When Rails in Docker goes to down...

🤔 Situation

• Environment

  • Rails 6.1
  • Rails in Docker
  • AWS EC2

• Fully works on development mode

• Don't work on EC2 with docker compose

🚀 Treatment

Check standard logs.
This command shows standard log.

docker ps

CONTAINER ID ... NAMES
36b68a26fc66 ... xxx_web_1

docker logs xxx_web_1
# it shows standard log

😅 In my case

The name of file and class are different.
The production mode eager loads all file before starting.
That's the why.

! Unable to load application: Zeitwerk::NameError: expected file /null_strategy.rb to define constant Strategies::Jobs::NullStrategy, but didn't