calendars fails to find user directory from principals, due to changes in sabre dav between 3.0.9 and 3.2.2 (https://github.com/sabre-io/dav/issues/755). Upstream fixed owncloud for this compatibility issue there: https://github.com/owncloud/core/commit/6b8e8edcffdcf2b525e5f26683b42fe0485cc2e8#diff-1aec04ba25037067a4d2c1fc323ed253
See also https://bugzilla.redhat.com/show_bug.cgi?id=1525208
It appears that that commit first appeared in the 10.0.0 release of OwnCloud core. I have no idea if it would cleanly backport to 9.1.5, but hopefully it could be backported without too much trouble as I presume the 10.0.0 might not be backward compatible (is it? I'm not sure, just guessing based on the version bump.)
I spent a bit of time today trying to see how cleanly the patch would backport to the 9.1.5 release. It was mostly pretty clean except for the tests, which are not run by the spec file. I did find that the resulting patch did not apply nicely together with the many other patches applied in the spec file, however, so it was non-trivial. There is also a 9.1.7 release of owncloud, but it does not support the newer sabredav either.
Currently, for Fedora 27, I just had to downgrade php-sabre-dav to version 3.0.9 to have a working owncloud 9.1.5 instance. And now for Fedora 28, I also have to apply this patch: https://github.com/nextcloud/server/pull/5072/commits/b8f2418248312826f1ccb9d7cf942f8844e02f7b With these two modifications in Fedora 28, I have an instance of owncloud 9.1.5 that basically still works for me (files, contacts, and calendar).
This message is a reminder that Fedora 28 is nearing its end of life. On 2019-May-28 Fedora will stop maintaining and issuing updates for Fedora 28. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At that time this bug will be closed as EOL if it remains open with a Fedora 'version' of '28'. Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Fedora version. Thank you for reporting this issue and we are sorry that we were not able to fix it before Fedora 28 is end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora, you are encouraged change the 'version' to a later Fedora version prior this bug is closed as described in the policy above. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete.
Fedora 28 changed to end-of-life (EOL) status on 2019-05-28. Fedora 28 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.
FWIW the problem is still there in Fedora 30. I had to downgrade php-sabre-dav to version 3.0.9 to have a working owncloud-9.1.5 installation. So I reopen the bug.
This message is a reminder that Fedora 30 is nearing its end of life. Fedora will stop maintaining and issuing updates for Fedora 30 on 2020-05-26. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At that time this bug will be closed as EOL if it remains open with a Fedora 'version' of '30'. Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Fedora version. Thank you for reporting this issue and we are sorry that we were not able to fix it before Fedora 30 is end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora, you are encouraged change the 'version' to a later Fedora version prior this bug is closed as described in the policy above. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete.
Fedora 30 changed to end-of-life (EOL) status on 2020-05-26. Fedora 30 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.