aspnetcore: UsePathBase being ignored

Describe the bug

UsePathBase seems to get ignored. I’m not sure what the condition is. In my other project, it works with the Swagger endpoints, but not with the controllers. In this repro, it works with neither. In both cases, it’s the first call I make after I build the app.

To Reproduce

Create a new Web API project
Call app.UsePathBase() immediately after var app = builder.Build()
Run the project, open root (non-UsePathBase) URL in browser

https://github.com/reinux/UsePathBaseTest

Exceptions (if any)

Further technical details

ASP.NET Core version: 6.0.0.0
The IDE (VS / VS Code/ VS4Mac) you’re running on, and its version: VS2022
Include the output of dotnet --info:

dotnet --info Output

.NET SDK (reflecting any global.json):
 Version:   6.0.100
 Commit:    9e8b04bbff

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22000
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\6.0.100\

Host (useful for support):
  Version: 6.0.0
  Commit:  4822e3c3aa

.NET SDKs installed:
  3.1.415 [C:\Program Files\dotnet\sdk]
  5.0.103 [C:\Program Files\dotnet\sdk]
  5.0.104 [C:\Program Files\dotnet\sdk]
  5.0.209 [C:\Program Files\dotnet\sdk]
  5.0.303 [C:\Program Files\dotnet\sdk]
  5.0.402 [C:\Program Files\dotnet\sdk]
  5.0.403 [C:\Program Files\dotnet\sdk]
  6.0.100 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.20 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.20 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.0-rc.2.20475.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.1.19 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.20 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.21 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.11 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.12 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET runtimes or SDKs:
  https://aka.ms/dotnet-download

About this issue

Original URL
State: closed
Created 3 years ago
Reactions: 11
Comments: 19 (6 by maintainers)

Most upvoted comments

I hit this today and I couldn’t find it documented anywhere yet. Is there an issue tracking this for the docs? I tried looking at the Minimal APIs page and any page referencing PathBase

I submitted a docs PR at https://github.com/dotnet/AspNetCore.Docs/pull/25769 to add notes mentioning the need to call UseRouting() where we mention UsePathBase. Hopefully we can remove these notes in .NET 7 once we fix this issue.

halter73 on Apr 28, 2022

I think an analyzer is a good idea here. FWIW, you should be able to just add .UseRouting() without .UseEndpoints() to change where the route matching happens.

halter73 on Nov 17, 2021

app.UseRouting(); does not seem to work for the new minimal api

Xyotic on Mar 4, 2022

Something we can document for now and then we can do what we did for the other middleware that rewrites the path.

cc @BrennanConroy

davidfowl on Nov 17, 2021