Add support for 'multipart/form-data' file upload

[jpaulgs]

I'm attempting to describe file upload, according to swagger docs for file-upload we should define the file as type string with the format of binary.

so my openapi for this request looks like:

      requestBody:
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                contractId:
                  type: string
                  example: 270A2087-6335-455E-B32D-350C00FFEEB7
                organisationId:
                  description: Your ID for this participant
                  example: AAA123
                  type: string
                resourceId:
                  type: string
                  example: 49E2797A-A62E-4042-9587-2CC0A1DBC679
                file:
                  type: string
                  format: binary

However by the time this gets to the committee middleware rack has exploded the file to a hash

file: {
  :filename=>"i_am_a_file.csv", 
  :type=>"text/plain", 
  :name=>"file", 
  :tempfile=>#<Tempfile:/tmp/RackMultipart20200306-13-1rx39tl.csv>, 
  :head=>"Content-Disposition: form-data; name=\"file\"; filename=\"i_am_a_file.csv\"\r\nContent-Type: text/plain\r\nContent-Length: 81\r\n"
}

so we end up with an error like:

#/paths/~1api~1v1~1telemetry_data_files/post/requestBody/content/multipart~1form-data/schema/properties/file expected string, but received Hash:

I was looking at test/request_unpacker_test.rb but I do not see how to handle this situation. What am I missing?

[masayuki14]

I faced to same problem too.
I solved problem as to use monky patch like follows.
This is not a sufficient change. But the test can pass.

module StringValidatorPatch
  def coerce_and_validate(value, schema, **_keyword_args)
    # change this
    # https://github.com/ota42y/openapi_parser/blob/61874f0190a86c09bdfb78de5f51cfb6ae16068b/lib/openapi_parser/schema_validators/string_validator.rb#L11
    unless value.is_a?(String)
      return OpenAPIParser::ValidateError.build_error_result(value, schema) if schema.format != 'binary'
    end
    # --- end

    value, err = check_enum_include(value, schema)
    return [nil, err] if err

    value, err = pattern_validate(value, schema)
    return [nil, err] if err

    unless @datetime_coerce_class.nil?
      value, err = coerce_date_time(value, schema)
      return [nil, err] if err
    end

    value, err = validate_max_min_length(value, schema)
    return [nil, err] if err

    value, err = validate_email_format(value, schema)
    return [nil, err] if err

    value, err = validate_uuid_format(value, schema)
    return [nil, err] if err

    [value, nil]
  end
end

class OpenAPIParser::SchemaValidator::StringValidator
  prepend StringValidatorPatch
end

[pechorin]

The actual version of patch (maybe, not sure, but works for my test suite):

module StringValidatorPatch
  def coerce_and_validate(value, schema, **_keyword_args)
    # Diff:
    # :- return OpenAPIParser::ValidateError.build_error_result(value, schema) unless value.kind_of?(String)
    #
    # :+
    if !value.is_a?(String)
      if schema.format == 'binary'
        # Fix: in tests rack uploaded file not converts automatically (committee bug)
        if value[:tempfile]
          return [ActionDispatch::Http::UploadedFile.new(value), nil]
        else
          return [value, nil]
        end
      else
        return OpenAPIParser::ValidateError.build_error_result(value, schema)
      end
    end
    # End of diff

    value, err = check_enum_include(value, schema)
    return [nil, err] if err

    value, err = pattern_validate(value, schema)
    return [nil, err] if err

    value, err = validate_max_min_length(value, schema)
    return [nil, err] if err

    value, err = validate_email_format(value, schema)
    return [nil, err] if err

    value, err = validate_uuid_format(value, schema)
    return [nil, err] if err

    value, err = validate_date_format(value, schema)
    return [nil, err] if err

    value, err = validate_datetime_format(value, schema)
    return [nil, err] if err

    [value, nil]
  end
end

class OpenAPIParser::SchemaValidator::StringValidator
  prepend StringValidatorPatch
end

[ota42y]

We have no plans to fix it at this time (not that we don't want to, just that we don't have time to deal with it).
However, if there is an error, we would like to have some workaround (no verification, but no error either).