Files
Calendarr/backend/ical_io.py
T
ScarriffleandClaude Opus 5 aa795fde76 Stop one recurring event from taking its whole calendar down
An RRULE was parsed by splitting on ";" and "=", which leaves every value a
str. icalendar accepts that at add() time and only rejects it inside
to_ical(), where vRecur.types maps UNTIL to vDDDTypes and that demands a date.
So a single "repeats until <date>" event — exactly what the web editor writes —
made build_ics raise ValueError, and with it every REPORT, every event GET,
the whole-collection GET and the .ics export for that calendar.

PROPFIND never builds ICS, so discovery kept working. That is the asymmetry
behind the Home Assistant symptom: the calendar is found under its correct
name, then every update fails and the entity sits permanently unavailable. It
behaved identically through the token URL and the login URL because both reach
the same collection dispatch.

icalendar parses its own format correctly, so the rule now goes through
vRecur.from_ical. That parser can raise where the hand-rolled one silently
accepted anything, so an unreadable stored rule now drops the recurrence and
logs it instead of failing the calendar — the same tolerance the DTSTART and
DTEND parsing already has.

caldav_client carried a second copy of the same parser with the same defect,
used when pushing events to external CalDAV servers. Deleted; both directions
now share one.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-10-25 16:59:41 +01:00

