Today, I had to read a binary file and transmit it over HTTP post. Here is what I did, which worked perfectly on my localhost (?) but had wierdness all over it on Heroku/Production.

contents = open("#{Rails.root}/tmp/#{fname}.data", "rb") {|io| io.read }
HTTParty.post("#{params["url"]}", {:body => contents, :headers => {'Content-Type' => 'avro/binary',  'Authorization' => params["token"]}})

On the other end, I was dumping this binary data into a file for post processing. In development, this worked fine. However, in production, I was getting a wierd error when I tried to read the data from the binary file. The error was something along the lines of -

ArgumentError ("negative length" -

After much digging, I traced it down to an encoding issue because the data was getting modified someway during the POST operation. The right way to do this is to encode the data using Base64.

contents = open("#{Rails.root}/tmp/#{fname}.data", "rb") {|io| Base64.encode64(io.read) }
HTTParty.post("#{params["url"]}", {:body => contents, :headers => {'Content-Type' => 'avro/binary',  'Authorization' => params["token"]}})

This preserves the data. This makes sense. I still am not sure, why it was working on my localhost.