I have a problem with OpenAPI curl generation.

I have to create POST method with three parameters: application/json, text/plain and multipart/form-data medium types. So curl that is going to be generated by OpenAPI is supposed to be like:

curl -X 'POST' \
  'http://localhost:8080/test/third' \
  -H 'accept: */*' \
  -H 'Content-Type: multipart/form-data' \
  -F 'file=@test_file.docx;type=multipart/form-data' \
  -F 'dto={"name":"string","description":"string"};type=application/json' \
  -F 'str=some_test_value;type=text/plain' \

But it doesn't work.

Controller:

package .example.springbased.web;

import io.swagger.v3.oas.annotations.Parameter;
import io.swagger.v3.oas.annotations.media.Content;
import io.swagger.v3.oas.annotations.media.Encoding;
import io.swagger.v3.oas.annotations.parameters.RequestBody;
import .springframework.http.MediaType;
import .springframework.http.ResponseEntity;
import .springframework.web.bind.annotation.PostMapping;
import .springframework.web.bind.annotation.RequestMapping;
import .springframework.web.bind.annotation.RequestPart;
import .springframework.web.bind.annotation.RestController;
import .springframework.web.multipart.MultipartFile;

@RestController
@RequestMapping("/test")
public class TestController {

    @PostMapping(value = "/second", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
    public ResponseEntity<String> test(
        @RequestBody(content = @Content(encoding = @Encoding(name = "dto", contentType = MediaType.APPLICATION_JSON_VALUE)))
        @Parameter(description = "An extra JSON payload sent with file")
        @RequestPart("dto")
        DTO dto,
        @RequestBody(content = @Content(encoding = @Encoding(name = "file", contentType = MediaType.MULTIPART_FORM_DATA_VALUE)))
        @Parameter(required = true)
        @RequestPart("file") MultipartFile file){
        return ResponseEntity.ok("Request Accepted: " + dto.toString());
    }

    @PostMapping(value ="/first", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
    public ResponseEntity<String> uploadMultipartWithBody(
        @RequestBody(content = @Content(encoding = @Encoding(name = "file", contentType = MediaType.MULTIPART_FORM_DATA_VALUE)))
        @Parameter(required = true)
        @RequestPart("file") MultipartFile file,
        @RequestBody(content = @Content(encoding = @Encoding(name = "dto", contentType = MediaType.APPLICATION_JSON_VALUE)))
        @Parameter(description = "An extra JSON payload sent with file")
        @RequestPart("dto")
        DTO dto){
        return ResponseEntity.ok("Request Accepted: " + dto.toString());
    }

    @PostMapping(value ="/third", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
    public ResponseEntity<String> threeParams(
        @RequestBody(content = @Content(encoding = @Encoding(name = "file", contentType = MediaType.MULTIPART_FORM_DATA_VALUE)))
        @Parameter(required = true)
        @RequestPart("file") MultipartFile file,
        @RequestBody(content = @Content(encoding = @Encoding(name = "dto", contentType = MediaType.APPLICATION_JSON_VALUE)))
        @Parameter(description = "An extra JSON payload sent with file")
        @RequestPart("dto")
        DTO dto,
        @RequestBody(content = @Content(encoding = @Encoding(name = "str", contentType = MediaType.TEXT_PLAIN_VALUE)))
        @RequestPart("str")
        String str){
        return ResponseEntity.ok("Request Accepted: " + dto.toString());
    }
}

Generated OpenAPI:

{
  "openapi": "3.1.0",
  "info": {
    "title": "OpenAPI definition",
    "version": "v0"
  },
  "servers": [
    {
      "url": "http://localhost:8080",
      "description": "Generated server url"
    }
  ],
  "paths": {
    "/test/third": {
      "post": {
        "tags": [
          "test-controller"
        ],
        "operationId": "threeParams",
        "requestBody": {
          "content": {
            "multipart/form-data": {
              "schema": {
                "type": "object",
                "properties": {
                  "file": {
                    "type": "string",
                    "format": "binary"
                  },
                  "dto": {
                    "$ref": "#/components/schemas/DTO"
                  },
                  "str": {
                    "type": "string"
                  }
                },
                "required": [
                  "dto",
                  "file",
                  "str"
                ]
              },
              "encoding": {
                "file": {
                  "contentType": "multipart/form-data"
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "OK",
            "content": {
              "*/*": {
                "schema": {
                  "type": "string"
                }
              }
            }
          }
        }
      }
    },
    "/test/second": {
      "post": {
        "tags": [
          "test-controller"
        ],
        "operationId": "test",
        "requestBody": {
          "content": {
            "multipart/form-data": {
              "schema": {
                "type": "object",
                "properties": {
                  "dto": {
                    "$ref": "#/components/schemas/DTO"
                  },
                  "file": {
                    "type": "string",
                    "format": "binary"
                  }
                },
                "required": [
                  "dto",
                  "file"
                ]
              },
              "encoding": {
                "dto": {
                  "contentType": "application/json"
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "OK",
            "content": {
              "*/*": {
                "schema": {
                  "type": "string"
                }
              }
            }
          }
        }
      }
    },
    "/test/first": {
      "post": {
        "tags": [
          "test-controller"
        ],
        "operationId": "uploadMultipartWithBody",
        "requestBody": {
          "content": {
            "multipart/form-data": {
              "schema": {
                "type": "object",
                "properties": {
                  "file": {
                    "type": "string",
                    "format": "binary"
                  },
                  "dto": {
                    "$ref": "#/components/schemas/DTO"
                  }
                },
                "required": [
                  "dto",
                  "file"
                ]
              },
              "encoding": {
                "file": {
                  "contentType": "multipart/form-data"
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "OK",
            "content": {
              "*/*": {
                "schema": {
                  "type": "string"
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "DTO": {
        "type": "object",
        "description": "An extra JSON payload sent with file",
        "properties": {
          "name": {
            "type": "string"
          },
          "description": {
            "type": "string"
          }
        }
      }
    }
  }
}

As you can see even if I specify

@RequestBody(content = @Content(encoding = @Encoding(name = "...", contentType = MediaType....))

for each parameter it takes only the first one that's specified for the first parameter.

Why? What I need to do to make it works?

Dependencies that I use with gradle + java 21:

dependencies {
    implementation '.springframework.boot:spring-boot-starter-web'
    implementation '.springdoc:springdoc-openapi-starter-webmvc-ui:2.8.6'
    implementation '.springframework.boot:spring-boot-devtools'
}

Documentation that I followed: