skipped queue in MassTransit with RabbitMQ in dot net core application

Question

I have three projects. One is Dot net core MVC, two are API projects. MVC is calling one API for user details. When user details are asked, I am sending message to queue through MassTransit. I am seeing skipped queue. There's consumer in third project which is API project.

I tried to make another solution for a demo with same configuration. It's running fine.

Below is MVC Razor page code..

public async Task<IActionResult> OnPostAsync(string returnUrl = null)
    {
        ReturnUrl = returnUrl;

        if (ModelState.IsValid)
        {
            var user = await AuthenticateUser(Input.Email);

            if (user == null)
            {
                ModelState.AddModelError(string.Empty, "Invalid login attempt.");
                return Page();
            }

            #region snippet1
            var claims = new List<Claim>
            {
                new Claim(ClaimTypes.Name, user.Email),
                new Claim("FullName", user.FullName),
                new Claim(ClaimTypes.Role, "Administrator"),
            };

            var claimsIdentity = new ClaimsIdentity(
                claims, CookieAuthenticationDefaults.AuthenticationScheme);

            var authProperties = new AuthenticationProperties
            {
                ExpiresUtc = DateTimeOffset.UtcNow.AddMinutes(15),
                IsPersistent = true,
            };

            await HttpContext.SignInAsync(
                CookieAuthenticationDefaults.AuthenticationScheme,
                new ClaimsPrincipal(claimsIdentity),
                authProperties);
            #endregion

            _logger.LogInformation("User {Email} logged in at {Time}.",
                user.Email, DateTime.UtcNow);

            return LocalRedirect(Url.GetLocalUrl(returnUrl));
        }

        return Page();
    }

    private async Task<ApplicationUser> AuthenticateUser(string email)
    {
        if (!string.IsNullOrEmpty(email))
        {
            using (var client = new System.Net.Http.HttpClient())
            {
                var request = new System.Net.Http.HttpRequestMessage();
                request.RequestUri = new Uri("http://localhost:52043/api/user?uName=" + email); // ASP.NET 3 (VS 2019 only)
                var response = await client.SendAsync(request);
                var customer = Newtonsoft.Json.JsonConvert.DeserializeObject<Customers>(response.Content.ReadAsStringAsync().Result);

                
                return new ApplicationUser()
                {
                    Email = email,
                    FullName = customer.FullName
                };
            }
        }
        else
        {
            return null;
        }
    }

MVC Startup:

services.AddMassTransit(x =>
        {
            x.AddBus(provider => Bus.Factory.CreateUsingRabbitMq(cfg =>
            {
                // configure health checks for this bus instance
                cfg.UseHealthCheck(provider);

                cfg.Host("rabbitmq://localhost");

            }));
        });

        services.AddMassTransitHostedService();

User API Code - 52043:

[HttpGet]
    public async Task<IActionResult> Get(string uName)
    {
        var customer = _userRepository.GetCustomerByUserName(uName);

        Uri uri = new Uri("rabbitmq://localhost/loginqueue");
        var endpoint = await _bus.GetSendEndpoint(uri);
        await endpoint.Send(new LoginObj() { NoteString = customer.FullName + " has logged in at " + DateTime.Now.ToString() });
        
        return Json(customer);
    }

Logging API - Consumer Code:

public class LoginConsumer : IConsumer<LoginObj>
{
    private readonly ILogger<object> _logger;

    public LoginConsumer(ILogger<object> logger)
    {
        _logger = logger;
    }

    public async Task Consume(ConsumeContext<LoginObj> context)
    {
        var data = context.Message;
        _logger.LogInformation(data.ToString());
    }
}

Login API Startup:

services.AddMassTransit(x =>
        {
            x.AddConsumer<LoginConsumer>();

            x.AddBus(provider => Bus.Factory.CreateUsingRabbitMq(cfg =>
            {
                // configure health checks for this bus instance
                cfg.UseHealthCheck(provider);

                cfg.Host("rabbitmq://localhost");

                cfg.ReceiveEndpoint("loginqueue", ep =>
                {
                    ep.PrefetchCount = 16;
                    ep.UseMessageRetry(r => r.Interval(2, 100));

                    ep.ConfigureConsumer<LoginConsumer>(provider);
                });
            }));
        });

        services.AddMassTransitHostedService();

Answer 1

As per the documentation:

MassTransit uses the full type name, including the namespace, for message contracts. When creating the same message type in two separate projects, the namespaces must match or the message will not be consumed.

Make sure that your message type has the same namespace/type in each project.