Bash function for opening a bash inside a Docker container specifying the image name instead of the id

dockerbash.md

dockerbash

Why?

When working on a Dockerfile I often need to open a bash inside the generated container in order to check what the Dockerfile has generated.

This requires 3 steps:

• running docker ps
• checking the container id that we need (usually based on the image name)
• running docker exec -i -t <container_id> bash

This script does this in one step: dockerbash <image_name>

How to use

Put in on a directory and load it from your ~/.bashrc

source ~/bash_functions/dockerbash.sh

dockerbash.sh

function dockerbash() {

    if [ "$#" -ne 1 ]; then
        echo "Usage: dockerbash <image_name>"
        return 1
    fi
    
    running=`docker ps | grep "$1"`
    number=`echo "$running" | wc -l`

    if [ -z "$running" ]; then
        echo "No container found for $1"
        return 1
    elif [ "$number" -eq 1 ]; then
        id=`echo $running | cut -d" " -f1`
    else
        echo "Multiple containers found, please specify the id"
        echo "$running"
        echo -n "Id: "
        read id
    fi
    
    docker exec -i -t $id bash
}