Notifications and calendars

How to find out about schedule changes without asking the API every minute. Checked with booth d1 on October 23, 2026; the methods of this page are also available on production.

What to choose

Calendar Feed

GET /calendar/schedule.ics returns a schedule in iCalendar format with the same filters as GET /schedule: group or groupId, teacher or teacherId, scope, dateFrom, dateTo, and lessonIds and subjectIds (only these classes or subjects), locale (ru, en, zh) and attachment=1 (to give as a file).

• You don't need a key: it's the same schedule that any visitor sees.
• Subscribe to the address — the calendar itself rereads it and picks up edits, cancellations and deletions. Each activity has a constant UID, so the change updates the event rather than adding a second one.
• Time is with the time zone (DTSTART;TZID=Europe/Moscow:…).
• No more than 60 requests per minute from one address.

https://d1.vish-app.ru/api/v1/calendar/schedule.ics?group=ШАД-111

GET /session.ics is the same for the session.: exams, tests, and consultations with a group or teacher.

Change Feed

GET /schedule/changes — what has recently changed in the schedule of one group (groupId) or teacher (teacherId), new from above.

• period=recent (by default) — recent changes; limit — how many.
• period=weeks — changes in classes for this and next week.
• At the record: lessonId, change (created, announced, updated, deleted), subject, room, startAt, endAt, changedFields, changes ( field, was, became), origin (institute — revision at the institute, source — new university schedule) and createdAt.

How to poll: once every 5-15 minutes, memorizing id or createdAt of the last processed record, and process only what is newer. The answer from period=weeks is cached for a minute — it's pointless to ask more often.

Push in the browser

POST /push/subscriptions and POST /push/unsubscribe subscribe the browser of application VISH to notifications about changes to the group or teacher; the public VAPID key for subscription is in GET /app-config (push.publicKey). These methods are designed for the application VISH itself: the subscription is created by its service worker. The change feed is more convenient for your site or bot.

Example: feed and changes

The example downloads the calendar feed of a group, checks its format and uniqueness UID, and then reads the changes of this and next week. The group is VISH_GROUP, with ШАД-111 by default.

// The group's calendar feed and its recent changes; no key needed.
const API = process.env.VISH_API ?? 'https://d1.vish-app.ru/api/v1'
const GROUP = process.env.VISH_GROUP ?? 'ШАД-111'

const groups = await (await fetch(`${API}/groups?search=${encodeURIComponent(GROUP)}&all=1`)).json()
const group = groups.list.find((item) => item.name === GROUP)
if (!group) throw new Error(`group ${GROUP} not found`)

const feed = await fetch(`${API}/calendar/schedule.ics?group=${encodeURIComponent(GROUP)}`)
const calendar = await feed.text()
if (!feed.ok || !feed.headers.get('content-type')?.startsWith('text/calendar') || !calendar.startsWith('BEGIN:VCALENDAR')) {
	throw new Error(`not a calendar: HTTP ${feed.status}`)
}
const uids = [...calendar.matchAll(/^UID:(.+)$/gmu)].map((match) => match[1].trim())
if (new Set(uids).size !== uids.length) throw new Error('duplicate UIDs')

const response = await fetch(`${API}/schedule/changes?groupId=${group.id}&period=weeks`)
if (!response.ok) throw new Error(`changes: HTTP ${response.status}`)
const changes = (await response.json()).list
if (!Array.isArray(changes) || changes.some((item) => !item.lessonId || !item.change || !item.createdAt)) {
	throw new Error('unexpected changes answer')
}

console.log(`${GROUP}: ${uids.length} events in the feed, ${changes.length} changes this week and next`)
for (const item of changes.slice(0, 5)) {
	console.log(`- ${item.createdAt.slice(0, 16)} ${item.change}: ${item.subject?.ru ?? item.lessonId} (${item.changedFields?.join(', ') ?? ''})`)
}

To try

The current week, the call grid, and the public key for push:

Verified: 2026-10, PWA aa337c45, platform bff65fce._