feat: add upcoming events calendar

.github/workflows/deploy-cloudflare-workers.yml

@@ -52,7 +52,10 @@ jobs:
 
   deploy:
     name: Deploy Cloudflare Worker
-    if: github.repository == 'devcongress/website' && github.event_name != 'pull_request' && github.ref == 'refs/heads/main'
+    if: >-
+      github.repository == 'devcongress/website' &&
+      github.ref == 'refs/heads/main' &&
+      (github.event_name == 'schedule' || github.event_name == 'workflow_dispatch')
     needs: validate-and-build
     runs-on: ubuntu-latest
     environment:

README.md

@@ -56,6 +56,17 @@ credentials or connecting the browser directly to the operational system.
 Pushes to `main`, manual workflow runs, and the daily `06:17 UTC` scheduled
 build refresh the static event snapshot.
 
+## Event calendar subscription
+
+`/events/calendar.ics` is a public iCalendar subscription generated from the
+same validated Events Management feed as `/events/`. It includes only published
+events that are still in progress or have not started at build time; past events
+remain available on the website but are not carried into subscribers' calendars.
+
+The Events page links the feed to Google Calendar. The feed is refreshed by the
+same push, manual, and daily builds described above. No organizer credentials or
+unmoderated submissions are included.
+
 ## Public event submission launch controls
 
 Event submissions use one fail-closed build-time flag. Add it as a GitHub

src/layouts/Base.astro

@@ -189,11 +189,11 @@ const site        = siteEntries[0]!.data;
     cursor: pointer;
   }
 
-  .btn:hover {
+  .btn:not(:disabled):hover {
     transform: translate(-2px, -2px);
     box-shadow: var(--shadow-solid);
   }
-  .btn:active {
+  .btn:not(:disabled):active {
     transform: translate(0, 0);
     box-shadow: none;
   }

