@Schema(types = "xxx") does not work for multipart param with enabled springdoc.default-support-form-data config option

[kkochanski]

I'm using.

• Spring Boot v3.4.1
• Springdoc OpenAPI v2.8.1
• OAS v3.1

In my example I'm using @Schema(types = "boolean").

Here's a code that will generate a valid Swagger definition.

@PostMapping(path = "/dummy", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
@ResponseStatus(value = HttpStatus.OK)
public String dummy(
    @RequestPart(value = "file", required = false) MultipartFile file,
    @Parameter(description = "There is dummy param", schema = @Schema(types = "boolean")) @RequestParam(name = "is_dummy") String isDummy
) {
    return "";
}

The param definition is as follows. It's valid.

"parameters": [
    {
        "name": "is_dummy",
        "in": "query",
        "description": "There is dummy param",
        "required": true,
        "schema": {
            "type": "boolean"
        }
    }
],
"requestBody": {
    "content": {
        "multipart/form-data": {
            "schema": {
                "type": "object",
                "properties": {
                    "file": {
                        "type": "string",
                        "format": "binary"
                    }
                }
            }
        }
    }
}

Then let's try to set true for springdoc.default-support-form-data config option. We will get a param definition as follows.

"requestBody": {
    "content": {
        "multipart/form-data": {
            "schema": {
                "type": "object",
                "properties": {
                    "file": {
                        "type": "string",
                        "format": "binary"
                    },
                    "is_dummy": {
                        "description": "There is dummy param"
                    }
                }
            }
        }
    }
}

The schema to is_dummy field is not added anymore.

Another example properly working example. Code below. POST with application/x-www-form-urlencoded content type.

@PostMapping(path = "/dummy", consumes = MediaType.APPLICATION_FORM_URLENCODED_VALUE)
    @ResponseStatus(value = HttpStatus.OK)
    public String dummy(
        @Parameter(description = "There is dummy param", schema = @Schema(types = "boolean")) @RequestParam(name = "is_dummy") String isDummy
    ) {
        return "";
    }

It produces valid param definition.

"requestBody": {
    "content": {
        "application/x-www-form-urlencoded": {
            "schema": {
                "type": "boolean",
                "description": "There is dummy param"
            }
        }
    }
},