How to set the root path of the url for my api endpoints?

Question

I don't want to use UsePathBase() for some reasons. I try to use MapExtensions.Map() like below. But it does not work. Respond with "404 Not Found" when I request "/api/v1/WeatherForecast".By the way, this endpoint url is "/WeatherForecast", but respond with "404 Not Found" either.

using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.Configuration;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

var configuration = builder.Configuration.
                            AddEnvironmentVariables()
                            .SetBasePath(System.IO.Directory.GetCurrentDirectory())
                            .Build();

var app = builder.Build();

app.UseDefaultFiles();
app.UseStaticFiles();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.Map("/api/v1", apiApp =>
{
    apiApp.UseRouting();

    apiApp.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
});

app.MapFallbackToFile("/index.html");

app.Run();

I want to set the root path by app.Map().

Answer 1

You can use the PathBase (via the UsePathBase call):

app.UsePathBase("/api");
app.UseRouting();

app.UseAuthorization();
    
app.MapControllers();

note that this will make both your controller available via both api/controller and controller routes.

As for your approach - for .NET 8 adding explicit call to app.UseRouting() makes the controllers available (for .NET 9 seems to be working fine without it):

app.Map("/api", apiApp =>
{
    apiApp.UseRouting();

    apiApp.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
});
app.UseRouting();