Nswag: "Consumes" attribute on controller action ignored

[georgeonofrei]

"Consumes" attribute on controller action does not generate the swagger.json with a "path" with the indicated "consumes" property

[RicoSuter]

Can you provide a sample action method and the expected swagger json?

[RicoSuter]

[ConsumesAttribute]

https://docs.microsoft.com/en-us/aspnet/core/api/microsoft.aspnetcore.mvc.consumesattribute

[georgeonofrei]

I expect the consume attribute to generate the right section in open api. Usually the consumes per action means an overwrite of the configured per website consumes.
I have a situation in which the web api usually consumes Json, but some actions consume form/encoded.

[TheSilvermind]

I noticed this is still an open issue. Is there any progress on this? Or can I do this any another way?

[RicoSuter]

Can you provide a sample operation to reproduce this?

[RicoSuter]

I've created a PR: Can you check the test and the rest? Is this what you'd expect?

https://github.com/RSuter/NSwag/pull/1849

[TheSilvermind]

Yes, this works. The Try it out functionallity is working now with the proper Content-Type. Sorry I could not reply to you sooner, but thanks very much for taking your time. Very much appreciated.

[LockTar]

@RSuter any idea when the PR will be merged? Is it correct that we can use the Consumes attribute on Action methods for ASP .NET Core?

[RicoSuter]

@LockTar will check ASAP. There must have been some problems otherwise i would have merged it :-)

[LockTar]

Hi @RSuter, did you found an issue?

[RicoSuter]

See @pranavkm answer in the PR:

ConsumesAttribute works in tandem with formatters - the idea is that you can only consume a media type that you could read from the body. It's likely that there isn't a formatter for text/html in your test above. Here's the relevant piece of code: https://github.com/aspnet/AspNetCore/blob/master/src/Mvc/src/Microsoft.AspNetCore.Mvc.ApiExplorer/DefaultApiDescriptionProvider.cs#L426-L461

[LockTar]

Hi @RSuter, sorry I don't understand your reply. I checked the PR but I think I do the same as in the PR.
I have a Controller with the attributes:

```c#
[Produces("application/json")]
[ApiController]

I than have an action with the following attributes:

```c#
[HttpPost("add")]
[Consumes("application/json")]
[ProducesResponseType(201)]
[ProducesResponseType(400)]

In the swagger.json, in the "add" path i have:

"consumes": [
"application/json-patch+json",
"application/json",
"application/*+json"
]

The api works as expected with application/json as contenttype.

[RicoSuter]

So is this what you expect? Or do you want a different outcome?

[LockTar]

I was only expecting "application/json" because that is in the Consumes attribute.

[RicoSuter]

I think the other types are registered globally in asp.net core startup or introduced by the used api convention

[LockTar]

I think "application/json-patch+json" and "application/*+json" are part of the default then. I can't find anything in the documentation about this.

[TheSilvermind]

It doesn't matter if they are automatically added globally, because the way asp core works is that if you have a Consumes attribute, it will only accept that type. So it makes sense to support this feature. This is easily tested btw.

[LockTar]

It doesn't matter if they are automatically added globally, because the way asp core works is that if you have a Consumes attribute, it will only accept that type. So it makes sense to support this feature. This is easily tested btw.

@TheSilvermind So… You would expect also that if you have a Consume attribute [Consumes("application/json")] on your action that you would only see the following?

"consumes": [
"application/json"
]

[TheSilvermind]

Yes, because if I apply the attribute and choose another mime type in the swagger 'try it out' functionallity, an exception is thrown that the provided mime type is not supported.

[RicoSuter]

These mime types are reported by ASP.NET Core - so I think they are part of the default API Convention or automatically added...

[TheSilvermind]

@RSuter @LockTar Sorry, you're right. I wasn't paying proper attention. It seems it was the text mime-type that caused problems, but that one seems no longer generated as previously reported.

[cdutcher]

I'm not seeing [Consumes("text/plain")] respected. Using NSwag.AspNetCore 12.3.1

[kbsanders]

It appears that for OpenAPI spec generation, the MIME type for content is hardcoded to application/json (or application/octet-stream for binary files).

https://github.com/RicoSuter/NSwag/blob/4e94b9d2bd558eb7bc2fa5f944b6a3ff08d62c68/src/NSwag.Core/OpenApiResponse.cs#L73-L86

My API will produce JSON:API formatted documents so I need to be able to set the content type to application/vnd.api+json.

Currently, the only way I have found to achieve this is via a PostProcess action where I traverse down through the Operations and Responses of the generated spec and remove/replace application/json keyed Content items with application/vnd.api+json.

services.AddOpenApiDocument(config =>
{
    config.PostProcess = document =>
    {
        const string fromKey = "application/json";
        const string toKey = "application/vnd.api+json";

        foreach (var o in document.Operations)
        {
            foreach (var r in o.Operation.Responses)
            {
                if (r.Value.Content.TryGetValue(fromKey, out var value))
                {
                    r.Value.Content.Remove(fromKey);
                    r.Value.Content.Add(toKey, value);
                }
            }
        }
    }
});

[silvairsoares]

I have the same problem ([Consumes ("text / plain")] ignored). I even opened this question on the stackoverflow in an attempt to get some help.