[BUG] caldav radicale compatibility / caldav priority issues

[grasegger]

Describe the bug

Setting up the tool with a radicale server results in errors about inserting items.

To Reproduce

• Setup radicale (development setup is enough)
• Setup syncall to use radicale
• Add task to taskwarrior and execute syncall

Jan 16 16:12:27 1337F00D uvx[2765511]: 16:12:27.35 | ERROR | [caldav Insert an item using the given side helper] Operation failed.

Expected Behavior

Tasks are successfully added to radicale

📸 Screenshots

Versions

OS Version (cat /etc/*-release; uname -a)

Fedora release 41 (Forty One)
NAME="Fedora Linux"
VERSION="41 (Forty One)"
RELEASE_TYPE=stable
ID=fedora
VERSION_ID=41
VERSION_CODENAME=""
PLATFORM_ID="platform:f41"
PRETTY_NAME="Fedora Linux 41 (Forty One)"
ANSI_COLOR="0;38;2;60;110;180"
LOGO=fedora-logo-icon
CPE_NAME="cpe:/o:fedoraproject:fedora:41"
DEFAULT_HOSTNAME="fedora"
HOME_URL="https://fedoraproject.org/"
DOCUMENTATION_URL="https://docs.fedoraproject.org/en-US/fedora/f41/system-administrators-guide/"
SUPPORT_URL="https://ask.fedoraproject.org/"
BUG_REPORT_URL="https://bugzilla.redhat.com/"
REDHAT_BUGZILLA_PRODUCT="Fedora"
REDHAT_BUGZILLA_PRODUCT_VERSION=41
REDHAT_SUPPORT_PRODUCT="Fedora"
REDHAT_SUPPORT_PRODUCT_VERSION=41
SUPPORT_END=2025-12-15

Linux 1337F00D 6.12.6-200.fc41.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Dec 19 21:06:34 UTC 2024 x86_64 GNU/Linux

Python version (python --version; python3 --version)

3.13.1

--version of your executable

tw_caldav_sync, version 1.8.8

Additional context

Edit
Just cloned the project and ran it with python 3.8.20 - same error.
Edit2
Looks like it has something to do with priority of an item being emtpy, not sure.
Edit3
Yes, def. something with priority, if I set it to 5 in the add_item function it works. I have not used priority, maybe thats the problem.
Edit4
Hm, now sync has stopped working, not with an error, just no output at all.

Edit5
Ok, yeah, once I add a priority to all my tasks sync works. The script makes the assumption that every user has priorities set up and that those priorities are not empty.

Edit6
Additional bug? Items are duplicated on the server, then duplicated locally, because fetching does not care about priorities at all and inserts them without any. Each sync the items are duplicated.

Since priorities are not a default in taskwarrior I would recommend ignoring it or using X-SYNCALL-PRIORITY instead of the priority field. I do not feel confident enough in the codebase to provide a PR at this point.