Hi folks , I'm setting up Pants in GitLab CI for building/pushing Docker images with DinD but hitting some roadblocks. Anyone here managed to integrate Pants with DinD in CI, especially around Docker config? Would appreciate any tips or pointers on best practices and common pitfalls. Thanks!

14:54:57.71 [DEBUG] computed 1 nodes in 0.323865 seconds. there are 1822 total nodes.

`364145457.71 [DEBUG] Canceled: Finding the

tar

binary - environment:linux_docker`

36514:54:57.71 [ERROR] 1 Exception encountered:

366Engine traceback:

367  in select

368    ..

369  in pants.core.goals.package.package_asset

`370

package

goal`

371Traceback (most recent call last):

372  File "/root/.cache/nce/f60c448851c3b3112b179a56f168ee90d8597297cfc45d3ca7178c6715f6cba8/bindings/venvs/2.19.0/lib/python3.9/site-packages/pants/core/goals/package.py", line 165, in package_asset

373    packages = await MultiGet(

374  File "/root/.cache/nce/f60c448851c3b3112b179a56f168ee90d8597297cfc45d3ca7178c6715f6cba8/bindings/venvs/2.19.0/lib/python3.9/site-packages/pants/engine/internals/selectors.py", line 374, in MultiGet

375    return await _MultiGet(tuple(__arg0))

376  File "/root/.cache/nce/f60c448851c3b3112b179a56f168ee90d8597297cfc45d3ca7178c6715f6cba8/bindings/venvs/2.19.0/lib/python3.9/site-packages/pants/engine/internals/selectors.py", line 172, in __await__

377    result = yield self.gets

378native_engine.IntrinsicError: Failed to obtain version from local Docker: error trying to connect: No such file or directory (os error 2)

379

Yes - have you allowed

DOCKER_HOST

to be passed through to Pants? https://www.pantsbuild.org/2.18/docs/docker#docker-configuration

[docker]
build_args = ["USER", "HOME", "PATH", "GIT_COMMIT_SHA"]
tools = ["docker",]
env_vars = [
  "DOCKER_HOST=<tcp://docker:2376>"
]

no luck same error ^_^

I use GitLal, docker-in-docker, and Pants

Could you share some details about your setup?

We run use self managed amd64 and arm64 runners in k8s with docker-in-docker enabled. If you add

docker info

to the job before doing anything with Pants, does that work?

yes it works

`364145457.71 [DEBUG] Canceled: Finding the

tar

binary - environment:linux_docker` Are you using environments?

yes

ah, Environments I am not using. If you search for your error message you will see a few different threads. Perhaps the issue is the value of

DOCKER_HOST

or https://github.com/pantsbuild/pants/issues/18915

yes i confirm that the issue comes from this option

I think I've found a workaround for Environments breaking the DOCKER_HOST setting for docker builds. Added to https://github.com/pantsbuild/pants/issues/18915

Hi Guys, Sorry to follow up on an older thread, but has there been any progress on this issue? I am new to pants, and we have a gitHub-ci setup where the build is failing with the following error:

ERROR: Cannot connect to the Docker daemon at unix:///var/run/docker.sock

@adventurous-pillow-38958 - no progress I'm aware of. You need to make sure

DOCKER_HOST

is added to the docker subsystem env vars so that the non-default value for gitlab (apparently

DOCKER_HOST=<tcp://localhost:2375>

) is picked up.

I'm also seeing this issue. There isn't much support out there for Gitlab CI/CD. @adventurous-pillow-38958 have you made any progress?

Hey @ancient-australia-38408 I got this error in GitHub CI. As a workaround, for repo's using pants we have switched to shell executor, as we faced this error when using the Docker executor *

Hey Anandhu, thanks for the response. I did end up solving this a different way so I'll share here. I plan on publishing a Gitlab CI/CD component for pants so stay tuned!

# .gitlab-ci.yml

variables:
  PANTS_CONFIG_FILES: "pants.ci.toml"
  DOCKER_HOST: "<tcp://docker:2375>"
  DOCKER_TLS_CERTDIR: ""

# pants.ci.toml

[docker]
tools = ["docker-credential-gcloud", "dirname", "readlink", "python3"]
env_vars = ["DOCKER_HOST=<tcp://docker:2375>", "DOCKER_TLS_CERTDIR=''"]

Hello everyone, I'm encountering a similar issue while using a self-hosted GitHub runner with Docker-in-Docker. Unfortunately, the suggested solution hasn't resolved my problem. 🤔 Here's a snippet from my

pants.ci.toml

file:

[docker]
env_vars = ["DOCKER_HOST=unix:///home/runner/var/run/docker.sock"]

However, the

pants package

command is failing with the following error:

2025-05-24T21:55:51.7662147Z Engine traceback:
2025-05-24T21:55:51.7662412Z   in `package` goal
2025-05-24T21:55:51.7662568Z
2025-05-24T21:55:51.7662949Z ProcessExecutionFailure: Process 'Building docker image docker-dev:latest' failed with exit code 1.
2025-05-24T21:55:51.7663528Z stdout:
2025-05-24T21:55:51.7663653Z
2025-05-24T21:55:51.7663763Z stderr:
2025-05-24T21:55:51.7664221Z ERROR: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

Interestingly, I don't see any reference to my custom settings in the logs. I expected

DOCKER_HOST

to be mentioned in the environment variables under:

spawned local process as Some(18479) for Process { argv: ["/usr/bin/docker", "buildx", "build", "--output=type=docker", "--pull=False", "--tag", "docker-dev:latest", "--file", "src/python/apps/ml_gateway/Dockerfile.docker-dev", "."], env: {"PATH": "/tmp/pants-sandbox-HrsgbT/_binary_shims_8f03118fb0b8f813fc0212ed7e946ef3cc99a30a46e3e2069b4fad2f63eb3882", "__UPSTREAM_IMAGE_IDS": ""}, ... execution_environment: ProcessExecutionEnvironment { name: Some("local_linux"), platform: Linux_x86_64, strategy: Local }, remote_cache_speculation_delay: 0ns, attempt: 0 }

Any guidance on how to further investigate this issue would be greatly appreciated! Thank you!