Docker-compose gives error when docker run works with same environment, volumes and devices

Question

I have a Python3 app on Raspberry Pi 3 (arm32v7). The app takes a picture at regular time intervals with picamera, detects motion using image analysis with Pillow, detects objects using deep-learning with Tensorflow and sends an annotated image with base64-encoding as JSON payload to an MQTT broker for further processing and display in a gallery with Node-RED.

I have containerized the app using Docker to install on a fleet of old Pi's. I am able to build an image containing the necessary Python packages and then create a container with docker run command to launch the app. This works as expected, however the command is a very long line of text. To streamline, I created a docker-compose YML. I am able to create a container and launch the app but it fails to run properly.

Here is the docker run command, with env. variables, shared volume and shared device:

docker run --name nonamenow --rm --env USERID=admin --env PASSWD='wrongp@$$wordtryagain' --env MQTTIP='192.168.1.219' --env DELTA=60 --privileged=true -v /opt/vc:/opt/vc --env LD_LIBRARY_PATH=/opt/vc/lib --device /dev/vchiq -it sentry2:envenabled

Creating a container in this way works fine and images start flowing into the gallery. Now, here is the docker-compose YAML I used with docker-compose up.

version: '3.6'

services:
  app:
    build: .
    container_name: sentrycam21
    image: sentry2:envenabled
    restart: always
    privileged: true
    environment:
    - LD_LIBRARY_PATH=/opt/vc/lib
    - USERID=admin
    - PASSWD='wrongp@$$wordtryagain'
    - MQTTIP='192.168.1.219'
    - DELTA=90
    - TOPIC=Surveillance/MainDoor
    volumes:
    - /opt/vc:/opt/vc
    devices: 
    - "/dev/vchiq:/dev/vchiq"

This fails at runtime, when the program attempts to connect to the MQTT broker. Note that the connection is established correctly by the other method with the same parameters. I tried removing the quotes around the IP address but then it just hangs and nothing further happens.

Please let me know if you see any obvious errors in my docker-compose YAML. Grateful for your help.

Answer 1

- MQTTIP='192.168.1.219'

is not equal to

- "MQTTIP=192.168.1.219"

the later is the one you want i guess.

2. if you put a dollar sign in a compose file you ned to double it.

    - "PASSWD=wrongp@$$$$wordtryagain"

ps : you can try to print env like this in python to validate point (1):

import os
print(os.environ)