Is it possible to call synchronous http post request using ASP.net? - asp.net

Question

I have a scenario where http POST request execute, call another get request and return response of get request. Here is my code
public class EmployeeController : ControllerBase
{
private readonly IBusControl _bus;
public EmployeeController(IBusControl bus)
{
_bus = bus;
}
[HttpPost]
public async Task<IActionResult> Emp(EmployeeModel employee)
{
Uri uri = new Uri("rabbitmq://localhost/ret_eligibility");
var endPoint = await _bus.GetSendEndpoint(uri);
await endPoint.Send(employee);
return Ok("Success");
}
[HttpGet]
[Route("getRetFund")]
public IActionResult fund()
{
Fund fund = RetFundConsumer.fund;
return Ok(fund.retfund);
}
}
I want to call getRetFund request in POST request method, So that when employee data is sent to queue using postman, it call second service which consume message and send response back. This response will be shown then in console.
I also have tried the following POST method.
[HttpPost]
public async Task<IActionResult> Emp(EmployeeModel employee)
{
Uri uri = new Uri("rabbitmq://localhost/ret_eligibility");
var endPoint = await _bus.GetSendEndpoint(uri);
await endPoint.Send(employee);
//return Ok("Success");
Fund fund = RetFundConsumer.fund;
return Ok("your retirement fund is " + fund.retfund);
}
But this throw null Exception as it call second service before executing POST request. The response would be greatly appreciated.

Answer 1

This would never work. You need to spend time about both Web API request handling scope and MassTransit message handling scope.
In short, both Web API and MassTransit message handling is scoped to one message. There is no way you can consume a response message, somehow magically keeping the HTTP session open. The consumer gets disposed when it finishes handling a message.
You can do it, though, but you need to use the MassTransit request/response feature.
public class EmployeeController : ControllerBase
{
private readonly IRequestClient<EmployeeModel> _client;
public EmployeeController(IClientFactory clientFactory)
=> _client = clientFactory.CreateRequestClient<EmployeeModel>(
new Uri("rabbitmq://localhost/ret_eligibility"));
[HttpPost]
public async Task<IActionResult> Emp(EmployeeModel employee)
{
var response = await _client.GetResponse<Fund>(employee);
return Ok("your retirement fund is " + fund.retfund);
}
}
Of course, you need to change your consumer accordingly to send a message back. Check the documentation referenced above for the details.