feat(events): store short timezone label on Buzz Event

buzz/api/__init__.py

@@ -233,6 +233,7 @@ def get_event_booking_data(event_route: str) -> dict:
 			"start_time": event_doc.start_time,
 			"end_time": event_doc.end_time,
 			"time_zone": event_doc.time_zone,
+			"time_zone_label": event_doc.time_zone_label,
 			"venue": event_doc.venue,
 			"medium": event_doc.medium,
 			"category": event_doc.category,

buzz/api/forms.py

@@ -229,6 +229,7 @@ def get_custom_form_data(event_route: str, form_route: str) -> dict:
 		"start_time": event_doc.start_time,
 		"end_time": event_doc.end_time,
 		"time_zone": event_doc.time_zone,
+		"time_zone_label": event_doc.time_zone_label,
 		"venue": event_doc.venue,
 		"medium": event_doc.medium,
 		"short_description": event_doc.short_description,

buzz/events/doctype/buzz_event/buzz_event.json

@@ -18,6 +18,7 @@
   "start_date",
   "start_time",
   "time_zone",
+  "time_zone_label",
   "column_break_cjby",
   "end_date",
   "end_time",
@@ -175,6 +176,12 @@
    "fieldtype": "Autocomplete",
    "label": "Time Zone"
   },
+  {
+   "fieldname": "time_zone_label",
+   "fieldtype": "Data",
+   "label": "Time Zone Label",
+   "read_only": 1
+  },
   {
    "fieldname": "banner_image",
    "fieldtype": "Attach Image",
@@ -595,7 +602,7 @@
    "link_fieldname": "event"
   }
  ],
- "modified": "2026-03-23 17:37:37.770911",
+ "modified": "2026-07-23 12:00:00.000000",
  "modified_by": "Administrator",
  "module": "Events",
  "name": "Buzz Event",

buzz/events/doctype/buzz_event/buzz_event.py

@@ -5,10 +5,10 @@
 from frappe import _
 from frappe.model.document import Document
 from frappe.model.naming import append_number_if_name_exists
-from frappe.utils.data import get_time, time_diff_in_seconds
+from frappe.utils.data import get_datetime, get_time, time_diff_in_seconds
 
 from buzz.api.forms import validate_excluded_fields
-from buzz.utils import only_if_app_installed
+from buzz.utils import get_time_zone_label, only_if_app_installed
 
 # Top-level dashboard route segments (/b/<segment>) an event route must not shadow.
 RESERVED_EVENT_ROUTES = {
@@ -84,6 +84,7 @@ class BuzzEvent(Document):
 		ticket_email_template: DF.Link | None
 		ticket_print_format: DF.Link | None
 		time_zone: DF.Autocomplete | None
+		time_zone_label: DF.Data | None
 		title: DF.Data
 		venue: DF.Link | None
 	# end: auto-generated types
@@ -95,6 +96,17 @@ def validate(self):
 		self.validate_tax_settings()
 		self.validate_guest_verification_config()
 		self.validate_custom_forms()
+		self.set_time_zone_label()
+
+	def set_time_zone_label(self):
+		# validate runs before the mandatory check, so dates may still be empty here
+		if not (self.time_zone and self.start_date and self.start_time):
+			self.time_zone_label = ""
+			return
+
+		# computed at event start so DST zones get the abbreviation in effect then
+		event_start = get_datetime(f"{self.start_date} {self.start_time}")
+		self.time_zone_label = get_time_zone_label(self.time_zone, event_start)
 
 	def validate_custom_forms(self):
 		for form in self.custom_forms:

buzz/events/doctype/buzz_event/test_buzz_event.py

@@ -10,6 +10,8 @@
 from buzz.api import are_registrations_closed
 from buzz.events.doctype.buzz_event.buzz_event import RESERVED_EVENT_ROUTES, create_from_template
 from buzz.events.doctype.event_template.event_template import create_template_from_event
+from buzz.patches.set_time_zone_label_for_existing_events import execute as backfill_time_zone_labels
+from buzz.utils import get_time_zone_label
 
