Docker container 100 questions

• Communication between Docker containers?

  • Mq of container connection host
  • A rabbitmq container has been created on the Linux host, and a service container xxx has been created. How does this xxx connect to the rabbitmq container? Because it's all on a Linux, it doesn't seem to work for me to fill in the localhost + port in the xxx service container. Change localhost to the intranet ip, such as (192.168.31.100), but it doesn’t work if it’s the intranet IP. Net IP will change

Q: How to collect Docker container logs?
A:

Q: By docker-compose of env_file option is to copy .env file into the container, or simply set the environment variable?

A: Just simply set the environment variables, and will not .env file in the host machine to the container, but just .env to ask the container's environment variables.

You can use the code below to test it yourself 👇

main.py

import os


# print(os.environ)

print(os.environ['HOST'], type(os.environ['HOST']))
print(os.environ['PORT'], type(os.environ['PORT']))


print(os.getcwd())
print(os.listdir())

Build mirror sudo docker build -t "testing/docker_log" .

Dockerfile

FROM python:3.9.9-slim
ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
COPY main.py /code/

Run container docker-compose up

docker-compose.yaml

version: "3"
services:
  docker_log_service:
    container_name: docker_log_service
    image: testing/docker_log
    network_mode: "host"
    env_file:
      - .env
    command: python main.py