How do I pass environment variables to Docker containers?

Question

I\'m new to Docker, and it\'s unclear how to access an external database from a container. Is the best way to hard-code in the connection string?

# Dockerfil         


        

Answer 1

Using jq to convert the env to JSON:

env_as_json=`jq -c -n env`
docker run -e HOST_ENV="$env_as_json" 

this requires jq version 1.6 or newer

this pust the host env as json, essentially like so in Dockerfile:

ENV HOST_ENV  (all env from the host as json)