Nswag: Multiple file upload via UI

[Fedorus]

Is there a way to send multiple files in one request using:

app.UseSwaggerUi(typeof(Startup).GetTypeInfo().Assembly, settings =>{
               settings.UseJsonEditor = true;
            });

first of all it allows selection of only 1 file.
And after that in file: NSwag.AspNet.Owin/SwaggerUi/swagger-ui.js it just doesn`t add files:

      if (o.type === 'file') {
        map[o.name] = o.files[0];
      }

[RicoSuter]

Seems to be a problem with swagger ui and not nswag. Did you try SwaggerUi3? Is the generated swagger spec correct? Where did you find the last code snippet?

[Fedorus]

Where did you find the last code snippet?

link

Is the generated swagger spec correct?

Yes, spec is correct.

Did you try SwaggerUi3?

Hm, I`ll look on it today, thanks.

[Fedorus]

Same thing with 3rd version. HTTP side doesn`t use "multiple" atribute and if you add it will still send only first file.
The generated side looks good:

{ "type": "file", "name": "files", "in": "formData", "collectionFormat": "multi", "x-nullable": true, "items": { "type": "file" }

[RicoSuter]

Maybe you should check with the Swagger UI 3 guys whether this is supported and correct Swagger spec?

https://github.com/swagger-api/swagger-ui

[barmyard]

Yes there is, the following shows a file upload for me, in both Swagger UI 2 and 3 :

public async Task<List<X>> X([FromForm] IFormFile file1, [FromForm] IFormFile file2)
{
            file1 = this.HttpContext.Request.Form.Files[0];
            file2 = this.HttpContext.Request.Form.Files[1];

For some reason the files are not bound correctly by ASP.NET Core, so that's why I get it manually from the request's context.

Which brings me to the following problem: The above approach only works for app.UserSwaggerUi(3), if I'm using the new ApiExplorer approach, the file upload is not recognized, as can be seen in the following screencap:

[ranouf]

Hi,

I try to transfer an array of IFile from Angular to .Net Core.
It seems that I have the same issue. my variable [FromForm] has all properties to null.

Did you find a way to bind it automatically?

here is my Dto

Server:

    public class SampleDto
    {
        public Guid Id{ get; set; }
        public string Text { get; set; }
        public IEnumerable<string> ImageUrl { get; set; }
        public IEnumerable<IFormFile> Image { get; set; }
    }

        [HttpPut]
        [Route("{id:guid}")]
        public async Task<IActionResult> UpdateAsync([FromRoute]Guid id, [FromForm] SampleDto dto)
        {
           Console.WriteLine(dto.Text); //Return null
           Console.WriteLine(dto.Image[0]?.FileName); //Return null

            return Ok();
        }

Here is the value of my Form

Here is what the browser send:

Here is the code generated by nswag:

```
update(id: string, dto: SampleDto | null | undefined): Observable {
let url_ = this.baseUrl + "/api/v1/Sample/{id}";
if (id === undefined || id === null)
throw new Error("The parameter 'id' must be defined.");
url_ = url_.replace("{id}", encodeURIComponent("" + id));
url_ = url_.replace(/[?&]$/, "");

    const content_ = new FormData();
    if (dto !== null && dto !== undefined)
        content_.append("dto", dto.toString());

    let options_ : any = {
        body: content_,
        observe: "response",
        responseType: "blob",
        headers: new HttpHeaders({
            "Accept": "application/json"
        })
    };

    return _observableFrom(this.transformOptions(options_)).pipe(_observableMergeMap(transformedOptions_ => {
        return this.http.request("put", url_, transformedOptions_);
    })).pipe(_observableMergeMap((response_: any) => {
        return this.transformResult(url_, response_, (r) => this.processUpdate(<any>r));
    })).pipe(_observableCatch((response_: any) => {
        if (response_ instanceof HttpResponseBase) {
            try {
                return this.transformResult(url_, response_, (r) => this.processUpdate(<any>r));
            } catch (e) {
                return <Observable<SampleDto | null>><any>_observableThrow(e);
            }
        } else
            return <Observable<SampleDto | null>><any>_observableThrow(response_);
    }));
}

```

Here there is a repo where it s possible to upload data and File: https://github.com/fiyazbinhasan/AngularSpaCore

In Swagger, the array of IFormFile seems to be manage correctly now:

[zuckerthoben]

I have the same problem as @barmyard. With ApiExplorer my Upload Actions are not detected correctly. Any updates?

