Event Check-in & Anonymous Identifiers

This document describes the event check-in system, anonymous registration flows, and how anonymous identifiers are used across the platform.

Check-in System Overview

The check-in system supports three primary flows:

Logged-in self check-in

Users with accounts check in from the event page or via token link

Token-based check-in

Anyone with a valid check-in token (QR code or link) can access check-in

Anonymous pick-your-registration

Unauthenticated users with a token search and select their registration to check in

Check-in Settings

Events can configure check-in behavior via checkInSettings:

Setting	Description
`allowEarlyCheckIn`	Allow check-in before event start time
`allowAnonymousCheckIn`	Enable anonymous (FormResponse) registrations in check-in list
`allowOnPageCheckIn`	Allow check-in from the event page (vs. token link only)
`requireRegistration`	Require registration before check-in (logged-in users)
`autoCheckIn`	Automatically check in when conditions are met

Check-in Token

Each event with check-in enabled has a checkInToken — a secret hex string used to gate check-in access. The token is:

Included in QR codes and check-in links (e.g. /check-in/:eventId/:token)
Required for anonymous flows — self-registrations and anonymous check-in endpoints validate the token
Not exposed to unauthenticated users except via the check-in URL (e.g. from QR scan)

Check-in Flows

1. Logged-in Self Check-in (no token)

Route: Event page → Check In button
Endpoint: POST /events/:eventId/check-in/self
Auth: Required (verifyToken)

User must be logged in
No token needed
Uses req.user.userId to find/create attendee
Validates event time and requireRegistration if set

2. Logged-in Token Check-in

Route: /check-in/:eventId/:token
Endpoint: POST /events/:eventId/check-in
Body: { token }
Auth: Optional (verifyTokenOptional)

User is logged in and has the token in the URL
Token validates access
Same logic as self check-in but with token validation

3. Anonymous Pick-Your-Registration

Route: /check-in/:eventId/:token (user not logged in)
Endpoints:

GET /events/:eventId/check-in/self-registrations?token=xxx — list registrations
GET /events/:eventId/check-in/registration/:formResponseId?token=xxx — form details
POST /events/:eventId/check-in/anonymous — check in by userId or formResponseId
Auth: None (token validates)

Flow:

User opens check-in link (from QR or event page) with token
Frontend fetches registrations via self-registrations
User searches by name/email and selects their registration
User can “View details” to see their full registration form (anonymous only)
User clicks “Check In” → POST /events/:eventId/check-in/anonymous with { token, formResponseId } or { token, userId }

Anonymous check-in is not locked to the browser. Users can register on one device and check in on another — they only need the token and to find their name in the list.

4. Manual Check-in (Organizer)

Endpoints:

POST /events/:eventId/check-in/:userId — check in logged-in attendee
POST /events/:eventId/check-in/by-form-response/:responseId — check in anonymous attendee

Auth: Required (verifyToken) + event management permission Organizers use the Event Dashboard Check-in tab to search and manually check in attendees.

Anonymous Registration

FormResponse Model

Anonymous registrations are stored as FormResponse documents with submittedBy: null:

{
  form: ObjectId,
  event: ObjectId,
  formSnapshot: Object,  // Form as it was when submitted
  submittedBy: null,    // null = anonymous
  guestName: String,
  guestEmail: String,
  answers: [ ... ],
  submittedAt: Date
}

Browser localStorage (anonymousRegistrationStorage)

The frontend uses meridian-anonymous-registrations in localStorage to track when the current browser has registered for an event without an account. Purpose:

Show “You are registered” on the event page
Verify with server that registration still exists (GET /events/:eventId/check-anonymous-registration?guestEmail=...)
Support “Add another registration” — allow multiple anonymous registrations per event from the same browser

Storage shape:

{
  [eventId]: {
    guestName: string,
    guestEmail: string,  // normalized (trim + lowercase)
    registeredAt: string,  // ISO date
    _v: number
  }
}

Key functions:

hasAnonymousRegistration(eventId) — whether this browser has a stored registration
getAnonymousRegistration(eventId) — get stored details
saveAnonymousRegistration(eventId, { guestName, guestEmail }) — save after successful registration
removeAnonymousRegistration(eventId) — clear when server says registration no longer exists
getAllAnonymousRegistrations() — for claim API

localStorage is browser-scoped. It does not gate check-in. Users can check in from any device with the token — the list comes from the server, not localStorage.

Claim Anonymous Registrations

When a user signs up or logs in, the frontend calls POST /claim-anonymous-registrations with { registrations: [ { eventId, guestEmail } ] }. For each matching anonymous FormResponse (same event, submittedBy: null, email match), the backend:

Sets submittedBy to the user’s ID
Updates guestName/guestEmail from the user account if the form collects them
Adds the user to event.attendees if not already present

This links previously anonymous registrations to the new account.

Anonymous Identifiers (Analytics)

Separate from event registration, the analytics platform uses an anonymous_id for tracking events before and after login:

Concept	Purpose	Storage
Analytics `anonymous_id`	Device-scoped persistent ID for analytics events (no PII)	Client (e.g. AsyncStorage, localStorage)
Anonymous FormResponse	Event registration without account (`submittedBy: null`)	Server (MongoDB)
localStorage registration	”This browser registered for this event”	Client (localStorage)

See Analytics Platform for the analytics envelope and anonymous_id usage.

