Microsoft.AspNetCore.OpenApi -> MapOpenApi does not work with Microsoft.OpenApi (version 2.0.0)

[VYDocuWare]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

Hello.

Microsoft.AspNetCore.OpenApi -> app.MapOpenApi(); does not work when the referenced version of Microsoft.OpenApi is 2.0.0. On app.Run(), I get

'Could not load type 'Microsoft.OpenApi.Models.OpenApiDocument' from assembly 'Microsoft.OpenApi, Version=2.0.0.0

Expected Behavior

The app starts without issue.

Steps To Reproduce

Here is a reproduction repository: https://github.com/VYDocuWare/OpenApiReproduction

Try to run the project, and you'll get the error.

Exceptions (if any)

'Could not load type 'Microsoft.OpenApi.Models.OpenApiDocument' from assembly 'Microsoft.OpenApi, Version=2.0.0.0

.NET Version

9.0.301

Anything else?

No response

[martincostello]

This is expected - Microsoft.OpenApi 2.0.0 contains significant breaking changes, including type renames and moves.

.NET 8/9 cannot be updated from 1.x as it would be a breaking change, so you cannot use Microsoft.AspNetCore.OpenApi versions before .NET 10 with Microsoft.OpenApi 2.0.0.

[dotnet-policy-service]

This issue has been resolved and has not had any activity for 1 day. It will be closed for housekeeping purposes.

See our Issue Management Policies for more information.

[jnormen]

This is expected - Microsoft.OpenApi 2.0.0 contains significant breaking changes, including type renames and moves.

.NET 8/9 cannot be updated from 1.x as it would be a breaking change, so you cannot use Microsoft.AspNetCore.OpenApi versions before .NET 10 with Microsoft.OpenApi 2.0.0.

This was interesting, why did no one provide that information in this case? And why is it not marked add prev till 10 is released if this it the case? This just made nuget hell for us...

[martincostello]

And why is it not marked add prev till 10

It's not part of .NET - it just happens to be a Microsoft open source library that ASP.NET Core depends on. Its release schedule is completely independent of the .NET teams.

[jnormen]

And why is it not marked add prev till 10

It's not part of .NET - it just happens to be a Microsoft open source library that ASP.NET Core depends on. Its release schedule is completely independent of the .NET teams.

I see, :( sad