Params extension does not work when param_type is body

[lenon]

Hi!

When I try to document an extension for a parameter like this:

requires :foo, type: String, documentation: { x: { some: 'stuff' }, param_type: 'body' }

It does not work. The documentation is generated without the x-some extension.

But when param_type is omitted:

requires :foo, type: String, documentation: { x: { some: 'stuff' } }

The generated documentation includes the x-some extension.

I wrote the following script to help reproduce this problem:

require 'grape'
require 'grape-swagger'

class API < Grape::API
  format :json

  params do
    requires :foo, type: String, documentation: { x: { some: 'stuff' } }
  end
  post :test1 do
  end

  params do
    requires :foo, type: String, documentation: { x: { some: 'stuff' }, param_type: 'body' }
  end
  post :test2 do
  end

  add_swagger_documentation
end

This is the generated documentation:

(I redacted it to keep only the relevant content)

{
    ...
    "paths": {
        "/test1": {
            "post": {
                ...
                "parameters": [
                    {
                        "in": "formData",
                        "name": "foo",
                        "type": "string",
                        "required": true,
                        "x-some": "stuff"
                    }
                ],
                ...
            }
        },
        "/test2": {
            "post": {
                ...
                "parameters": [
                    {
                        "name": "postTest2",
                        "in": "body",
                        "required": true,
                        "schema": {
                            "$ref": "#/definitions/postTest2"
                        }
                    }
                ],
                ...
            }
        }
    },
    "definitions": {
        "postTest2": {
            "type": "object",
            "properties": {
                "foo": {
                    "type": "string"
                }
            },
            "required": [
                "foo"
            ]
        }
    }
}

As you can see in the JSON, when in is formData, "x-some": "stuff" is present. When in is body, it isn't.

I think this happens because of this method in the MoveParams class, which appears to be used to document body params:

grape-swagger/lib/grape-swagger/doc_methods/move_params.rb

Lines 104 to 115 in 3a5da56

	def document_as_property(param)
	property_keys.each_with_object({}) do |x, memo|
	next unless param.key?(x)
	value = param[x]
	if x == :type && @definitions[value].present?
	memo['$ref'] = "#/definitions/#{value}"
	else
	memo[x] = value
	end
	end
	end

It uses a fixed list of properties from property_keys and documents them if they are present. Anything else that is not in this list gets discarded.

Maybe it would be possible to change this method to check for keys that start with x- and document them.

Does that make sense? I can try to make a PR if it does.

Thanks!

[LeFnord]

Hi @lenon … thanks for the detailed bug report, and yes I PR would be very welcome … 👍

[lenon]

Fixed by #918. Thanks @numbata 😃