Unable to export calendar as ICS file under OC 10.0

Today I have upgraded OC from 9.1.4 to 10.0.

My operating system is FreeBSD 11.0-RELEASE-p10.

Upgrade process worked without problem after having disabled calendar and contacts apps. I could manually fix the oc_dav_shares table as described here:

Sync process against Android using DAVdroid is working without any issue so far.

Usually I do export my calendar as ICS file using the usual export URL with curl. This fails now with the following message:
<?xml version="1.0" encoding="utf-8"?>

3.2.2
Sabre\DAV\Exception\NotFound
Principal with name users not found

So tried to export my calendar using the webGUI which gives the following error:
Internal Server Error
Technical details
Remote Address: xx.xx.xx.xx
Request ID: x0zKZwGPe5ISPJ4u9Wip
(Real local IP replaced with xx.xx.xx.xx.)

I searched the forum but could not find a hint to this error. Is this issue already known?

Might be caused by the broken "old" CardDAV URL in 10.0. If you're familiar on how to patch your installation please help testing:

Just to make things clear: I DO NOT have any sync problems as I DO USE THE NEW sync links for my Android sync app:
https://$oc_server_fqdn/owncloud/remote.php/dav/

Instead I am unable to export my calendar using this link which still worked under OC 9.1.4:
https://$oc_server_fqdn/owncloud/remote.php/dav/calendars/$user/personal?export

Things would be easier, if the exact links for contacts and calendar export would be documented. I am using OC since version 3 and those links have changed several times. The changes were never cleanly documented and I had to test the correct links out. Please could you check my above export URL for the calendars and please correct it if it should be wrong due to another change.

By the way: The export link for addressbooks has definitely changed from OC 9.1.4 to OC 10.0. The now working URL is:
https://$oc_server_fqdn/owncloud/remote.php/dav/addressbooks/users/$user/contacts?export

The URLs where changed between 8.2.x and 9.0.0 for the last time. If there is something broken between 9.1.4 and 10.0.0 then please report this directly to the developers at https://github.com/owncloud/core/issues

Its not only about sync, the "old" URLs are not working at all so it would have caused your issue here if you had used the old URLs.

As it is essential for data security to save my current calendar and contacts to ics and vcf files I did some more testing.

Thanks for feedback about the URLs. The contacts URL at least did not really change but turned out to work under 9.1.4 in two flavours:
https://$oc_server_fqdn/owncloud/remote.php/dav/addressbooks/users/$user/contacts?export
https://$oc_server_fqdn/owncloud/remote.php/dav/addressbooks/$user/contacts?export
Under OC 10.0, however, only the first version works correctly.

It turns out, that newly created calendars can be saved without problems. As a workaround I created a new calendar and imported the latest (right before the backup) ics file. The import, however, hangs without error message. While importing I could further use OC from the browser and when back to the calendar the import dialog has disappeared. I straight exported the calendar to a file and compared the imported and exported files: Missing about 150 VEVENTS.

To make tests complete: An import of my contacts failed as well. This time, however, an error appeared: Multiple PRODID entries makes the importer refuse to work. Although I could solve this be deleting ALL PRODID entries I did no further tests.

As I spent meanwhile hours of testing I decided to to a manual downgrade to the previous OC 9.1.4 port, which in fact was a reinstallation with a subsequent import of my contacts and calendar file. The import of both my contacts and my calendar went just fine under OC 9.1.4.

Summary: I have full understanding that a major release upgrade reveals several new errors and smaller issues. However, I cannot understand why basic functionality is obviously not tested at all BEFORE releasing OC 10.0. At least two severe errors could have been easily detected before:

1.) Missing calendar due to the initially described wrong conversion of at least one table.
2.) Broken import of contacts and calendars.

I am observing now these severe problems with both calendar and contacts apps with major release upgrades and it every time took me many hours to get my data saved and find a workaround. For me and obviously many others these two apps are and essential part of OC which is expected to work in a reliable way - even after a major release upgrade. But obviously there has never been focus on these two apps under OC. I am tired fearing data loss with every major release upgrade and seriously take into account of migrating away to an alternative with focus on these two apps.

