NameError: uninitialized constant Rack::RACK_VERSION

[deepj]

When I run the following script:

run lambda {|env| [200, {}, ["Hello World"]]}

using

NIO4R_PURE=true falcon --verbose serve -c falcon.rb --threaded

Note: use it for testing falcon under Trufferuby

I got this issue under Ruby 2.5.3/Truffleruby 1.0.0-rc9 on macOS 10.14

D, [2018-11-06T20:52:24.014304 #38164] DEBUG -- Async::IO::Socket: Binding to #<Addrinfo: [::1]:9292 TCP (localhost)>
D, [2018-11-06T20:52:24.014689 #38164] DEBUG -- Async::IO::Socket: Binding to #<Addrinfo: 127.0.0.1:9292 TCP (localhost)>
D, [2018-11-06T20:52:24.014840 #38164] DEBUG -- <Async::Reactor:0x3fbf92cf4770 stopped=false>: Exiting run-loop because finished.
I, [2018-11-06T20:52:24.014951 #38164]  INFO -- : Falcon taking flight! Binding to #<Falcon::Endpoint https://localhost:9292/ {}> [Async::Container::Threaded with concurrency: 4]
I, [2018-11-06T20:52:24.015345 #38164]  INFO -- : Send `kill -USR1 38164` for detailed status :)
I, [2018-11-06T20:52:24.016304 #38164]  INFO -- : Send `kill -USR1 38164` for detailed status :)
I, [2018-11-06T20:52:24.015543 #38164]  INFO -- : Send `kill -USR1 38164` for detailed status :)
I, [2018-11-06T20:52:24.017282 #38164]  INFO -- : Send `kill -USR1 38164` for detailed status :)
E, [2018-11-06T20:52:33.333196 #38164] ERROR -- #<Async::IO::SSLServer:0x00007f7f259c8d20>: SSL_accept returned=1 errno=0 state=unknown state: sslv3 alert bad certificate (OpenSSL::SSL::SSLError)
~/.gem/ruby/2.5.3/gems/async-io-1.16.3/lib/async/io/generic.rb:128:in `accept_nonblock'
~/.gem/ruby/2.5.3/gems/async-io-1.16.3/lib/async/io/generic.rb:128:in `async_send'
~/.gem/ruby/2.5.3/gems/async-io-1.16.3/lib/async/io/generic.rb:47:in `block in wrap_blocking_method'
~/.gem/ruby/2.5.3/gems/async-io-1.16.3/lib/async/io/ssl_socket.rb:126:in `block in accept'
~/.gem/ruby/2.5.3/gems/async-1.10.3/lib/async/task.rb:74:in `block in initialize'
D, [2018-11-06T20:52:48.613432 #38164] DEBUG -- Async::HTTP::Protocol::HTTPS: Negotiating protocol "h2"...
D, [2018-11-06T20:52:48.615964 #38164] DEBUG -- #<Falcon::Server:0x00007f7f259c8e88>: Incoming connnection from #<Addrinfo: [::1]:50229 TCP> to #<Async::HTTP::Protocol::HTTP2::Server:0x00007f7f259aba18>
D, [2018-11-06T20:52:48.616093 #38164] DEBUG -- localhost:9292: GET / HTTP/2.0 from #<Addrinfo: [::1]:50229 TCP>
E, [2018-11-06T20:52:48.618435 #38164] ERROR -- : NameError: uninitialized constant Rack::RACK_VERSION
Did you mean?  RUBY_VERSION
	~/.gem/ruby/2.5.3/gems/falcon-0.19.2/lib/falcon/adapters/rack.rb:92:in `call'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/middleware.rb:57:in `call'
	~/.gem/ruby/2.5.3/gems/falcon-0.19.2/lib/falcon/adapters/rewindable.rb:61:in `call'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/middleware.rb:57:in `call'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/content_encoding.rb:44:in `call'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/middleware.rb:57:in `call'
	~/.gem/ruby/2.5.3/gems/falcon-0.19.2/lib/falcon/verbose.rb:50:in `call'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/middleware.rb:57:in `call'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/server.rb:63:in `block in accept'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/protocol/http2/server.rb:63:in `each'
	~/.gem/ruby/2.5.3/gems/async-http-0.37.0/lib/async/http/server.rb:52:in `accept'
	~/.gem/ruby/2.5.3/gems/async-io-1.16.3/lib/async/io/socket.rb:68:in `block in accept_each'
	~/.gem/ruby/2.5.3/gems/async-io-1.16.3/lib/async/io/ssl_socket.rb:128:in `block in accept'
	~/.gem/ruby/2.5.3/gems/async-1.10.3/lib/async/task.rb:74:in `block in initialize'

I used Firefox to open the "page".

[ioquatix]

It should be referring to these constants and more...

https://github.com/rack/rack/blob/7eebdd63ab3e7f890a13eb127ccf28cc31d7d505/lib/rack.rb#L63

I wonder why it's not loading them.

[ioquatix]

Okay, I could reproduce the issue... hold on.

[deepj]

The above code fails with newest 0.19.3 on this error

falcon/adapters/rack.rb:40:in `initialize': App must be callable! (ArgumentError)

^^ @ioquatix

[ioquatix]

Yeah, don't use -c falcon.rb because it actually tries to load lib/falcon/falcon.rb which returns a module. I don't know why it's doing that, but it's somewhere in the guts of rack. Please ensure you use config.ru for now.

[ioquatix]

I added that argument error because I ran into that and I wanted it to fail during construction not use.

[deepj]

@ioquatix thx for the explanation and the help. I can run it under truffleruby. Unfortunately, when I want to open the page, it fails on something Truffleruby internal error :) I'm going to report it.

[ioquatix]

Okay, I found out why it has funny behaviour.

https://github.com/rack/rack/blob/master/lib/rack/builder.rb#L36-L51

If you do Rack::Builder.parse_file('falcon.rb') it executes require 'falcon.rb' and returns Object.const_get('Falcon'). Wow. That's surprising.