Business
Jobs
  • About Us
  • Solutions
    • Job Postings
      Post your job and receive qualified candidates in 48h.
    • Candidate Assessments
      500+ technical and psychological tests, plus anti-fraud.
    • Headhunting
      Tailor-made executive search from start to finish.
    • Payroll + EOR
      Payroll dispersal and EOR across 15+ LATAM countries.
  • Pricing
  • Jobs

0

677
Views
MediatR IPipelineBehavior<TRequest, TResponse> errors as The type 'TRequest' cannot be used as type parameter 'TRequest' in the generic type or method

I'm using MediatR to do Request - Response logging in my application using IPipelineBehavior<TRequest, TResponse>

Code Sample:

internal sealed class AppLoggingBehavior<TRequest, TResponse> : IPipelineBehavior<TRequest, TResponse>
{
    private readonly ILogger<AppLoggingBehavior<TRequest, TResponse>> _logger;

    public AppLoggingBehavior(ILogger<AppLoggingBehavior<TRequest, TResponse>> logger)
    {
        _logger = logger;
    }

    public async Task<TResponse> Handle(TRequest request, CancellationToken cancellationToken, RequestHandlerDelegate<TResponse> next)
    {
        string requestName = typeof(TRequest).Name;
        string unqiueId = Guid.NewGuid().ToString();
        string requestJson = JsonSerializer.Serialize(request);
        _logger.LogInformation($"Begin Request Id:{unqiueId}, request name:{requestName}, request json:{requestJson}");
        var timer = new Stopwatch();
        timer.Start();
        var response = await next();
        timer.Stop();
        _logger.LogInformation($"End Request Id:{unqiueId}, request name:{requestName}, total request time:{timer.ElapsedMilliseconds}ms");
        return response;
    }
}

But After upgrading to Nuget - v10.0.0 I started getting the below compilation error.

The type 'TRequest' cannot be used as type parameter 'TRequest' in the generic type or method 'IPipelineBehavior<TRequest, TResponse>'. There is no boxing conversion or type parameter conversion from 'TRequest' to 'MediatR.IRequest'

I managed to find the porting guide from official MediatR repo. But couldn't find any examples.

Am I missing something else, Please can anyone assist me on this?

over 4 years ago · Santiago Trujillo
1 answers
Answer question

0

You need to specify the type of your TRequest parameter in your abstract class as well. It has to be at least specific as the parameter in the interface you're trying to implement.

internal sealed class AppLoggingBehavior<TRequest, TResponse>
    : IPipelineBehavior<TRequest, TResponse>
    where TRequest : MediatR.IRequest<TResponse> // <- this is the part you're missing
{
    // rest of your code...
}
over 4 years ago · Santiago Trujillo Report
Answer question
Find remote jobs

Discover the new way to find a job!

Top jobs
Top job categories
Business
Post vacancy Pricing Sales
Legal
Terms and conditions Privacy policy
© 2026 PeakU Inc. All Rights Reserved.
Andres GPT
Show me some job opportunities
There's an error!