POST data this way. Is it possible?
Thanks

Change the Api to get only one get one body
[HttpPost("Add")]
public async Task<IActionResult> Post([FromBody]AddRequest value)
In my case the class
AddRequest
Have all the body structure that I need, in your case create one class that C# can automap (same names) and the rest is history in C#
At Angular
const url = this.serverUrl + '/api/Role/Update?role=' + body +
'&accessToken=' + accessToken;
change it for
const url = this.serverUrl + '/api/CONTROLLERNAME';
C# will detect that is a Post Request and map it to the right Http Call

Creating a proxy to another web api with Asp.net core

I'm developing an ASP.Net Core web application where I need to create a kind of "authentication proxy" to another (external) web service.
What I mean by authentication proxy is that I will receive requests through a specific path of my web app and will have to check the headers of those requests for an authentication token that I'll have issued earlier, and then redirect all the requests with the same request string / content to an external web API which my app will authenticate with through HTTP Basic auth.
Here's the whole process in pseudo-code
Client requests a token by making a POST to a unique URL that I sent him earlier
My app sends him a unique token in response to this POST
Client makes a GET request to a specific URL of my app, say /extapi and adds the auth-token in the HTTP header
My app gets the request, checks that the auth-token is present and valid
My app does the same request to the external web API and authenticates the request using BASIC authentication
My app receives the result from the request and sends it back to the client
Here's what I have for now. It seems to be working fine, but I'm wondering if it's really the way this should be done or if there isn't a more elegant or better solution to this? Could that solution create issues in the long run for scaling the application?
[HttpGet]
public async Task GetStatement()
{
//TODO check for token presence and reject if issue
var queryString = Request.QueryString;
var response = await _httpClient.GetAsync(queryString.Value);
var content = await response.Content.ReadAsStringAsync();
Response.StatusCode = (int)response.StatusCode;
Response.ContentType = response.Content.Headers.ContentType.ToString();
Response.ContentLength = response.Content.Headers.ContentLength;
await Response.WriteAsync(content);
}
[HttpPost]
public async Task PostStatement()
{
using (var streamContent = new StreamContent(Request.Body))
{
//TODO check for token presence and reject if issue
var response = await _httpClient.PostAsync(string.Empty, streamContent);
var content = await response.Content.ReadAsStringAsync();
Response.StatusCode = (int)response.StatusCode;
Response.ContentType = response.Content.Headers.ContentType?.ToString();
Response.ContentLength = response.Content.Headers.ContentLength;
await Response.WriteAsync(content);
}
}
_httpClient being a HttpClient class instantiated somewhere else and being a singleton and with a BaseAddressof http://someexternalapp.com/api/
Also, is there a simpler approach for the token creation / token check than doing it manually?

If anyone is interested, I took the Microsoft.AspNetCore.Proxy code and made it a little better with middleware.
Check it out here: https://github.com/twitchax/AspNetCore.Proxy. NuGet here: https://www.nuget.org/packages/AspNetCore.Proxy/. Microsoft archived the other one mentioned in this post, and I plan on responding to any issues on this project.
Basically, it makes reverse proxying another web server a lot easier by allowing you to use attributes on methods that take a route with args and compute the proxied address.
[ProxyRoute("api/searchgoogle/{query}")]
public static Task<string> SearchGoogleProxy(string query)
{
// Get the proxied address.
return Task.FromResult($"https://www.google.com/search?q={query}");
}

I ended up implementing a proxy middleware inspired by a project in Asp.Net's GitHub.
It basically implements a middleware that reads the request received, creates a copy from it and sends it back to a configured service, reads the response from the service and sends it back to the caller.

