Documentation no longer include JSON response body when using with Rack >= 2.1.0

[sikachu]

Hello,

This issue is pretty much for reporting the incompatibility to the gem author, and hopefully it will help anyone who runs into this problem to understand what's going on.

Basically, after we upgrade our dependencies to use Rack 2.1.1, we noticed that our generated documentation no longer show JSON response but instead showing [binary data] instead.

Digging in further, we found out that in rack/rack@8c62821, especially this change, MockResponse#body now creates a buffer and use << to join the content together. However, on line 195, the author uses String.new without specifying the encoding, resulting in Ruby creating a new String with ASCII-8BIT encoding by default.

As it turns out, rspec_api_documentation relies on string encoding to determine if it should include the response body in the documentation or not:

rspec_api_documentation/lib/rspec_api_documentation/client_base.rb

Lines 90 to 95 in 560c3bd

	if response_body.encoding == Encoding::ASCII_8BIT
	"[binary data]"
	else
	formatter = RspecApiDocumentation.configuration.response_body_formatter
	return formatter.call(response_content_type, response_body)
	end

Hence, the change in Rack broke this conditional.

I've reported this issue to Rack in rack/rack#1486, and hopefully we can solve this soon.

The solution right now for us is to lock Rack to ~> 2.0.8 for now.

Thank you very much.

[FrankFang]

Any other workaround?

[Tao-Galasse]

I ran into the same issue recently. I don't really like this solution, but I fixed it using mokey patching:
config/initializers/rspec_api_documentation.rb

module RspecApiDocumentation
  class RackTestClient < ClientBase
    def response_body
      last_response.body.encode("utf-8")
    end
  end
end

Indeed, it seems to be caused by an encoding issue where utf-8 become ascii-8bit

[eimermusic]

This seems to also be the result after Rails 6 upgrade.

[bitlather]

Just created a new rails 6 app and had this problem, Tao's response above fixed it (#456 (comment))

[cpursley]

Tao-Galasse's solution worked but I found that I needed to stick it right before the RspecApiDocumentation.configure block instead of the initializers directory.

[skibox]

There's an additional issue with endpoints that use send_data:

     Failure/Error: last_response.body.encode("utf-8")
     
     Encoding::UndefinedConversionError:
       "\xD3" from ASCII-8BIT to UTF-8
     # ./config/initializers/rspec_api_documentation.rb:6:in `encode'
     # ./config/initializers/rspec_api_documentation.rb:6:in `response_body'

I've tweaked Tao's fix, it ain't perfect but it works for my projects:

module RspecApiDocumentation
  class RackTestClient < ClientBase
    def response_body
      if last_response.headers["Content-Type"].include?("json")
        last_response.body.encode("utf-8")
      else
        "[binary data]"
      end
    end
  end
end

[ShamoX]

On my side, I fixed it by two mechanisms :

1. @skibox's @Tao-Galasse solution remade mine
2. Use response_body_formatter like it is intended to filter the different kind of output and make it OK for apitome

Resulting in this spec/support/rspec_api_documentation.rb file :

# frozen_string_literal: true

# Fix a bug that generate erroneous "[binary data]" not yet fixed on rspec_api_documentation:6.1.0
module RspecApiDocumentation
  class RackTestClient < ClientBase
    def response_body
      body = last_response.body
      if body.empty? || last_response.headers['Content-Type'].include?('json')
        body.encode('utf-8')
      else
        '"[binary data]"'
      end
    rescue Encoding::UndefinedConversionError
      '"[binary data]"'
    end
  end
end

# configure rspec_api_documentation
RspecApiDocumentation.configure do |config|
# ..... some unrelated config here  

  # Change how the response body is formatted by default
  # Is proc that will be called with the response_content_type & response_body
  # by default response_content_type of `application/json` are pretty formated.
  config.response_body_formatter = lambda do |response_content_type, response_body|
    if response_content_type.include?('application/json')
      JSON.parse(response_body)
      return response_body
    elsif response_content_type.include?('text') || response_content_type.include?('txt')
      # quote it for JSON Parser in documentation reader like APITOME
      return "\"#{response_body}\""
    else
      return '"[binary data]"'
    end
  rescue JSON::ParseError
    '"[binary data]"'
  end

# ... Other unrelated config
end

[davidstosik]

Just to make sure people notice, this issue would be fixed by #458 🙇‍♂️

[jakehow]

For anyone following this, Ive merged #458 please let me know if this resolves the issue for you. cc @artofhuman