Add CI_PROJECT_PATH_SLUG variable
Proposal
Along the lines of the CI_BUILD_REF_SLUG
and CI_ENVIRONMENT_SLUG
variables there should be a CI_PROJECT_PATH_SLUG
variable.
Use case
The Docker-in-docker way of building images on Gitlab CI seems to be frowned upon and cumbersome.
The only alternatives I found are using the shell executor or mounting the docker socket. In both cases, build scripts must take care that they use unique identifiers, so for example instead of creating a container named "temp" they would create a container named "my-group-my-project-temp".
A CI_PROJECT_PATH_SLUG
variable would simplify this. A build script template could for example use docker run --name "$CI_PROJECT_PATH_SLUG-temp" ...
and it would be guaranteed that the container name would never clash with any other project using the same runner.