gitlab runner and testcontainers with docker socket binding - docker

Question

I am using testcontainers to start a Postgresql DB for my junit test. Locally everything works fine. This is my small test project:
https://gitlab.com/janning/tpj-testcontainer
I can run the test inside my IDE and on CLI with ./gradlew test
Now I want to run it in my Gitlab-CI Pipeline but without docker-in-docker (dind). So I need to mount the docker socket, which is documented here: https://www.testcontainers.org/supported_docker_environment/continuous_integration/gitlab_ci/
so I configred my gitlab-runner like this:
concurrent = 1
check_interval = 0
[session_server]
session_timeout = 1800
[[runners]]
name = "kt103-tpj"
url = "https://gitlab.com"
token = "XXXXXXXXXXXXXXXXX"
executor = "docker"
[runners.docker]
tls_verify = false
image = "registry.gitlab.com/janning/tpj-testcontainer/debian:latest"
privileged = false
disable_entrypoint_overwrite = false
extra_hosts = ["host.docker.internal:host-gateway"]
oom_kill_disable = false
disable_cache = false
volumes = ["/var/run/docker.sock:/var/run/docker.sock", "/cache"]
shm_size = 0
First my gitlab-ci.yml builds a Dockerimage as I need openjdk-17 and some docker commands.
variables:
TESTCONTAINERS_HOST_OVERRIDE: "host.docker.internal"
stages:
- dockerimage
- test
dockerimage:
image: docker:latest
stage: dockerimage
before_script:
- docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
script:
- tag=":latest"
- docker build --pull -t "$CI_REGISTRY_IMAGE/debian${tag}" .
- docker push "$CI_REGISTRY_IMAGE/debian${tag}"
test:
stage: test
image: $CI_REGISTRY_IMAGE/debian:latest
script:
- echo $DOCKER_HOST
- echo $DOCKER_TLS_VERIFY
- echo $DOCKER_CERT_PATH
- ./gradlew test
artifacts:
when: always
reports:
junit: build/test-results/test/**/TEST-*.xml
The job "test" failed (complete log here)
Task :test HalloTest > test() FAILED
java.lang.IllegalStateException at RyukResourceReaper.java:129 1 test completed, 1 failed
Task :test FAILED
If i dig deeper into the junit result I can see the following stacktrace:
java.lang.IllegalStateException: Could not connect to Ryuk at host.docker.internal:49158
at org.testcontainers.utility.RyukResourceReaper.maybeStart(RyukResourceReaper.java:129)
at org.testcontainers.utility.RyukResourceReaper.init(RyukResourceReaper.java:42)
at org.testcontainers.DockerClientFactory.client(DockerClientFactory.java:203)
at ...
I guess it has something to do with the docker image, which I build. But I am stuck as I don't know what the problem is. I don't how to solve or debug this situation.
The ryuk container is started in my host which is running gitlab-runner. But it can't connect:
$ docker container logs -f ba62a173aafd
2022/06/24 09:42:51 Pinging Docker...
2022/06/24 09:42:51 Docker daemon is available!
2022/06/24 09:42:51 Starting on port 8080...
2022/06/24 09:42:51 Started!
panic: Timed out waiting for the first connection
goroutine 1 [running]:
main.main()
/go/src/github.com/testcontainers/moby-ryuk/main.go:50 +0x449

Answer 1

The problem was just a firewall problem blocking traffic between the docker containers. As I could reach any docker container from external, it took my quite a while until I realized it.