How do I write a dockerfile to execute a simple bash script?
I’m trying to write a docker image to run a simple webserver though netcat.
So I have in my docker build folder:
Dockerfile index.html run_netcat_webserver.sh
run_netcat_webserver.sh is very simple and it works fine:
#!/bin/bash while true ; do nc -l 8080 < index.html ; done
Here is my naive Dockerfile that of course is not working:
FROM ubuntu:14.04 CMD run_netcat_webserver.sh
How should I proceed to make this work inside a docker container?
One Solution collect form web for “How do I write a dockerfile to execute a simple bash script?”
You need to make the script part of the container. To do that, you need to copy the script inside using the
COPY command in the Docker file, e.g. like this
FROM ubuntu:14.04 COPY run_netcat_webserver.sh /some/path/run_netcat_webserver.sh CMD /some/path/run_netcat_webserver.sh
/some/path is a path of your choice inside the container. Since you don’t need to care much about users inside the container, it can be even just
Another option is to provide the script externally, via mounted volume. Example:
FROM ubuntu:14.04 VOLUME /scripts CMD /scripts/run_netcat_webserver.sh
Then, when you run the container, you specify what directory will be mounted as
/scripts. Let’s suppose that your script is in
/tmp, then you run the container as
docker run --volume=/tmp:/scripts (rest of the command options and arguments)
This would cause that your (host) directory
/tmp would be mounted under the
/scripts directory of the container.