Warning: mysqli::__construct(): (HY000/2002): Input/output error in /workspace/class/CsBuilder.php on line 209

Fatal error: Uncaught Error: Call to a member function real_escape_string() on integer in /workspace/class/CsBuilder.php:720
Stack trace:
#0 /workspace/class/CsBuilder.php(744): CsBuilder->processAppSlug()
#1 /workspace/class/CsBuilder.php(4968): CsBuilder->checkAppSlug()
#2 /workspace/config.php(85): CsBuilder->initialiseBuilder(Array)
#3 /workspace/index.php(83): require('/workspace/conf...')
#4 {main}
  thrown in /workspace/class/CsBuilder.php on line 720