This post talks about writing a simple HTTP proxy logic in C# or ASP.NET Core. And allowing your project to proxy the request to any other URL. It is not about deploying a proxy server for your ASP.NET Core project.
Add the following code anywhere of your project.
public static HttpRequestMessage CreateProxyHttpRequest(this HttpContext context, Uri uri)
{
var request = context.Request;
var requestMessage = new HttpRequestMessage();
var requestMethod = request.Method;
if (!HttpMethods.IsGet(requestMethod) &&
!HttpMethods.IsHead(requestMethod) &&
!HttpMethods.IsDelete(requestMethod) &&
!HttpMethods.IsTrace(requestMethod))
{
var streamContent = new StreamContent(request.Body);
requestMessage.Content = streamContent;
}
// Copy the request headers
foreach (var header in request.Headers)
{
if (!requestMessage.Headers.TryAddWithoutValidation(header.Key, header.Value.ToArray()) && requestMessage.Content != null)
{
requestMessage.Content?.Headers.TryAddWithoutValidation(header.Key, header.Value.ToArray());
}
}
requestMessage.Headers.Host = uri.Authority;
requestMessage.RequestUri = uri;
requestMessage.Method = new HttpMethod(request.Method);
return requestMessage;
}
This method covert user sends HttpContext.Request to a reusable HttpRequestMessage. So you can send this message to the target server.
After your target server response, you need to copy the responded HttpResponseMessage to the HttpContext.Response so the user's browser just gets it.
public static async Task CopyProxyHttpResponse(this HttpContext context, HttpResponseMessage responseMessage)
{
if (responseMessage == null)
{
throw new ArgumentNullException(nameof(responseMessage));
}
var response = context.Response;
response.StatusCode = (int)responseMessage.StatusCode;
foreach (var header in responseMessage.Headers)
{
response.Headers[header.Key] = header.Value.ToArray();
}
foreach (var header in responseMessage.Content.Headers)
{
response.Headers[header.Key] = header.Value.ToArray();
}
// SendAsync removes chunking from the response. This removes the header so it doesn't expect a chunked response.
response.Headers.Remove("transfer-encoding");
using (var responseStream = await responseMessage.Content.ReadAsStreamAsync())
{
await responseStream.CopyToAsync(response.Body, _streamCopyBufferSize, context.RequestAborted);
}
}
And now the preparation is complete. Back to our controller:
private readonly HttpClient _client;
public YourController()
{
_client = new HttpClient(new HttpClientHandler()
{
AllowAutoRedirect = false
});
}
public async Task<IActionResult> Rewrite()
{
var request = HttpContext.CreateProxyHttpRequest(new Uri("https://www.google.com"));
var response = await _client.SendAsync(request, HttpCompletionOption.ResponseHeadersRead, HttpContext.RequestAborted);
await HttpContext.CopyProxyHttpResponse(response);
return new EmptyResult();
}
And try to access it. It will be proxied to google.com

A nice reverse proxy middleware implementation can also be found here: https://auth0.com/blog/building-a-reverse-proxy-in-dot-net-core/
Note that I replaced this line here
requestMessage.Content?.Headers.TryAddWithoutValidation(header.Key, header.Value.ToArray());
with
requestMessage.Headers.TryAddWithoutValidation(header.Key, header.Value.ToString());
Original headers (e.g. like an authorization header with a bearer token) would not be added without my modification in my case.

I had luck using twitchax's AspNetCore.Proxy NuGet package, but could not get it to work using the ProxyRoute method shown in twitchax's answer. (Could have easily been a mistake on my end.)
Instead I defined the mapping in Statup.cs Configure() method similar to the code below.
app.UseProxy("api/someexternalapp-proxy/{arg1}", async (args) =>
{
string url = "https://someexternalapp.com/" + args["arg1"];
return await Task.FromResult<string>(url);
});

Piggy-backing on James Lawruk's answer https://stackoverflow.com/a/54149906/6596451 to get the twitchax Proxy attribute to work, I was also getting a 404 error until I specified the full route in the ProxyRoute attribute. I had my static route in a separate controller and the relative path from Controller's route was not working.
This worked:
public class ProxyController : Controller
{
[ProxyRoute("api/Proxy/{name}")]
public static Task<string> Get(string name)
{
return Task.FromResult($"http://www.google.com/");
}
}
This does not:
[Route("api/[controller]")]
public class ProxyController : Controller
{
[ProxyRoute("{name}")]
public static Task<string> Get(string name)
{
return Task.FromResult($"http://www.google.com/");
}
}
Hope this helps someone!

