Pass environment variable from linux to docker container

Question

I am using docker-compose like this:

version: "2"
services:
  3dominator:
    build: .
    image: 3dominator:0.1
    container_name: 3dominator
    environment:
      NODE_ENV: development
      DB_ENV: container
      DOCKERHOST: $${DOCKERHOST}
    ports:
      - "3004:3004"
    volumes:
      - ./src:/app/src
    links:
      - 3dominatordb
      - 3dominatores
     ...
     ...

I want to pass a variable DOCKERHOST from my linux environment to docker container environment.

How to do that?

Possible duplicate of [How to use environment variables in docker compose](http://stackoverflow.com/questions/29377853/how-to-use-environment-variables-in-docker-compose) — Rao, Mar 23 '17 at 18:44

score 1 · Answer 1 · answered Mar 23 '17 at 19:03

1

Two options:

environment:
  - DOCKERHOST: ${DOCKERHOST}

Or since you are using the same variable name, you can shorten that to:

environment:
  - DOCKERHOST

answered Mar 23 '17 at 19:03

BMitch

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score 0 · Answer 2 · answered Mar 23 '17 at 19:06

0

You're almost there. Just remove one of the $ signs:

https://docs.docker.com/compose/compose-file/#variable-substitution

By having two dollar signs, you're preventing Compose from substituting the shell value for the variable.

answered Mar 23 '17 at 19:06

Djelibeybi

78
7

Pass environment variable from linux to docker container

2 Answers2