Configurable repository cache root directory path

[Gabriel-Ladzaretti]

Tell us more.

It is currently impossible to bind mount a repo cache file at the expected path when running a Renovate job as a docker container. this is because, if parent directories are not present in the container, they are created with root as the owner by default, and this docker behavior is not configurable. one such directory is the main cache directory, and when the cli tries to create a subdir, it fails with a permission error (e.g., __private_cache_dir).

one approach to address this limitation is to make the repo cache root directory configurable.
a current workaround is to bind mount the cache directory as well as the repo cache file, but this requires cleanup on the host, which is sub-optimal.

[rarkins]

What is the current approach/default Renovate uses?

[Gabriel-Ladzaretti]

is a dedicated config opt that defaults to the cache dir an acceptable solution ?

[rarkins]

Either way is ok

[Gabriel-Ladzaretti]

Actually, I much prefer a "no code" solution. as you said, most of the current logic resolving directories is pretty low level.

one such solution is to have the baseDir and the <baseDir>/cache directories pre-exist inside the container with 0775 permissions and :root ownership. this way, we won't have issues with write permissions. doing so enables us to both bind mount the repo cache file from outside the container and provide the appropriate directory permissions for renovate.

above means that the only change needed is creating these directories in the renovate docker image.

wdyt ?

[rarkins]

@viceice in which repo would this best be done?

[viceice]

i think it's best suited in renovate images.