 
 class TestBuzzEvent(FrappeTestCase):
@@ -890,3 +892,133 @@ def test_event_end_fallback_is_also_timezone_consistent(self):
 		after_end = datetime(2026, 6, 15, 16, 31, 0, tzinfo=timezone(timedelta(hours=5, minutes=30)))
 		with patch("buzz.api.get_datetime_in_timezone", return_value=after_end):
 			self.assertTrue(are_registrations_closed(event))
+
+
+class TestTimeZoneLabel(FrappeTestCase):
+	"""Tests for get_time_zone_label: IANA name -> short display label."""
+
+	def test_tzdb_abbreviation_when_alphabetic(self):
+		"""Zones where tzdata ships a real abbreviation use it directly."""
+		reference = datetime(2026, 6, 15, 12, 0)
+		self.assertEqual(get_time_zone_label("Asia/Kolkata", reference), "IST")
+		self.assertEqual(get_time_zone_label("Asia/Tokyo", reference), "JST")
+		self.assertEqual(get_time_zone_label("Africa/Nairobi", reference), "EAT")
+		self.assertEqual(get_time_zone_label("UTC", reference), "UTC")
+
+	def test_dst_variant_follows_reference_date(self):
+		"""DST zones get the abbreviation in effect on the reference date."""
+		winter = datetime(2026, 1, 15, 12, 0)
+		summer = datetime(2026, 7, 15, 12, 0)
+		self.assertEqual(get_time_zone_label("America/New_York", winter), "EST")
+		self.assertEqual(get_time_zone_label("America/New_York", summer), "EDT")
+		self.assertEqual(get_time_zone_label("Europe/Berlin", winter), "CET")
+		self.assertEqual(get_time_zone_label("Europe/Berlin", summer), "CEST")
+
+	def test_curated_abbreviation_when_tzdb_is_numeric(self):
+		"""Zones where tzdata returns a bare offset fall back to the curated map."""
+		reference = datetime(2026, 6, 15, 12, 0)
+		self.assertEqual(get_time_zone_label("Asia/Dubai", reference), "GST")
+		self.assertEqual(get_time_zone_label("Asia/Riyadh", reference), "AST")
+		self.assertEqual(get_time_zone_label("Asia/Bangkok", reference), "ICT")
+		self.assertEqual(get_time_zone_label("Asia/Kathmandu", reference), "NPT")
+
+	def test_gmt_offset_fallback_for_unmapped_zone(self):
+		"""Zones outside tzdata abbreviations and the curated map show a GMT offset."""
+		reference = datetime(2026, 6, 15, 12, 0)
+		# Bhutan: tzname is "+06", not in the curated map
+		self.assertEqual(get_time_zone_label("Asia/Thimphu", reference), "GMT+6")
+		# Myanmar: half-hour offset formatting
+		self.assertEqual(get_time_zone_label("Asia/Yangon", reference), "GMT+6:30")
+		# Marquesas: negative half-hour offset
+		self.assertEqual(get_time_zone_label("Pacific/Marquesas", reference), "GMT-9:30")
+
+	def test_empty_or_invalid_time_zone_returns_empty(self):
+		reference = datetime(2026, 6, 15, 12, 0)
+		self.assertEqual(get_time_zone_label(None, reference), "")
+		self.assertEqual(get_time_zone_label("", reference), "")
+		self.assertEqual(get_time_zone_label("Not/A_Zone", reference), "")
+
+	def test_current_iana_names_for_renamed_zones(self):
+		"""Renamed zones resolve under both the legacy and current IANA names."""
+		reference = datetime(2026, 6, 15, 12, 0)
+		self.assertEqual(get_time_zone_label("Asia/Ho_Chi_Minh", reference), "ICT")
+		self.assertEqual(get_time_zone_label("America/Nuuk", reference), "WGT")
+
+	def test_aware_reference_datetime_converted_not_reinterpreted(self):
+		"""US DST ends 2026-11-01 06:00 UTC; 05:30 UTC is still 01:30 EDT.
+
+		Naive .replace() would read 05:30 as New York wall clock (past the
+		switch, EST); a correct conversion lands on EDT.
+		"""
+		aware_reference = datetime(2026, 11, 1, 5, 30, tzinfo=timezone.utc)
+		self.assertEqual(get_time_zone_label("America/New_York", aware_reference), "EDT")
+
+
+class TestEventTimeZoneLabelField(FrappeTestCase):
+	"""Saving a Buzz Event stores the display label for its time zone."""
+
+	def tearDown(self):
+		frappe.db.rollback()
+
+	def _make_event(self, **overrides):
+		event_defaults = {
+			"doctype": "Buzz Event",
+			"title": "TZ Label Test Event",
+			"category": "Test Category",
+			"host": "Test Host",
+			"start_date": "2026-03-05",
+			"end_date": "2026-03-06",
+			"start_time": "9:00:00",
+			"end_time": "18:00:00",
+		}
+		event_defaults.update(overrides)
+		return frappe.get_doc(event_defaults)
+
+	@classmethod
+	def setUpClass(cls):
+		super().setUpClass()
+		TestBuzzEvent.create_test_fixtures()
+
+	def test_label_set_on_insert(self):
+		event = self._make_event(time_zone="Asia/Kolkata")
+		event.insert()
+		self.assertEqual(event.time_zone_label, "IST")
+
+	def test_label_updates_when_time_zone_changes(self):
+		event = self._make_event(time_zone="Asia/Kolkata")
+		event.insert()
+		event.time_zone = "Asia/Dubai"
+		event.save()
+		self.assertEqual(event.time_zone_label, "GST")
+
+	def test_label_cleared_when_time_zone_removed(self):
+		event = self._make_event(time_zone="Asia/Kolkata")
+		event.insert()
+		event.time_zone = ""
+		event.save()
+		self.assertEqual(event.time_zone_label, "")
+
+	def test_label_uses_event_start_date_for_dst(self):
+		"""July New York event shows EDT, not EST."""
+		event = self._make_event(
+			time_zone="America/New_York",
+			start_date="2026-07-10",
+			end_date="2026-07-10",
+		)
+		event.insert()
+		self.assertEqual(event.time_zone_label, "EDT")
+
+	def test_backfill_patch_skips_events_missing_start_fields(self):
+		"""Legacy rows can have time_zone without start fields; patch must not abort."""
+		event = self._make_event(time_zone="Asia/Kolkata")
+		event.insert()
+		frappe.db.set_value(
+			"Buzz Event",
+			event.name,
+			{"start_time": None, "time_zone_label": ""},
+			update_modified=False,
+		)
+
+		backfill_time_zone_labels()
+
+		self.assertEqual(frappe.db.get_value("Buzz Event", event.name, "time_zone_label"), "")