Twitchax's answer seems to be the best solution at the moment. In researching this, I found that Microsoft is developing a more robust solution that fits the exact problem the OP was trying to solve.
Repo: https://github.com/microsoft/reverse-proxy
Article for Preview 1 (they actually just released prev 2): https://devblogs.microsoft.com/dotnet/introducing-yarp-preview-1/
From the Article...
YARP is a project to create a reverse proxy server. It started when we noticed a pattern of questions from internal teams at Microsoft who were either building a reverse proxy for their service or had been asking about APIs and technology for building one, so we decided to get them all together to work on a common solution, which has become YARP.
YARP is a reverse proxy toolkit for building fast proxy servers in .NET using the infrastructure from ASP.NET and .NET. The key differentiator for YARP is that it is being designed to be easily customized and tweaked to match the specific needs of each deployment scenario. YARP plugs into the ASP.NET pipeline for handling incoming requests, and then has its own sub-pipeline for performing the steps to proxy the requests to backend servers. Customers can add additional modules, or replace stock modules as needed.
...
YARP works with either .NET Core 3.1 or .NET 5 preview 4 (or later). Download the preview 4 (or greater) of .NET 5 SDK from https://dotnet.microsoft.com/download/dotnet/5.0
More specifically, one of their sample apps implements authentication (as for the OP's original intent)
https://github.com/microsoft/reverse-proxy/blob/master/samples/ReverseProxy.Auth.Sample/Startup.cs

Here is a basic implementation of Proxy library for ASP.NET Core:
This does not implement the authorization but could be useful to someone looking for a simple reverse proxy with ASP.NET Core. We only use this for development stages.
using System;
using System.Globalization;
using System.Linq;
using System.Net.Http;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Primitives;
namespace Sample.Proxy
{
public class Startup
{
public void ConfigureServices(IServiceCollection services)
{
services.AddLogging(options =>
{
options.AddDebug();
options.AddConsole(console =>
{
console.IncludeScopes = true;
});
});
services.AddProxy(options =>
{
options.MessageHandler = new HttpClientHandler
{
AllowAutoRedirect = false,
UseCookies = true
};
options.PrepareRequest = (originalRequest, message) =>
{
var host = GetHeaderValue(originalRequest, "X-Forwarded-Host") ?? originalRequest.Host.Host;
var port = GetHeaderValue(originalRequest, "X-Forwarded-Port") ?? originalRequest.Host.Port.Value.ToString(CultureInfo.InvariantCulture);
var prefix = GetHeaderValue(originalRequest, "X-Forwarded-Prefix") ?? originalRequest.PathBase;
message.Headers.Add("X-Forwarded-Host", host);
if (!string.IsNullOrWhiteSpace(port)) message.Headers.Add("X-Forwarded-Port", port);
if (!string.IsNullOrWhiteSpace(prefix)) message.Headers.Add("X-Forwarded-Prefix", prefix);
return Task.FromResult(0);
};
});
}
private static string GetHeaderValue(HttpRequest request, string headerName)
{
return request.Headers.TryGetValue(headerName, out StringValues list) ? list.FirstOrDefault() : null;
}
public void Configure(IApplicationBuilder app)
{
app.UseWebSockets()
.Map("/api", api => api.RunProxy(new Uri("http://localhost:8833")))
.Map("/image", api => api.RunProxy(new Uri("http://localhost:8844")))
.Map("/admin", api => api.RunProxy(new Uri("http://localhost:8822")))
.RunProxy(new Uri("http://localhost:8811"));
}
public static void Main(string[] args)
{
var host = new WebHostBuilder()
.UseKestrel()
.UseIISIntegration()
.UseStartup<Startup>()
.Build();
host.Run();
}
}
}

ServiceStack - As passthru to another ServiceStack service

I currently have an ServiceStack Service that does nothing but relay requests to an internal ServiceStack service.
The relay service is setup something like this (code made brief as an example):
public class RelayService : Service
{
public SomeDTO Get(FetchSomething request)
{
try
{
return new JsonServiceClient(settings.OtherServiceURL).Get(request);
}
catch (Exception)
{
throw;
}
}
public void Put(PersistSomething request)
{
try
{
new JsonServiceClient(settings.OtherServiceURL).Put(request);
}
catch (Exception)
{
throw;
}
}
}
My questions are:
Is it best practice to new up a JsonServiceClient for each request? Or should I inject an instance?
Since the relay service can contain variations on Put/Get that return DTO's or void, is there a cleaner way to relay all calls to the backing ServiceStack service instead of having to duplicate each method in the relay service? Is it possible to do this all in one or a few methods using Any()?
Thanks for any input.