API Reference

Public Check-in (token required, no auth)

Method	Endpoint	Description
GET	`/events/:eventId/check-in/self-registrations?token=xxx`	List registrations (logged-in + anonymous) for pick-your-registration
GET	`/events/:eventId/check-in/registration/:formResponseId?token=xxx`	Get form snapshot + answers for an anonymous registration
POST	`/events/:eventId/check-in/anonymous`	Check in by `{ token, formResponseId }` or `{ token, userId }`

Authenticated Check-in

Method	Endpoint	Description
POST	`/events/:eventId/check-in/self`	Self check-in (logged-in, no token)
POST	`/events/:eventId/check-in`	Token check-in (body: `{ token }`)
POST	`/events/:eventId/check-out`	Remove own check-in

Organizer / Management

Method	Endpoint	Description
POST	`/events/:eventId/check-in/enable`	Enable check-in
POST	`/events/:eventId/check-in/disable`	Disable check-in
PUT	`/events/:eventId/check-in/settings`	Update check-in settings
GET	`/events/:eventId/check-in/qr`	Get QR code for check-in
GET	`/events/:eventId/check-in/link`	Get check-in URL
GET	`/events/:eventId/check-in/attendees`	List checked-in attendees
POST	`/events/:eventId/check-in/:userId`	Manual check-in (logged-in)
POST	`/events/:eventId/check-in/by-form-response/:responseId`	Manual check-in (anonymous)

Anonymous Registration Verification

Method	Endpoint	Description
GET	`/events/:eventId/check-anonymous-registration?guestEmail=xxx`	Check if anonymous registration exists (for localStorage sync)
POST	`/claim-anonymous-registrations`	Claim anonymous registrations after sign-up (body: `{ registrations: [ { eventId, guestEmail } ] }`)

Frontend Components

Component	Location	Purpose
`EventCheckInButton`	`Meridian/frontend/src/components/EventCheckInButton`	Check-in button on event page; navigates with token for anonymous
`CheckInConfirmation`	`Meridian/frontend/src/pages/CheckIn`	Check-in page; handles token validation, anonymous pick UI, form details modal
`ManualCheckInModal`	`Meridian/frontend/.../EventCheckInTab`	Organizer manual check-in (search + select)
`RSVPButton` / `RSVPSection`	`Meridian/frontend/src/components`	Registration; uses `anonymousRegistrationStorage` for “registered” state and “Add another”

Event dashboard

Event management, readiness, and organizer tooling around the same events.

Event management API

REST paths for RSVPs, agendas, and org-event operations used by check-in flows.

Beacon events

Event lifecycle, approvals, and RSVP from the Beacon product lens.

Platform analytics

Event pipeline, envelope schema, and anonymous_id–friendly tracking.

Analytics collected events

Named events and properties emitted by web and mobile clients.

Atlas messaging

Announcements and anonymous recipients tied to event outreach.

Overview

Engineering

Server platform

Clients

Event Check-in & Anonymous Identifiers

Event Check-in & Anonymous Identifiers

Check-in System Overview

Logged-in self check-in

Token-based check-in

Anonymous pick-your-registration

Check-in Settings

Check-in Token

Check-in Flows

1. Logged-in Self Check-in (no token)

2. Logged-in Token Check-in

3. Anonymous Pick-Your-Registration

4. Manual Check-in (Organizer)

Anonymous Registration

FormResponse Model

Browser localStorage (anonymousRegistrationStorage)

Claim Anonymous Registrations

Anonymous Identifiers (Analytics)

API Reference

Public Check-in (token required, no auth)

Authenticated Check-in

Organizer / Management

Anonymous Registration Verification

Frontend Components

Event dashboard

Event management API

Beacon events

Platform analytics

Analytics collected events

Atlas messaging

​Event Check-in & Anonymous Identifiers

​Check-in System Overview

Logged-in self check-in

Token-based check-in

Anonymous pick-your-registration

​Check-in Settings

​Check-in Token

​Check-in Flows

​1. Logged-in Self Check-in (no token)

​2. Logged-in Token Check-in

​3. Anonymous Pick-Your-Registration

​4. Manual Check-in (Organizer)

​Anonymous Registration

​FormResponse Model

​Browser localStorage (anonymousRegistrationStorage)

​Claim Anonymous Registrations

​Anonymous Identifiers (Analytics)

​API Reference

​Public Check-in (token required, no auth)

​Authenticated Check-in

​Organizer / Management

​Anonymous Registration Verification

​Frontend Components

​Related pages

Event dashboard

Event management API

Beacon events

Platform analytics

Analytics collected events

Atlas messaging

Event Check-in & Anonymous Identifiers

Check-in System Overview

Check-in Settings

Check-in Token

Check-in Flows

1. Logged-in Self Check-in (no token)

2. Logged-in Token Check-in

3. Anonymous Pick-Your-Registration

4. Manual Check-in (Organizer)

Anonymous Registration

FormResponse Model

Browser localStorage (anonymousRegistrationStorage)

Claim Anonymous Registrations

Anonymous Identifiers (Analytics)

API Reference

Public Check-in (token required, no auth)

Authenticated Check-in

Organizer / Management

Anonymous Registration Verification

Frontend Components

Related pages