feat: generate calendars for league events

backend/pyproject.toml

@@ -15,6 +15,7 @@ dependencies = [
   "fastapi~=0.110.1",
   "google-auth~=2.29.0",
   "httpx~=0.27.0",
+  "icalendar~=5.0.12",
   "piccolo==0.119.0",
   "uvicorn~=0.29.0",
   "requests~=2.31.0"
@@ -26,6 +27,7 @@ optional-dependencies.dev = [
   "respx~=0.21.1",
   "ruff~=0.3.5",
   "time-machine~=2.14.1",
+  "types-icalendar~=5.0.0",
   "types-requests~=2.31.0"
 ]
 

backend/requirements.txt

@@ -43,6 +43,7 @@ h11==0.14.0
 httpcore==1.0.5
     # via httpx
 httpx==0.27.0
+icalendar==5.0.12
 idna==3.6
     # via
     #   anyio
@@ -74,9 +75,15 @@ pydantic==1.10.15
     # via
     #   fastapi
     #   piccolo
+python-dateutil==2.9.0.post0
+    # via icalendar
+pytz==2024.1
+    # via icalendar
 requests==2.31.0
 rsa==4.9
     # via google-auth
+six==1.16.0
+    # via python-dateutil
 sniffio==1.3.1
     # via
     #   anyio

backend/src/routes/leagues.py

@@ -1,7 +1,9 @@
 import asyncio
 from typing import Awaitable, Iterable
 
+import icalendar
 from fastapi import Depends, Path
+from fastapi.responses import PlainTextResponse
 from fastapi.routing import APIRouter
 
 from ..database import (
@@ -166,6 +168,59 @@ async def get_league_events(
     return events
 
 
+def generate_event_calendar_description(event: EventWithLeagueDetails) -> str:
+    description = ""
+
+    if event.organiser:
+        description += f"Organised by {event.organiser}\n"
+    if event.part_of:
+        description += f"Part of {event.part_of}\n"
+    if event.more_information:
+        description += f"\n{event.more_information}\n"
+    if event.website:
+        description += f"\nFor more information, see the event website: {event.website}"
+
+    if event.results_links:
+        description += "\nResults:\n"
+        for destination, link in event.results_links.values():
+            description += f"\n  {destination}: {link}"
+
+    return description
+
+
+@router.get("/{league_name}/events/calendar")
+async def get_league_events_calendar(
+    league_name: str = Path(
+        title="League Name",
+        description="Name of the league to get the results for",
+        example="Sprintelope 2021",
+    ),
+) -> PlainTextResponse:
+    league, events = await asyncio.gather(
+        Leagues.get_by_name(league_name),
+        Events.get_by_league(league_name),
+    )
+
+    if not league:
+        raise HTTP_404(f"Couldn't find league with name `{league_name}`")
+
+    calendar = icalendar.Calendar()
+    calendar["name"] = league.name
+
+    for event in events:
+        calendar_event = icalendar.Event()
+        calendar_event.add("summary", f"{league.name} - {event.name}")
+        calendar_event.add("description", generate_event_calendar_description(event))
+        calendar_event.add("dtstart", event.date)
+        calendar_event.add("location", event.name)
+        calendar_event.add("url", event.website)
+        calendar_event.add("transp", "TRANSPARENT")  # doesn't show as busy
+
+        calendar.add_component(calendar_event)
+
+    return PlainTextResponse(calendar.to_ical(), media_type="text/calendar")
+
+
 def get_results_for_event(
     event: LeagueEvent, league_class: LeagueClass
 ) -> Awaitable[Iterable[Result]]:

backend/src/types/ics.pyi

@@ -0,0 +1,22 @@
+from datetime import date
+from typing import Iterable
+
+class Calendar:
+    events: set[Event]
+    def __init__(self) -> None: ...
+    def serialize_iter(self) -> Iterable[str]: ...
+
+class Event:
+    def __init__(
+        self,
+        name: str | None,
+        begin: date | None,
+        description: str | None,
+        location: str | None,
+        url: str | None,
+        organizer: Organizer | None,
+    ) -> None: ...
+    def make_all_day(self) -> None: ...
+
+class Organizer:
+    def __init__(self, email: str | None, common_name: str | None) -> None: ...