I am looking at assigning variables to an entry point script at runtime. I am working on dockerizing one of our internal applications. In my ENTRYPOINT script I have defined some logic to create a database.php file which will include the DB Username and Password. I'd like to run something similar to the following. How do I define DB_USERNAME and DB_PASSWORD as values read on run time?
docker run -d --name some-app -e DB_USERNAME=secret_username -e DB_PASSWORD=securepassword
The trick is to ensure you use the shell form of (preferably) ENTRYPOINT:
FROM busybox
ENTRYPOINT echo "Hello ${DOG}"
Then:
docker build --rm --file="Dockerfile" --tag58944222:latest .
docker run --interactive --tty --env=DOG=Freddie 58944222:latest
Returns:
Hello Freddie
Unclear why this was down-voted.
Hopefully this will help:
#!/bin/sh
echo "Hello ${DOG}"
And:
FROM busybox
ENV DOG=Henry
COPY ./test.sh .
RUN chmod +x ./test.sh
ENTRYPOINT ./test.sh
Returns the same results as before. The addition of the ENV Dog=Henry to the Dockerfile serves to provide default values:
docker run --interactive --tty 58944222:latest
Hello Henry
docker run --interactive --tty --env=DOG=Freddie 58944222:latest
Hello Freddie