[IMPALA-2110] readline bug in centos 7 causes the Impala shell to produce garbled output when used in non-interactive mode.

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Impala 2.2
• Fix Version/s: Impala 2.3.0
• Component/s: Clients
• Labels: shell
• Environment: Centos 7
• Target Version: Impala 2.3.0
• Assignee: Ishaan Joshi
• Reporter: Ishaan Joshi
• Created: 01/Jul/15 01:14
• Updated: 28/Dec/15 17:43
• Resolved: 04/Sep/15 22:39

Description

According to https://bugs.python.org/issue19884, the default readline that gets packaged with centos 7 causes a bunch of escape characters to appear in the impala-shell output. This is quite bad for scripting against the shell in non-interactive mode.

There are a bunch of ways to solve this, for e.g: http://stackoverflow.com/questions/15760712/python-readline-module-prints-escape-character-during-import

I think the simplest way to fix it is to set TERM to a dummy value instead of xterm-256 for the shell sub process when it's used in non-interactive mode.