Running shell script from PC in running Docker

Question

I have pulled one docker image and docker container is running successfully as well. But I want to run one shell script in the running docker. The shell script is located in my hard disk. I am unable to find out which command to use and how to give pathname of the shell file so that it can be executed in running docker.

Please guide me.

Regards

Answer 1

TL;DR

There are two ways that could work in your case.

1. You can run one-liner-script using docker exec sh/bash with -c argument:

docker exec -i <your_container_id> sh -c 'sh-command-1 && sh-command-2 && sh-command-n'

2. You can copy shell script into container using docker cp and then run it in docker context:

docker cp ~/your-shell-script.sh <your_container_id>:/tmp
docker exec -i <your_container_id> /tmp/your-shell-script.sh

Precaution

Not all containers allow to run shell scripts in their context. You can check it executing any shell command in docker:

docker exec -i <your_container_id> echo "Shell works"

For future reference check section Understand how CMD and ENTRYPOINT interact

Docker Exec One-liner

docker exec -i <your_container_id> sh -c 'sh-command-1 && sh-command-2 && sh-command-n'

If your container has sh or bash or BusyBox shell wrapper (such as alpine, you can send one-line shell script to container's shell.

Limitations:

• only short scripts;
• hard to pass command-line arguments;
• only if your container has shell.

Docker Copy and Execute Script

docker cp ~/your-shell-script.sh <your_container_id>:/tmp
docker exec -i <your_container_id> /tmp/your-shell-script.sh -arg1 -arg2

You can copy script from host to container and then execute it.

You can pass arguments to the script.

You can run script with root credentials with -u root: docker exec -i -u root <your_container_id> /tmp/your-shell-script.sh -arg1 -arg2

You can run script interactively with -t: docker exec -it <your_container_id> /tmp/your-shell-script.sh -arg1 -arg2

Limitations:

• one more command to execute;
• only if your container has shell.