src/lib/event-calendar.ts

@@ -0,0 +1,114 @@
+import type { WebsiteEvent } from "./events";
+
+const CALENDAR_NAME = "DevCongress Events";
+const CALENDAR_DESCRIPTION =
+  "Published DevCongress meetups, workshops, hackathons, webinars, and conferences.";
+const CALENDAR_ORIGIN = "https://devcongress.org";
+
+export function upcomingCalendarEvents(
+  events: WebsiteEvent[],
+  now = new Date(),
+): WebsiteEvent[] {
+  const nowTime = now.getTime();
+  return [...events]
+    .filter((event) => new Date(event.endsAt).getTime() >= nowTime)
+    .sort(
+      (left, right) =>
+        new Date(left.startsAt).getTime() - new Date(right.startsAt).getTime(),
+    );
+}
+
+export function createEventsCalendar(
+  events: WebsiteEvent[],
+  now = new Date(),
+): string {
+  const calendarLines = [
+    "BEGIN:VCALENDAR",
+    "VERSION:2.0",
+    "PRODID:-//DevCongress//Events Calendar//EN",
+    "CALSCALE:GREGORIAN",
+    "METHOD:PUBLISH",
+    `X-WR-CALNAME:${escapeIcsText(CALENDAR_NAME)}`,
+    `X-WR-CALDESC:${escapeIcsText(CALENDAR_DESCRIPTION)}`,
+    "REFRESH-INTERVAL;VALUE=DURATION:P1D",
+    "X-PUBLISHED-TTL:P1D",
+  ];
+
+  for (const event of upcomingCalendarEvents(events, now)) {
+    const eventUrl = resolveEventUrl(event);
+    const description = [event.summary, eventUrl ? `More details: ${eventUrl}` : null]
+      .filter(Boolean)
+      .join("\n\n");
+
+    calendarLines.push(
+      "BEGIN:VEVENT",
+      `UID:${escapeIcsText(`${event.id}@events.devcongress.org`)}`,
+      `DTSTAMP:${formatIcsDate(event.updatedAt)}`,
+      `DTSTART:${formatIcsDate(event.startsAt)}`,
+      `DTEND:${formatIcsDate(event.endsAt)}`,
+      `SUMMARY:${escapeIcsText(event.title)}`,
+      `DESCRIPTION:${escapeIcsText(description)}`,
+      `LOCATION:${escapeIcsText(eventLocation(event))}`,
+      ...(eventUrl ? [`URL:${eventUrl}`] : []),
+      "STATUS:CONFIRMED",
+      "END:VEVENT",
+    );
+  }
+
+  calendarLines.push("END:VCALENDAR");
+  return calendarLines.map(foldIcsLine).join("\r\n") + "\r\n";
+}
+
+function resolveEventUrl(event: WebsiteEvent): string | null {
+  if (event.detailsUrl) return new URL(event.detailsUrl, CALENDAR_ORIGIN).toString();
+  return event.registrationUrl ?? event.onlineUrl;
+}
+
+function eventLocation(event: WebsiteEvent): string {
+  if (event.locationType === "online") return "Online";
+  const physicalLocation = [event.venueName, event.venueAddress]
+    .filter(Boolean)
+    .join(", ");
+  if (event.locationType === "hybrid") {
+    return physicalLocation ? `${physicalLocation} + online` : "Hybrid";
+  }
+  return physicalLocation || "In person";
+}
+
+function formatIcsDate(value: string): string {
+  const date = new Date(value);
+  if (!Number.isFinite(date.getTime())) throw new Error("Invalid calendar date");
+  return date.toISOString().replace(/[-:]/g, "").replace(/\.\d{3}Z$/, "Z");
+}
+
+function escapeIcsText(value: string): string {
+  return value
+    .replaceAll("\\", "\\\\")
+    .replaceAll("\r\n", "\\n")
+    .replaceAll("\n", "\\n")
+    .replaceAll(",", "\\,")
+    .replaceAll(";", "\\;");
+}
+
+function foldIcsLine(line: string): string {
+  const encoder = new TextEncoder();
+  const chunks: string[] = [];
+  let chunk = "";
+  let byteLength = 0;
+
+  for (const character of line) {
+    const characterBytes = encoder.encode(character).byteLength;
+    const limit = chunks.length === 0 ? 75 : 74;
+    if (byteLength + characterBytes > limit && chunk) {
+      chunks.push(chunk);
+      chunk = character;
+      byteLength = characterBytes;
+    } else {
+      chunk += character;
+      byteLength += characterBytes;
+    }
+  }
+  if (chunk || chunks.length === 0) chunks.push(chunk);
+
+  return chunks.join("\r\n ");
+}

src/lib/events.ts

@@ -141,6 +141,7 @@ export interface WebsiteEvent {
   organizerWebsite: string | null;
   coverUrl: string | null;
   detailsUrl: string | null;
+  updatedAt: string;
 }
 
 let eventsPromise: Promise<WebsiteEvent[]> | undefined;
@@ -243,6 +244,7 @@ async function fetchMeetupFallback(): Promise<WebsiteEvent[]> {
     organizerWebsite: "https://devcongress.org",
     coverUrl: meetup.data.cover,
     detailsUrl: `/meetups/${meetup.id}/`,
+    updatedAt: meetup.data.start,
   }));
 }
 
@@ -268,6 +270,7 @@ function mapPublicEvent(event: PublicEvent): WebsiteEvent {
     coverUrl: resolveOptionalWebsiteUrl(event.cover_url),
     detailsUrl:
       event.ownership === "devcongress" ? `/meetups/${event.slug}/` : null,
+    updatedAt: event.updated_at,
   };
 }
 

src/pages/events/calendar.ics.ts

@@ -0,0 +1,17 @@
+import type { APIRoute } from "astro";
+import { createEventsCalendar } from "../../lib/event-calendar";
+import { getEvents } from "../../lib/events";
+
+export const prerender = true;
+
+export const GET: APIRoute = async () => {
+  const calendar = createEventsCalendar(await getEvents());
+
+  return new Response(calendar, {
+    headers: {
+      "Content-Type": "text/calendar; charset=utf-8",
+      "Content-Disposition": 'inline; filename="devcongress-events.ics"',
+      "Cache-Control": "public, max-age=3600",
+    },
+  });
+};