Why NSwag doesn't generate model from request?

[DragonDara]

Hi, there!

I have REST API on .NET Core 3.1 and we use NSwag to generate client code(typescript).

It works well except for one thing. Nswag doesn't generate a model in the request query.

/// <summary>
/// Get SNT report by filters
/// </summary>
[RoleAuthorize(RoleTypes = new RoleType[] { RoleType.SntOperator, RoleType.SntReadOnly, RoleType.TCOWarehouse })]
[HttpGet("get-snt-report")]
[ProducesResponseType(StatusCodes.Status200OK)]
[ProducesResponseType(StatusCodes.Status401Unauthorized)]
[ProducesResponseType(StatusCodes.Status403Forbidden)]
[SwaggerResponse(typeof(FileStreamResult))]
public async Task<IActionResult> GetSntReport([FromQuery] SntListFilter filter, CancellationToken cancellationToken)
{
    var stream = await _sender.Send(new GetSntReportQuery(filter), cancellationToken);
    return File(stream, "text/plain", "SNT-report.txt");
}

After generating, I get the following typescript code:

getSntReport(dateFrom?: Date | null | undefined, dateTo?: Date | null | undefined, type?: SntType | null | undefined, status?: SntStatus | null | undefined, borderCrossingDateFrom?: Date | null | undefined, borderCrossingDateTo?: Date | null | undefined, lastUpdateDateFrom?: Date | null | undefined, lastUpdateDateTo?: Date | null | undefined, sellerTin?: string | null | undefined, customerTin?: string | null | undefined, number?: string | null | undefined, registrationNumber?: string | null | undefined, declarationNumberForSnt?: string | null | undefined, carModel?: string | null | undefined, carStateNumber?: string | null | undefined): Observable<FileResponse>

I searched the Internet for answers, but I failed.
Does nswag support such functionality? If yes, what should I use?

Regards,
Darkhan

[ViRuSTriNiTy]

You should use the generic IActionResult<> interface to specify the result type. You can also specify the return type by attributing the action like [ProducesResponseType(typeof(MyReturnType), ...)].

[DragonDara]

You should use the generic IActionResult<> interface to specify the result type. You can also specify the return type by attributing the action like [ProducesResponseType(typeof(MyReturnType), ...)].

No, You got me wrong. I retrieved successfully return type in generated code . My issue is to generate a model that in request as the param of the controller method.

SntListFilter model isn't generated by Nswag. So I struggle to resolve it.

[ViRuSTriNiTy]

Ok, so it seems you have the same issue here as I already reported in #3301, see the comments why it is that way.

Simply put, there is not solution right now and you have to live with simple parameters. I did try to change the NSwag sources to generate a model, I remember it being pretty hard effort but then I got distracted and could never finish the change and provide a proof of concept (if that is even possible).

[DragonDara]

Ok, so it seems you have the same issue here as I already reported in #3301, see the comments why it is that way.

Simply put, there is not solution right now and you have to live with simple parameters. I did try to change the NSwag sources to generate a model, I remember it being pretty hard effort but then I got distracted and could never finish the change and provide a proof of concept (if that is even possible).

Thanks for truly reply) Is it possible to tell Nswag to generate a particular model?

[ViRuSTriNiTy]

Is it possible to tell Nswag to generate a particular model?

No as NSwag flattens the class properties (in your case the propertiers of SntListFilter) to a simple parameter list. @RicoSuter mentioned the underlying reason for this

#3301 (comment)

I think the main "problem" is that OpenAPI/Swagger has no notion to describe that directly

As I already wrote, I tried to find a solution for it but I could not finish my solution so that it can be merged.

[DragonDara]

Thanks a lot for helping me

[alpha-nero1]

Hi There @DragonDara after playing around with the same issue, I found that using [FromBody] instead of [FromQuery] makes nswag generate the request dto for you instead of the annoying endless params.

So for instance create(title: string, description: string...) will be turned into:
create(request: Command)

Hope this helps if anyone else runs into this issue,
Thanks

[DragonDara]

Ohh. Thank you a lot for this response. It has been long time since I posted this issue and it still remains unresolved in my team. I will check your resolution mandatory

…

On Mon, Mar 13, 2023, 14:57 alpha-nero1 ***@***.***> wrote: Hi There @DragonDara <https://github.com/DragonDara> after playing around with the same issue, I found that using [FromBody] instead of [FromQuery] makes nswag generate the request dto for you instead of the annoying endless params. So for instance create(title: string, description: string...) will be turned into: create(request: Command) Hope this helps if anyone else runs into this issue, Thanks — Reply to this email directly, view it on GitHub <#3486 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AIXPDNJVUPJSSO3IGHXPFYLW33VRBANCNFSM45UDRUBA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[ramax495]

Hi There @DragonDara after playing around with the same issue, I found that using [FromBody] instead of [FromQuery] makes nswag generate the request dto for you instead of the annoying endless params.

So for instance create(title: string, description: string...) will be turned into: create(request: Command)

Hope this helps if anyone else runs into this issue, Thanks

It really generates DTO-s, but GET-methods on backend has been broken and error is thrown - "A non-empty request body is required".

[goors]

This can not be done for Get, it will brake any Dto that you have into params ... sucks...
I will try this #3301 (comment)

[Mkrager]

Does anyone know the solution?