fix: Give GetUserAvailability enough info to parse datetimes as tz-aw…

…are. Only warn about naive datetimes when they are unexpected. Fixes #1319

exchangelib/fields.py

@@ -598,9 +598,10 @@ class DateTimeBackedDateField(DateField):
     def __init__(self, *args, **kwargs):
         # Not all fields assume a default time of 00:00, so make this configurable
         self._default_time = kwargs.pop("default_time", datetime.time(0, 0))
-        super().__init__(*args, **kwargs)
         # Create internal field to handle datetime-only logic
         self._datetime_field = DateTimeField(*args, **kwargs)
+        kwargs.pop("allow_naive", None)
+        super().__init__(*args, **kwargs)
 
     def date_to_datetime(self, value):
         return self._datetime_field.value_cls.combine(value, self._default_time).replace(tzinfo=UTC)
@@ -665,6 +666,10 @@ class DateTimeField(FieldURIField):
 
     value_cls = EWSDateTime
 
+    def __init__(self, *args, **kwargs):
+        self.allow_naive = kwargs.pop("allow_naive", False)
+        super().__init__(*args, **kwargs)
+
     def clean(self, value, version=None):
         if isinstance(value, datetime.datetime):
             if not value.tzinfo:
@@ -686,8 +691,10 @@ def from_xml(self, elem, account):
                         tz = account.default_timezone
                         log.info("Found naive datetime %s on field %s. Assuming timezone %s", e.local_dt, self.name, tz)
                         return e.local_dt.replace(tzinfo=tz)
-                    # There's nothing we can do but return the naive date. It's better than assuming e.g. UTC.
-                    log.warning("Returning naive datetime %s on field %s", e.local_dt, self.name)
+                    if not self.allow_naive:
+                        # There's nothing we can do but return the naive date. It's better than assuming e.g. UTC.
+                        # Making this a hard error is probably too risky. Warn instead.
+                        log.warning("Returning naive datetime %s on field %s", e.local_dt, self.name)
                     return e.local_dt
                 log.info("Cannot convert value '%s' on field '%s' to type %s", val, self.name, self.value_cls)
                 return None

exchangelib/properties.py

@@ -1857,7 +1857,8 @@ class AbsoluteDateTransition(BaseTransition):
 
     ELEMENT_NAME = "AbsoluteDateTransition"
 
-    date = DateTimeBackedDateField(field_uri="DateTime")
+    # Values are returned as naive, and we have no timezone to hook up the values to yet
+    date = DateTimeBackedDateField(field_uri="DateTime", allow_naive=True)
 
 
 class RecurringDayTransition(BaseTransition):

exchangelib/protocol.py

@@ -511,6 +511,7 @@ def get_free_busy_info(self, accounts, start, end, merged_free_busy_interval=30,
 
         tz_definition = list(self.get_timezones(timezones=[start.tzinfo], return_full_timezone_data=True))[0]
         return GetUserAvailability(self).call(
+            tzinfo=start.tzinfo,
             mailbox_data=[
                 MailboxData(
                     email=account.primary_smtp_address if isinstance(account, Account) else account,

exchangelib/services/get_user_availability.py

@@ -1,3 +1,5 @@
+from collections import namedtuple
+
 from ..properties import FreeBusyView
 from ..util import MNS, create_element, set_xml_value
 from .common import EWSService
@@ -11,9 +13,14 @@ class GetUserAvailability(EWSService):
 
     SERVICE_NAME = "GetUserAvailability"
 
-    def call(self, mailbox_data, timezone, free_busy_view_options):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.tzinfo = None
+
+    def call(self, tzinfo, mailbox_data, timezone, free_busy_view_options):
         # TODO: Also supports SuggestionsViewOptions, see
         #  https://docs.microsoft.com/en-us/exchange/client-developer/web-service-reference/suggestionsviewoptions
+        self.tzinfo = tzinfo
         return self._elems_to_objs(
             self._chunked_get_elements(
                 self.get_payload,
@@ -23,8 +30,13 @@ def call(self, mailbox_data, timezone, free_busy_view_options):
             )
         )
 
+    @property
+    def _timezone(self):
+        return self.tzinfo
+
     def _elem_to_obj(self, elem):
-        return FreeBusyView.from_xml(elem=elem, account=None)
+        fake_account = namedtuple("Account", ["default_timezone"])(default_timezone=self.tzinfo)
+        return FreeBusyView.from_xml(elem=elem, account=fake_account)
 
     def get_payload(self, mailbox_data, timezone, free_busy_view_options):
         payload = create_element(f"m:{self.SERVICE_NAME}Request")