This repo is designed to reproduce an issue with mysql2 gem outlined here: brianmario/mysql2#571

The issue is connected to proxying TCP traffic through a SOCKS5 proxy using the Dante socksify client. This client only support Linux so this test will not work on Windows or OSX.

It uses a test MySQL DB running Mysql 5.6.19a and an open SOCKS5 proxy running Dante 1.4 server.

Suggested Reproduction steps

1. Install dependencies

This should install the latest version of mysql2 & bundler should pull down the last working version 0.3.15

git clone [email protected]:timrwilliams/socks-mysql2-debug.git
gem install mysql2
bundle install

2. Test connectivity

a) mysql2 v0.3.17 with no proxy - WORKS

ruby connectivity.rb
  ======== OUTPUT ==========
  mysql2 version: 0.3.17
  {"1+2"=>3}

b) mysql2 v0.3.15 with proxy - WORKS

./socksify bundle exec ruby connectivity.rb 
  Proxying requests via SOCKS5
  ======== OUTPUT ==========
  mysql2 version: 0.3.15
  {"1+2"=>3}

c) mysql2 v0.3.17 with proxy - FAILS

./socksify ruby connectivity.rb 
  Proxying requests via SOCKS5
  ======== OUTPUT ==========
  mysql2 version: 0.3.17
  ...Hangs indefinitely...

Test c generates between 5 - 10 failed connection attempts per seconds resulting in mysql blocking the requesting host. Please contact me to flush the mysql hosts if you're trying to debug the issue and trigger this.