Write a file in a docker container and read from another container-CodePudding

I have a project like this structure:

app
    - selenium
        - downloads
.env
docker-compose.yml

docker-compose.yml has 2 services: myApp and selenium. And this volumes set for my services:

myApp:

volumes:
  - ./app:/home/app

selenium:

volumes:
  - ./app/selenium/downloads:/home/seluser/Downloads

When I run docker compose up in this directory, My application and selenium run up and I can develop my application. sometimes I need the selenium container for getting some content around the web.

When selenium container downloads a file, this file is stored in the ./app/selenium/downloads and I can read this file from the myApp container.

Problem

When I changed the selenium default download directory to /home/seluser/Downloads/aaa/bbb, this directory can access by the selenium container with /home/app/selenium/downloads/aaa/bbb, But I can't access aaa directory in the myApp container.

I can Change the permission of the aaa directory with the root user in the myApp container and solve this problem, But the default download directory can be changed for every downloaded file.

What's the solution to this problem?

CodePudding user response：

I guess that you are getting troubles because your main processes of your 2 containers are running with different user. There is an easy way is to modify your Dockerfile and set the same user id (UID) for these both users. So the file/directory generated by a container can be accessed properly by the user of the other container.

An example Dockerfile to create a user with specified UID

ARG UNAME=testuser
ARG UID=1000
ARG GID=1000
RUN groupadd -g $GID -o $UNAME
RUN useradd -m -u $UID -g $GID -o -s /bin/bash $UNAME

There is another way using umask to assign proper permission to file/directory generated in your selenium container (to grant READ access to all users). But I think it's more complicated and make take your time to know which umask is suitable for you https://phoenixnap.com/kb/what-is-umask