12,401 questions
Score of 0
1 answer
130 views
Swashbuckle.AspNetCore 10.1.7: OpenApiSecuritySchemeReference works but responses like 401 show as “Undocumented” in Swagger UI
I'm using Swashbuckle.AspNetCore version 10.1.7 with the new OpenAPI setup in .NET.
My Swagger security configuration looks like this:
services.AddSwaggerGen(options =>
{
options....
- reputation score 1
Score of 1
1 answer
316 views
Microsoft.OpenApi.Models Namespace Not Found Even After Installing Swagger/OpenAPI Package
I’m super confused today
Usually I configure Swagger in my ASP.NET Core APIs without issues, but now the OpenAPI/Swagger setup is throwing this error:
The type or namespace name 'Models' does not ...
- reputation score 11
Score of 3
1 answer
89 views
Swagger UI endpoint not exposed
I specified a custom Swagger UI endpoint.
springdoc:
swagger-ui:
path: /swagger-ui
However, I get 404 when hitting it from my browser:
http://localhost:8080/swagger-ui
2026-05-08T20:00:23.390+...
- reputation score 3089
Score of 0
0 answers
81 views
NestJS Swagger UI loads on real Android device but "Try it out" fails with CORS / Failed to fetch
I am developing a NestJS backend and testing it on a real Android device.
The Setup:
Backend IP: 192.168.1.5:3000 (MacBook)
Device: Real Android phone connected to the same Wi-Fi.
Observation: I ...
- reputation score 11
Score of 2
0 answers
113 views
Defining an OpenAPI Spec for an Endpoint with a Generic Body
We define our APIs using OpenApi 3. We are using Spring-Boot on the back-end.
We need to define an endpoint to receive notifications from arbitrary third parties. We will have a URL parameter for ...
- reputation score 6852
Score of -1
1 answer
95 views
Authorize filter attribute is returning signing key error, whereas it is 100% correct
I'm configuring authorization in my ASP.NET Core 8 project, and I get this error while testing JWT token auth via Swagger:
content-length: 0 date: Sun,12 Apr 2026 01:37:08 GMT server: Kestrel www-...
- reputation score 17
Advice
1
vote
3
replies
103
views
What is the correct way to build and run a command-line ASP.NET WebApplication?
I'm using Rider to develop a C# application that uses ASP.Net to create a simple web application. From inside the IDE, I can run and I get what I expect: A command-line application that runs in the ...
- reputation score 2142
Score of 0
0 answers
66 views
Using Swagger with Dropwizard - can't get non-root path to work correctly
We have a Dropwizard application which uses https://github.com/smoketurner/dropwizard-swagger to provide an interactive Swagger page. Normally we just serve the application on the root path and ...
- reputation score 1
Best practices
2
votes
2
replies
385
views
Best API documentation tool for a multi-service architecture (Swagger/OpenAPI vs Redoc vs Postman)?
I’m working on a backend system that follows a multi-service architecture (multiple microservices). Each service exposes its own REST APIs, and we want to provide clear and maintainable API ...
- reputation score 1
Score of 2
1 answer
193 views
How to serialize Date in response without breaking Swagger / OpenAPI?
I'm building a NestJS API using the nestjs-zod package for request/response validation and Swagger generation.
I have a domain entity like this:
export class UserEntity {
constructor(
...
- reputation score 41
Score of 3
0 answers
149 views
Swagger error 502 Bad Gateway, on NestJS/Railway [closed]
I'm getting a 502 Bad Gateway error when trying to access my Swagger API after deploying my NestJS backend to Railway.
Problem
The backend container starts fine, logs show the NestJS app is running ...
- reputation score 39
Score of 0
1 answer
75 views
.yaml not added to group URL
When I change the property springdoc.swagger-ui.url to contain the .yaml extension, for example /v3/api-docs.yaml, I expect the URLs of the defined groups to include it as well.
For example, with the ...
- reputation score 65
Score of 2
1 answer
82 views
What is the purpose of springdoc.group-configs[_].display-name if Swagger UI derives the group display name from SwaggerUrl instead
I'm trying to understand the relationship between groups and URLs in Springdoc.
For example, we might have the following Springdoc configuration:
springdoc.swagger-ui.urls[0].url=${springdoc.swagger-...
- reputation score 65
Score of 0
1 answer
197 views
Swagger UI fails to load with "Internal Server Error /swagger/v1/swagger.json" on ASP.NET Core 9 with file upload endpoint
I have an ASP.NET Core 9 Web API with a file upload endpoint using IFormFile. When I launch the application, Swagger UI fails to load with this error:
Failed to load API definition.
Fetch error
...
- reputation score 64
Score of 0
0 answers
142 views
Creation of semi-duplicate definitions leads to display problems (problem became visible when transitioning from springdoc 1.6.13 to springdoc 2.8.14)
When a Spring Boot application using springdoc-openapi-{common, ui, web-code, ...}:1.6.13 starts, it invokes the SwaggerWelcomeWebMvc class and later AbstractSwaggerWelcome, where ...
- reputation score 65