The existing question How to view log output using docker-compose run allows me to interactively view docker compose run logs. But for Gitlab CI/CD I need the output from all involved containers on stdout.
A simple workaround would appear to be docker log --follow & beforehand but in that case the CI/CD pipeline does not terminate, which causes it to fail with a timeout.
As a minimal example, using:
CMD ['echo', 'Hello, World']
in a Dockerfile, run that with docker compose run HelloWorld.
Desired output: "Hello, World"
Current output: ""
The workaround I've found is to move the entire test to a shell script, gitlab-ci-client.sh. This script is the only thing called by Gitlab CI/CD.
Using the HelloWorld container example from the question, that gives me
#! /bin/bash
# Between docker compose and gitlab ci yaml nonsense, logging is hard.
# This shell script avoids the need to define tests in yaml,
# and the log tailing is under process control
COMPOSE="docker compose -f docker-compose.tests.yml -f docker-compose.gitlab.yml"
# Preparation stage
$COMPOSE logs --tail 0 --follow &
$COMPOSE build
echo -e "\e[32mDocker images built, starting tests...\e[0m"
EXIT=0
$COMPOSE run HelloWorld || EXIT=1
if [ $EXIT -eq 0 ] ; then
echo -e "\e[32mTests passed\e[0m"
else
echo -e "\e[33;1mTests failed, result=${EXIT}\e[0m"
fi
# Cleanup. You can't do this from Gitlab CI/CD, and without this cleanup the CI/CD pipeline hangs
$COMPOSE down
pkill -P $$
echo -e "\e[32mCleanup finished\e[0m"
exit $EXIT