This previous answer for an example of a generic reverse proxy in ServiceStack.
The simplest and most generic approach in ServiceStack would be to register a RawHttpHandler that just forwards the Request to the downstream server and writes the Response to the Output Stream, e.g:
RawHttpHandlers.Add(_ => new CustomActionHandler((req, res) =>
{
var bytes = req.InputStream.ReadFully();
var proxyUrl = settings.OtherServiceURL.CombineWith(req.RawUrl);
var responseBytes = proxyUrl.SendBytesToUrl(method: req.Verb,
requestBody: bytes,
accept:MimeTypes.Json,
contentType: req.ContentType,
responseFilter: webRes =>
{
res.StatusCode = (int)webRes.StatusCode;
res.StatusDescription = webRes.StatusDescription;
res.ContentType = webRes.ContentType;
});
res.OutputStream.Write(responseBytes, 0, responseBytes.Length);
}));
In order to access the RequestStream you'll also want to tell ServiceStack to not inspect the FormData when creating the Request (as this forces reading the request body), which you can skip with:
SetConfig(new HostConfig {
SkipFormDataInCreatingRequest = true
});
Another approach would be to configure something like IIS Application Request Routing and URL Rewriting to use as a reverse proxy.

What is the ASP.NET Core MVC equivalent to Request.RequestURI?

I found a blog post that shows how to "shim" familiar things like HttpResponseMessage back into ASP.NET Core MVC, but I want to know what's the new native way to do the same thing as the following code in a REST Post method in a Controller:
// POST audit/values
[HttpPost]
public System.Net.Http.HttpResponseMessage Post([FromBody]string value)
{
var NewEntity = _repository.InsertFromString(value);
var msg = new System.Net.Http.HttpResponseMessage(System.Net.HttpStatusCode.Created);
msg.Headers.Location = new Uri(Request.RequestUri + NewEntity.ID.ToString());
return msg;
}
In an ASP.NET Core MVC project, I can't seem to get Request.RequestUri.
I tried inspecting Request, and I was able to make a function like this:
private string UriStr(HttpRequest Request)
{
return Request.Scheme + "://" + Request.Host + Request.Path; // Request.Path has leading /
}
So I could write UriStr(Request) instead. But I'm not sure that's right. I feel like I'm hacking my way around, and not using this correctly.
A related question for earlier non-Core ASP.NET MVC versions asks how to get the base url of the site.

Personally, I use :
new Uri(request.GetDisplayUrl())
GetDisplayUrl fully un-escaped form (except for the QueryString)
GetEncodedUrl - fully escaped form suitable for use in HTTP headers
These are extension method from the following namespace : Microsoft.AspNetCore.Http.Extensions

A cleaner way would be to use a UriBuilder:
private static Uri GetUri(HttpRequest request)
{
var builder = new UriBuilder();
builder.Scheme = request.Scheme;
builder.Host = request.Host.Value;
builder.Path = request.Path;
builder.Query = request.QueryString.ToUriComponent();
return builder.Uri;
}
(not tested, the code might require a few adjustments)

Here's a working code. This is based off #Thomas Levesque answer which didn't work well when the request is from a custom port.
public static class HttpRequestExtensions
{
public static Uri ToUri(this HttpRequest request)
{
var hostComponents = request.Host.ToUriComponent().Split(':');
var builder = new UriBuilder
{
Scheme = request.Scheme,
Host = hostComponents[0],
Path = request.Path,
Query = request.QueryString.ToUriComponent()
};
if (hostComponents.Length == 2)
{
builder.Port = Convert.ToInt32(hostComponents[1]);
}
return builder.Uri;
}
}