environment variables?

[ackvf]

Hello, is there a documentation for which env variables does heroku pass to the docker and to the app?

I need to access latest commit hash in the app.

[dmathieu]

We pass exactly the same environment variables to slugs and docker apps.
That means you can get access to the commit hash with the dyno-metadata feature: https://devcenter.heroku.com/articles/dyno-metadata

[ackvf]

Thank you for your answer, I did manage to get HEROKU_ variables in the env, however, the HEROKU_SLUG_COMMIT is empty. I guess it is not unexpected since I did not build from git push, but as you can see, the commit seems to be available in the scope under npm_package_gitHead, therefore I would expect in HEROKU_SLUG_COMMIT as well. Are my thoughts correct?
For reference.

[dmathieu]

This is because the docker push API doesn't allow us to provide any information such as a commit sha.
We cannot make the data available today unfortunately.