Adding support for multipart/form-data

[judepereira]

We need to facilitate the movement of data using the Content-Type multipart/form-data.

Spec update

actions:
  my_action:
    http:
      contentType: multipart/form-data
    arguments:
      my_argument:
        in: formBody

What this adds support for

1. Support for making requests with the content type set to multipart/form-data
   1. Each argument will be sent as a form field

[wilzbach]

AFAICT the spec doesn't allow binary data as of now, so I think we first should add this to the spec before.

actions:
  my_action:
    http:
      contentType: multipart/form-data
    arguments:
      my_file:
        in: formBody
        contentType: binary OR image/jpeg # <- this is missing

See e.g.

• https://tools.ietf.org/html/rfc2183
• https://swagger.io/docs/specification/describing-request-body/file-upload/

[judepereira]

@wilzbach - according to this, it should be as follows:

arguments:
  my_file:
    in: formBody
    type: object
    contentType: */*

This is already supported in output, we can add it to the argument as well.