Unfortunately, I cannot even write a helpful Github issue on my observations, because there are no or only very limited error messages which are not helpful for developers. So I hope, this feedback can be helpful instead.

Just throwing this in:

TBH: if everybody waits until the final release we are stuck in this mess ... this is actually why 10.0.0 has issues like this. Weeks ahead we did release betas and release candidates but nobody tests them.
Once release all start crying: why is this broken!

If a service like DropBox or facebook or box.net or google or ... are buggy you are allowed to scream (to some extend) at them. ownCloud is a OpenSource project - each and every installation is unique and the complexity in testing the full system is beyond the capabilities of a company or a team or a single person. But using the community crowd to test the shit out of it we can further minimize the risk.

And yes ... there will never be a perfect release - we can only minimize the risk of regressions and bugs

-> https://github.com/owncloud/calendar/issues/794#issuecomment-299038597

which is absolutely true. If only a handful of the thousands of oC users would follow this advice we wouldn't need to discuss this here (especially as you're just talking to other users in here).

Thanks pointing me to the related but as well unresolved issue.

I do not want to blame all OC developers and do not want to extend any quality discussion but want to point to the ever repeating issue: Calendar and contacts app are developed separately. With every major release upgrade these apps do severely fail because obviosuly no developer even makes the quick basic tests to avoid issues 1.) and 2.) of my previous post, e.g. 1.) check, if calendar is still available and 2.) import ics file into OC after upgrade. Furthermore, I agree with you that DETAILED tests need to be done by the community.

The special situation of the OC contacts and calendar app is that they are not part of the core OC development. So I am afraid that the situation will not change. In other words: The quality of the calendar and contacts app will always lag behind the GOOD quality of the OC core.

I think that you forget that the calendar and contacts apps are not responsible for this current two points you're mentioning. Since oC 9.0.x the CalDAV and CardDAV functionality are now in the oC core (thats why the posted links above all leading to the "core" issue tracker).

You can use this functionality even without having both apps installed. They are now just "clients" like Thunderbird or DAVdroid.

The linked last issue is solved and included in the upcoming oC 10.0.1 which would be a version you should first consider to upgrade a productive environment to (its even better to wait two releases, e.g. for 10.0.2 to upgrade to).

Good point, thank you for clarifying that "CalDAV and CardDAV functionality are now in the oC core". I am not aware of this and the corresponding oC documentation is at least slightly misleading in this point:
https://doc.owncloud.org/server/9.0/user_manual/pim/
https://doc.owncloud.org/server/10.0/user_manual/pim/

So I am wondering where I can get information on how to use the CalDAV and CardDAV server of oC 9.x or 10.x without the two client apps. It may be a good option for me to get rid of the calendar and contacts apps. Could I have imported ICS and VCF files even without the two apps and if yes: How?

One the other hand: If my issues are not to blame these two apps: Shouldn't the basic tests that I have described above have been done by the devolpers more than ever before releasing? Or does the non-detection of at least two basic errors reveal that the communication between the apps developer and the core team does not work well?

I fear this is getting to off-topic from your initial issue. If you want to chat with some developers about your points / critics you might want to jump to the IRC channel #owncloud-dev on freenode where you might find some people.

If you have suggestion to the documentation (something missing or not clear) just create a new issue at https://github.com/owncloud/documentation/issues and it might be picked up by some one.

Just some final words:

IMHO developers should never be the ones doing the final testings. Additionally you're saying that no testing where done without knowing that. Maybe it got tested but not detected during these tests?

Or it got tested but not fully tested because there are other features with higher priority for the initial major release (e.g you think its an important feature, others thinks that it just a goodie with low priority).

Sure, you're right, we are driving slightly off-topic. And thank you very much for your advice of the production ready oC release.

Could you finally please give me some source for further reading about the CalDAV/CardDAV server of the oC core as the above mentioned official documentation is misleading to me.

EDIT: One last note: Originally I have posted my issue at #owncloud on freenode where I have been advised to use the forum instead :wink: But of course it was not the developer channel #owncloud-dev.