CalDAV sync works only 1 time, not fully thereafter

[geowas-github]

After adding a new CalDAV account successfully, the tasks of 1 out of my 2 calendars there is synced. For the second calendar the sync circle goes round and round. For any other sync there is the warning triangle saying "connection to server failed".

However, the connection seems to be up:
When adding or changing a task in Planify, this is still synced to the server
On the other hand, a task added or changed in a different client on the smartphone does not reach Planify. (No problem with the other client: when deleting and re-adding the account in Planify, then also the added/updated task is visible in Planify after initial sync).
So: outgoing sync works, incoming sync fails, error "connection to server failed" is not (completely) true.

Expected behavior
outgoing sync works, incoming sync works

Desktop (please complete the following information):

• OS or DE: Linux Mint 22.2 XFCE
• 7.14.0 (flatpak)

[obsti8383]

I have the same issue with posteo.de CalDav (Linux OpenSuse, Planify 4.17.0 (flatpak)). Log says:

** (io.github.alainm23.planify:2): WARNING **: 19:30:31.821: Core.vala:281: Failed to sync: REPORT https://posteo.de:8443/calendars/myaccountname/default/ failed: HTTP 403 Forbidden
<?xml version="1.0" encoding="utf-8"?>
<d:error xmlns:d="DAV:" xmlns:s="http://sabredav.org/ns">
  <s:exception>Sabre_DAV_Exception_ReportNotSupported</s:exception>
  <s:message/>
  <d:supported-report/>
</d:error>

[Vadoola]

I seem to be having the same issue, Planify 4.17 installed from AUR, using KolabNow and custom domain.

I'm not in front of my computer right now, so I'll have to try and update later with logs.

[geowas-github]

Update on behaviour with latest version 4.18.0:
outgoing sync works (new/updated/deleted tasks from Planify to CalDAV server) ✅
incoming sync fails (new/updated/deleted tasks from CalDAV server to Planify) ❌
error "connection to server failed" is gone.

[Tarzuma]

I have the same issue:
OS: Linux Mint 22.3 Cinnamon

• Application: Planify 4.18.0 flatpak
• CalDAV provider: Posteo (https://posteo.de)

Planify is able to connect to my Posteo CalDAV account and successfully downloads existing calendar entries.
However, two-way synchronization does not appear to work:

• New events created on the Posteo web interface do not appear in Planify.
• New events created in Planify do not appear on the Posteo web calendar.
• Planify shows no error messages and appears to sync normally, but no changes are exchanged in either direction.

The same Posteo CalDAV calendar works correctly (two-way sync) with other CalDAV clients, so the server configuration and credentials are confirmed to be correct.

[iskrisis]

Same issue with CalDav on mailbox.org. Tested on two machines separately Fedora 43 and current version of Bazzite.

[axellieb]

Same problem (outgoing sync working/incoming sync not working), also with CalDAV on Mailbox.org, except I'm not getting any errors.

[fabianschoeppach]

I was having issues with our university server based on Horde.org. At first I notices discrepancies when trying to sync labels, and after a lot of trial and error, I ended up with exactly the same issue as you all:

Note

1. Initially the task lists are correctly synced via CalDAV, all tasks appear as they are on the server.
2. Any in Planify changes (adding tasks, changing title, label, due date, priority...) are correctly synced to the server.
3. After any incoming change, Planify won't sync anymore (in no direction). There is no error, the spinning arrow comes and goes, but no content updates appear. Deleting and re-adding the account resets this behaviour.

I am running Planify version 4.18.3 on Gnome 49 on Bluefin (Fedora Silverblue).

From the console after `flatpak run io.github.alainm23.planify`, I got some critical output messages (click to unwrap). But not sure if they are connected to this issue.

Application start (twice):

(io.github.alainm23.planify:2): GLib-GObject-CRITICAL **: 16:54:19.367: invalid (NULL) pointer instance

(io.github.alainm23.planify:2): GLib-GObject-CRITICAL **: 16:54:19.367: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed

After adding the CalDAV account and making some changes, the same messages as above plus some additional lines of:

** (io.github.alainm23.planify:2): CRITICAL **: 16:55:30.603: gxml_dom_node_get_text_content: assertion 'self != NULL' failed

** (io.github.alainm23.planify:2): CRITICAL **: 16:56:37.936: objects_project_get_inbox_section_hidded: assertion 'self != NULL' failed

** (io.github.alainm23.planify:2): CRITICAL **: 16:56:37.940: objects_project_get_inbox_section_hidded: assertion 'self != NULL' failed

** (io.github.alainm23.planify:2): CRITICAL **: 16:56:41.131: utils_datetime_get_todoist_datetime_format: assertion 'date != NULL' failed

After trying to sync external changes, the same as initially:

(io.github.alainm23.planify:2): GLib-GObject-CRITICAL **: 16:57:26.852: invalid (NULL) pointer instance

(io.github.alainm23.planify:2): GLib-GObject-CRITICAL **: 16:57:26.852: g_signal_connect_object: assertion 'G_TYPE_CHECK_INSTANCE (instance)' failed