238 lines
8.8 KiB
Python

"""iCal (.ics) import/export for local calendars.
Reuses the already-installed ``icalendar`` library. The parser produces dicts
matching the LocalEvent storage shape (ISO strings, comma-separated EXDATE);
the generator emits a VCALENDAR with ORGANIZER, RRULE, etc.
"""
from __future__ import annotations
import logging
import uuid
from urllib.parse import quote
from datetime import date, datetime, timedelta, timezone
from icalendar import Calendar, Event, vCalAddress, vRecur, vText, vUri
from icalendar.parser import Parameters
logger = logging.getLogger(__name__)
def _rrule_to_str(component) -> str | None:
prop = component.get("RRULE")
if not prop:
return None
return prop.to_ical().decode("utf-8")
def _exdate_to_csv(component) -> str | None:
"""Collect EXDATE values as comma-separated YYYYMMDD strings."""
exdate = component.get("EXDATE")
if not exdate:
return None
items = exdate if isinstance(exdate, list) else [exdate]
out = []
for ex in items:
dts = getattr(ex, "dts", None) or []
for d in dts:
val = d.dt
if isinstance(val, datetime):
out.append(val.strftime("%Y%m%d"))
elif isinstance(val, date):
out.append(val.strftime("%Y%m%d"))
return ",".join(out) if out else None
def _organizer_name(component) -> str | None:
org = component.get("ORGANIZER")
if not org:
return None
# CN parameter holds the display name; fall back to the mailto address.
try:
cn = org.params.get("CN")
if cn:
return str(cn)
except Exception:
pass
raw = str(org)
if raw.lower().startswith("mailto:"):
return raw[7:]
return raw or None
def parse_ics(raw: bytes) -> dict:
"""Parse .ics bytes into {"events": [dict, ...], "errors": [str, ...]}.
Raises ValueError if the payload is not a parseable calendar at all.
"""
try:
cal = Calendar.from_ical(raw)
except Exception as e:
raise ValueError(f"Datei ist kein gültiges iCal-Format: {e}") from e
events = []
errors = []
for component in cal.walk():
if component.name != "VEVENT":
continue
try:
uid = str(component.get("UID") or uuid.uuid4())
title = str(component.get("SUMMARY", "") or "")
location = str(component.get("LOCATION", "") or "") or None
description = str(component.get("DESCRIPTION", "") or "") or None
dtstart_prop = component.get("DTSTART")
if dtstart_prop is None:
errors.append(f"VEVENT {uid}: kein DTSTART, übersprungen")
continue
dtstart = dtstart_prop.dt
dtend_prop = component.get("DTEND")
duration_prop = component.get("DURATION")
all_day = isinstance(dtstart, date) and not isinstance(dtstart, datetime)
if all_day:
if dtend_prop:
dtend = dtend_prop.dt
elif duration_prop:
dtend = dtstart + duration_prop.dt
else:
dtend = dtstart + timedelta(days=1)
start_str = dtstart.isoformat()
end_str = (dtend.isoformat() if isinstance(dtend, date)
else (dtstart + timedelta(days=1)).isoformat())
else:
if dtstart.tzinfo is None:
dtstart = dtstart.replace(tzinfo=timezone.utc)
if dtend_prop:
dtend = dtend_prop.dt
if isinstance(dtend, date) and not isinstance(dtend, datetime):
dtend = datetime.combine(dtend, datetime.min.time(), tzinfo=timezone.utc)
elif dtend.tzinfo is None:
dtend = dtend.replace(tzinfo=timezone.utc)
elif duration_prop:
dtend = dtstart + duration_prop.dt
else:
dtend = dtstart + timedelta(hours=1)
start_str = dtstart.isoformat()
end_str = dtend.isoformat()
events.append({
"uid": uid,
"title": title,
"start": start_str,
"end": end_str,
"all_day": all_day,
"location": location,
"description": description,
"rrule": _rrule_to_str(component),
"exdate": _exdate_to_csv(component),
"organizer": _organizer_name(component),
})
except Exception as exc:
logger.warning("Skipping malformed VEVENT: %s", exc)
errors.append(f"Fehlerhafter Eintrag übersprungen: {exc}")
return {"events": events, "errors": errors}
def _rrule_str_to_vrecur(rrule_str: str) -> vRecur:
"""Parse an RRULE string into a vRecur with correctly typed values.
Hand-splitting on ";" and "=" leaves every value a str, which icalendar
accepts silently here and then rejects inside ``to_ical()``: vRecur.types
maps UNTIL to vDDDTypes, and that demands a date. A single "repeats until
<date>" event therefore made the whole calendar fail to serialise — a 500
on REPORT, on GET and on export, while PROPFIND kept working because it
never builds ICS. Letting icalendar parse its own format gives UNTIL as a
datetime and COUNT/INTERVAL as ints.
"""
return vRecur(vRecur.from_ical(rrule_str))
def _parse_iso(s: str) -> datetime:
s = s.replace("Z", "+00:00")
dt = datetime.fromisoformat(s)
if dt.tzinfo is None:
dt = dt.replace(tzinfo=timezone.utc)
return dt
def build_ics(calendar, events, *, name_cache: dict | None = None,
attachments_by_event: dict | None = None,
base_url: str | None = None) -> str:
"""Build a VCALENDAR string for a local calendar and its events.
``attachments_by_event`` maps LocalEvent.id -> list of EventAttachment. With
a ``base_url`` each one becomes an ATTACH property pointing at its
capability URL, so external clients (Apple Calendar, Thunderbird) can fetch
it — they cannot send a bearer token. Both arguments are optional so every
existing caller keeps working and emits no ATTACH at all.
"""
cal = Calendar()
cal.add("prodid", "-//Calendarr//EN")
cal.add("version", "2.0")
cal.add("x-wr-calname", calendar.name)
for ev in events:
item = Event()
item.add("uid", ev.uid)
item.add("summary", ev.title or "")
item.add("dtstamp", datetime.now(timezone.utc))
if ev.all_day:
try:
start = date.fromisoformat(ev.start[:10])
end = date.fromisoformat(ev.end[:10])
except ValueError:
continue
if end <= start:
end = start + timedelta(days=1)
item.add("dtstart", start)
item.add("dtend", end)
else:
try:
item.add("dtstart", _parse_iso(ev.start))
item.add("dtend", _parse_iso(ev.end))
except ValueError:
continue
if ev.location:
item.add("location", ev.location)
if ev.description:
item.add("description", ev.description)
if ev.color:
item.add("x-calendarr-color", ev.color)
if ev.rrule:
try:
item.add("rrule", _rrule_str_to_vrecur(ev.rrule))
except (ValueError, TypeError):
logger.warning("Skipping unparsable RRULE %r on event %s", ev.rrule, ev.id)
# ORGANIZER from the creator (local user or imported name).
organizer_name = None
if getattr(ev, "creator_id", None) and name_cache:
organizer_name = name_cache.get(ev.creator_id)
if not organizer_name:
organizer_name = getattr(ev, "creator_name_external", None)
if organizer_name:
organizer = vCalAddress("mailto:noreply@calendarr.local")
organizer.params["CN"] = vText(organizer_name.replace('"', ""))
item.add("organizer", organizer)
# ATTACH: one line per attachment, as a URI rather than inline base64 —
# the files are up to 10 MB each and would otherwise be copied into
# every ICS body on every sync.
for att in (attachments_by_event or {}).get(getattr(ev, "id", None), ()):
if not base_url:
continue # a relative ATTACH URL is useless to an external client
uri = vUri(f"{base_url}/api/attach/{att.token}/{quote(att.filename)}")
uri.params = Parameters({
"FMTTYPE": att.content_type,
"SIZE": str(att.size_bytes),
"FILENAME": att.filename,
})
item.add("attach", uri, encode=0)
cal.add_component(item)
return cal.to_ical().decode("utf-8")