Quickly open shell access to a running docker container. Usage: dockr [container name].

dockr

#!/usr/bin/env bash

base_command="docker exec -it"
shells=(/bin/bash /bin/ash /bin/sh)

if [[ $1 == "" ]]
then
  printf "Usage: dockr [container name]\n"
  exit 1
fi

for shell in ${shells[@]}
do
  printf "Trying $shell..."
  if docker exec $1 [ -f $shell ]
  then
    printf "ok\n"
    $base_command $1 $shell
    break
  fi
  printf "not found.\n"
done

Also see the accompanying Bash completion script here: https://gist.github.com/Dullage/09905072df9f948f61cad10e9d8183c6