Hi, I have a question. I am using Pants in Bitbucket pipelines to build several Docker images. I'm tagging my images using the

{pants.hash}

option. For some reason, each time I run the deployment process (even on the same commit), I receive different hash values. However, when I do this locally, it seems to work fine. Does anyone have any insights into why this might be happening?

Does the CI pipeline change the file system? Eg download any files or install anything in the repo? A step to track down what’s changing might be getting the output of

pants peek

on the image and all its transitive dependencies (I’m on my phone so I can’t suggest the appropriate shell pipeline, sorry), and comparing them between different retries. (In theory, the output can include hashes of files, but maybe only in 2.18 (prerelease); I don’t recall) And/or running

git status

and

git diff

before the pants command

The

pants.hash

is calculated based on build args, build env and build context digest: https://github.com/pantsbuild/pants/blob/43828adfdbe982931ee0c79e39fce3b859c564c3/src/python/pants/backend/docker/util_rules/docker_build_context.py#L130-L134 So any of those three seems to not be stable during your bitbucket pipeline runs. If you’re able to run with

--keep-sandboxes=always

you should be able to inspect the sandbox and the

__run.sh

script in there to find the differences.

(I just checked,

pants peek ::

includes a`source_fingerprint` hash in Pants 2.16 and newer, so diffing the output of

pants dependencies --transitive path/to:image | xargs pants peek

between two runs would hopefully identify if it's a file or configuration change. You can do a similar diff on the output of

env

to see if there's interesting environment variable changes, if that might be a source of problems too)