Upgrade base image to Debian stretch

[fedde-s]

Debian stretch has replaced Debian jessie as the current stable release a few months ago by now. Switching the base image keeps the Docker image up to date, and upgrades OpenLDAP to release 2.4.44. This would fix the inconsistency I reported as issue #24. It might potentially cause minor breakage to automated setups built on the image, as the Debian changelog for the slapd package lists various (presumably minor, but not necessarily completely backwards-compatible) changes since version 2.4.40+dfsg-1.

[dinkel]

Thank you very much for this contribution, it is highly appreciated!

A first look at the patch looks very promising, as not much changed ;-).

Before merging I'd like to test at least my installation and read about the differences in the two OpenLDAP version to see if there are problems when updating an existing database to 2.4.44.

If everything works as desired, I think I am staying with only supporting one active version and not have different branches. As far as I understand, OpenLDAP is in a mature state where not many changes happen. Or do you see it differently?

I'll keep you informed!

[fedde-s]

I have limited experience with OpenLDAP; I was looking for a docker image to set up a quick server, but saw no reason to limit myself to the version released in the oldstable release of Debian. I have the impression that software included in a stable release of Debian has generally already been reviewed pretty thoroughly. Besides, most projects make a release number in which only the minor number has changed suggests that none of the changes affect how people are using APIs/CLIs. Changes in the way Debian patches and installs it may though: stretch is a new major release of Debian.

[fedde-s]

And after I upgraded for myself and found that my minimal testing worked as I expected, I decided that it would be good to contribute it back to the original project if you think it an improvement too 🙂

[dinkel]

Sorry for the long delay. I finally got to check your merge request and found it OK.

I had to make a slight change in the entrypoint.sh file (4709a52), so that it always updates the ownership of /etc/ldap/slapd.d/. In Jessie the owner and group of openldap were different (104/107 in Jessie, 101/101 in Stretch). Without this change, starting with an existing config would crash, because slapd could not read the config files.