ruby on rails - Puma: HTTP parse error, malformed request -

firing local server foreman , following whenever make request.

http parse error, malformed request (): #<puma::httpparsererror: invalid http format, parsing fails.> env: {"rack.version"=>[1, 3], "rack.errors"=>#<io:<stderr>>, "rack.multithread"=>true, "rack.multiprocess"=>false, "rack.run_once"=>false, "script_name"=>"", "content_type"=>"text/plain", "query_string"=>"", "server_protocol"=>"http/1.1", "server_software"=>"2.9.1", "gateway_interface"=>"cgi/1.2"} 

running ruby 2.2.0 rvm

and potentially relevant bits gemfile:

gem 'rails', '4.2.5.2' gem 'puma', '2.9.1' 

completely stumped here , appreciate help. happy provide more context config, don't know start.

edit:

i error when run server foreman start. if fire rails s well.

not sure if found cause of one, underlining issue seems '%' characters in url.

i tried upgrading latest version of puma '3.4.0' still able reproduce error.

hopefully helps replicate issue. update when find fix.