Ruby on rails HTTP parse error, malformed request (): #<Puma::HttpParserError: Invalid HTTP format, parsing fails

Question

I am implementing a site where i will use omniauth-facebook with devise gem. I have followed all the instructions from this link https://github.com/rails-camp/facebook-omniauth-demo and also finished set up facebook app.Every time I am getting this error from the browser "This site can’t provide a secure connection". From the rails console what I can see is:

HTTP parse error, malformed request (): #<Puma::HttpParserError: Invalid HTTP format, parsing fails.>

Are there any solution?