[MennoVisser91]

I have the same problem. Any updates???

[JonasDev99]

This is actually a swagger-ui issue. Go vote for it by giving a thumbs up: https://github.com/swagger-api/swagger-ui/issues/4600

[RicoSuter]

So the generated spec is correct and we have to wait for a swagger ui update?

[Fedorus]

I`m shoked that this bug is still exist,,,

[JonasDev99]

So the generated spec is correct and we have to wait for a swagger ui update?

I think so, yes...

[Juice-XIJ]

Hi @RicoSuter at this moment the swagger issue just fixed a few days ago.

I updated NSwag to 13.6.0. Now the generated swagger.json looks like:

"requestBody": {
    "content": {
        "multipart/form-data": {
            "schema": {
                "type": "object",
                "properties": {
                    "audioFileList": {
                        "type": "array",
                        "items": {
                            "type": "string",
                            "format": "binary"
                        }
                    }
                }
            }
        }
    }
}

This schema is the same as latest swagger client. However when I use the swagger ui to send request to the sever, I found that the request is like:

Host: localhost:8446
Connection: keep-alive
Content-Length: 157
accept: application/json
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.61 Safari/537.36 Edg/83.0.478.37
Ocp-Apim-Subscription-Key: 5b9e48e85daf4c32aab4d403d0eea5cd
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryplFirfy6HmAbgpAl
Origin: https://localhost:8446
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: cors
Sec-Fetch-Dest: empty
Referer: https://localhost:8446/UI/index.html?urls.primaryName=OpenApi%203.0
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.9
Cookie: ai_user=I8/5h|2020-04-18T00:44:53.179Z; grafana_session=348d3dc50bd60b4c0045046d35440dc9

------WebKitFormBoundaryplFirfy6HmAbgpAl
Content-Disposition: form-data; name="audioFileList"

[object File]
------WebKitFormBoundaryplFirfy6HmAbgpAl--

The request only sent string '[object file]" instead of the form data that I selected (also, content length is only 157).

Hence, any thoughts about it? Thanks!

[dmitry-pavlov]

I confirm that:

• Swagger UI 3 sends files array as [object File] <-- which makes ASP.NET Core request.Form.Files getting no files on controller side.

curl -X POST "http://localhost:5000/api/attachments" -H "accept: application/json" -H "Authorization: Bearer eyJ...trimmed..." 
-H "Content-Type: multipart/form-data" -F "StructureId=14" -F "Description=dsgf" -F "Files=[object File]" 

• Open API schema looks good and generates correct TypeScript code (the only thing I had to adjust was mapping form files to to objects of FileParameter - code snippet is below as well) which works fine.

"/api/attachments": {
      "post": {
        "tags": [           "Attachments"         ],
        "operationId": "Attachments_AttachStructureFile",
        "requestBody": {
          "content": {
            "multipart/form-data": {
              "schema": {
                "type": "object",
                "properties": {
                  "StructureId": {                     "type": "integer",                    "format": "int32"                  },
                  "Description": {                    "type": "string",                    "nullable": true                  },
                  "Files": {
                    "type": "array",
                    "nullable": true,
                    "items": {
                      "type": "string",
                      "format": "binary"
                    }
                  },
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "", 
            "content": {
              "application/json": {
                "schema": {                  "$ref": "#/components/schemas/SipAttachStructureFileResponse"                }
              }
            }
          }
        },
        "security": [          {            "JWT": []          }        ]
      }
    }

What I use:

• NSwag.AspNetCore v 13.7.0 (package in API project which is used to generate OpenAPI spec for Swagger UI 3)
• NSwagStudio (x64) 13.7.0.0 (this what I use to generate TS client)

So it's fine except using Swagger UI 3 for uploading files. Any workarounds how to make Swagger UI sending correct data?

[RicoSuter]

Do we need to update Swagger UI 3 in NSwag.AspNetCore?
Didnt do that for some months so maybe there are already improvements.