buzz/patches.txt

@@ -11,4 +11,5 @@ buzz.patches.migrate_offline_payment_to_methods
 buzz.patches.populate_slug_in_event_category
 buzz.patches.set_applies_to_for_existing_coupons
 buzz.patches.set_payment_status_for_existing_bookings
-buzz.patches.normalize_phone_format
+buzz.patches.normalize_phone_format
+buzz.patches.set_time_zone_label_for_existing_events

buzz/patches/set_time_zone_label_for_existing_events.py

@@ -0,0 +1,20 @@
+import frappe
+from frappe.utils.data import get_datetime
+
+from buzz.utils import get_time_zone_label
+
+
+def execute():
+	events = frappe.get_all(
+		"Buzz Event",
+		filters={
+			"time_zone": ("is", "set"),
+			"start_date": ("is", "set"),
+			"start_time": ("is", "set"),
+		},
+		fields=["name", "time_zone", "start_date", "start_time"],
+	)
+	for event in events:
+		event_start = get_datetime(f"{event.start_date} {event.start_time}")
+		label = get_time_zone_label(event.time_zone, event_start)
+		frappe.db.set_value("Buzz Event", event.name, "time_zone_label", label, update_modified=False)

buzz/utils.py

@@ -1,8 +1,12 @@
 import functools
+import re
 from collections.abc import Callable
+from datetime import datetime
+from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
 import frappe
 from frappe.custom.doctype.custom_field.custom_field import create_custom_fields
+from frappe.utils import now_datetime
 
 
 def is_app_installed(app_name: str) -> bool:
@@ -189,3 +193,84 @@ def generate_ics_file(event_doc, attendee_email: str):
 
