docker - 使用ENV参数设置容器PATH

Question

我有一个包含以下内容的docker-compose文件:

 environment:
      DOCUMENT_ROOT: /var/some/dir

我想将该路径添加到我的容器中。
在我的DockerFile中，添加:

RUN echo "export PATH=$PATH:${DOCUMENT_ROOT}" >> /root/.bashrc

但这是行不通的。看来ENV参数不可用。

有什么问题 ？

亚龙

Answer 1

ARG some_variable_name    
RUN echo "export PATH=$PATH:${some_variable_name}" >> /root/.bashrc

您应该在Dockerfile中使用 ARG并在build命令中设置参数:

docker build --build-arg some_variable_name=a_value

ARG is only available during the build of a Docker image (RUN etc), not after the image is created and containers are started from it (ENTRYPOINT, CMD). You can use ARG values to set ENV values to work around that.

或在docker-compose中:

version: '3'

services:
  somename:
    build:
      context: ./app
      dockerfile: Dockerfile
      args:
        some_variable_name: a_value

Understanding Docker Build Args, Environment Variables and Docker Compose Variables