 	# nosemgrep: frappe-semgrep-rules.rules.security.frappe-ssti
 	return frappe.render_template("templates/ics/ics.jinja2", context, is_path=True)
+
+
+# Curated abbreviations for zones where tzdata only provides a numeric offset
+# (tzdata dropped invented abbreviations in 2017). Zones with real tzdata
+# abbreviations (IST, EST, CET, ...) never reach this map.
+# ponytail: DST-observing zones here (e.g. Chile) are pinned to their standard
+# form; extend get_time_zone_label with per-date variants if that ever matters.
+TIMEZONE_ABBREVIATIONS = {
+	"America/Araguaina": "BRT",
+	"America/Argentina/Buenos_Aires": "ART",
+	"America/Bogota": "COT",
+	"America/Caracas": "VET",
+	"America/Godthab": "WGT",
+	"America/Nuuk": "WGT",
+	"America/Lima": "PET",
+	"America/Montevideo": "UYT",
+	"America/Santiago": "CLT",
+	"America/Sao_Paulo": "BRT",
+	"Asia/Aden": "AST",
+	"Asia/Almaty": "ALMT",
+	"Asia/Baghdad": "AST",
+	"Asia/Bahrain": "AST",
+	"Asia/Baku": "AZT",
+	"Asia/Bangkok": "ICT",
+	"Asia/Dacca": "BST",
+	"Asia/Dhaka": "BST",
+	"Asia/Dubai": "GST",
+	"Asia/Ho_Chi_Minh": "ICT",
+	"Asia/Irkutsk": "IRKT",
+	"Asia/Kabul": "AFT",
+	"Asia/Kathmandu": "NPT",
+	"Asia/Krasnoyarsk": "KRAT",
+	"Asia/Kuwait": "AST",
+	"Asia/Muscat": "GST",
+	"Asia/Novosibirsk": "NOVT",
+	"Asia/Qatar": "AST",
+	"Asia/Riyadh": "AST",
+	"Asia/Saigon": "ICT",
+	"Asia/Tashkent": "UZT",
+	"Asia/Tehran": "IRST",
+	"Asia/Yekaterinburg": "YEKT",
+	"Atlantic/Azores": "AZOT",
+	"Atlantic/Cape_Verde": "CVT",
+	"Europe/Istanbul": "TRT",
+}
+
+
+def get_time_zone_label(time_zone: str | None, reference_datetime: datetime | None = None) -> str:
+	"""Short display label for an IANA time zone, e.g. "IST", "GST", "GMT+5:45".
+
+	Resolution order: tzdata abbreviation for the reference date (DST-aware),
+	then the curated map, then a formatted GMT offset.
+	"""
+	if not time_zone:
+		return ""
+
+	try:
+		zone = ZoneInfo(time_zone)
+	except (ZoneInfoNotFoundError, ValueError):
+		return ""
+
+	reference = reference_datetime or now_datetime()
+	if reference.tzinfo:
+		moment = reference.astimezone(zone)
+	else:
+		moment = reference.replace(tzinfo=zone)
+
+	abbreviation = moment.tzname()
+	if re.fullmatch(r"[A-Z]{2,5}", abbreviation):
+		return abbreviation
+
+	if time_zone in TIMEZONE_ABBREVIATIONS:
+		return TIMEZONE_ABBREVIATIONS[time_zone]
+
+	total_minutes = int(moment.utcoffset().total_seconds()) // 60
+	sign = "+" if total_minutes >= 0 else "-"
+	hours, minutes = divmod(abs(total_minutes), 60)
+	label = f"GMT{sign}{hours}"
+	if minutes:
+		label += f":{minutes:02d}"
+	return label

dashboard/src/components/EventDetailsHeader.vue

@@ -45,8 +45,8 @@
 					<div>
 						<p class="font-medium text-ink-gray-8">
 							{{ formatEventTime(eventDetails.start_time, eventDetails.end_time) }}
-							<span v-if="eventDetails.time_zone"
-								>({{ eventDetails.time_zone }})</span
+							<span v-if="eventDetails.time_zone_label"
+								>({{ eventDetails.time_zone_label }})</span
 							>
 						</p>
 					</div>

dashboard/src/types/Events/BuzzEvent.ts

@@ -34,6 +34,8 @@ export interface BuzzEvent {
 	start_time?: string
 	/**	Time Zone : Autocomplete	*/
 	time_zone?: any
+	/**	Time Zone Label : Data	*/
+	time_zone_label?: string
 	/**	End Date : Date	*/
 	end_date?: string
 	/**	End Time : Time	*/