Realtime Store - iOS

The Realtime Store allows you to store, update, retrieve, and observe custom key-value data within a meeting — in real time. It acts as a shared data layer across all connected participants, ensuring synchronized states throughout the session.

This is particularly useful for collaborative or stateful meeting experiences such as:

• Pinned messages and flags
• Moderation data (e.g., blocked users)
• Collaborative notes or polls

set()

The set() method is used to store or update data in the RealtimeStore. If a key already exists, it will be overwritten with the new value. Passing nil as the value deletes the key.

Key Notes

• Supports String values only.
• Each key can store up to 1 KB of data.
• A maximum of 100 keys are allowed per session.
• Deletion is performed by setting the value to nil.
• Throws an error if:
  • The key is missing or not of type String.
  • The request fails.
  • The session exceeds the 100-key limit.

Parameters

• key (String)
  The unique key to store the data under.

• value (String?)
  The string value to be stored. Pass nil to delete the key.

Example

let REALTIME_STORE_KEY = "Blocked_Students"
Task {
    do {
        try await meeting.realtimeStore.set(key: REALTIME_STORE_KEY, value: "[Deep,Lily]")
        print("Data set successfully!")
    } catch {
        print("Failed to set data: \(error.localizedDescription)")
    }
}

---

get()

The get() method retrieves the current value associated with a given key.

Key Notes

• Returns the current string value for the given key.
• Useful for fetching shared state when joining a meeting or reloading a view.
• Throws an error if the key is missing or if the request fails.

Parameters

• key (String) The key whose value you want to retrieve.

Returns

• String? — The stored value or nil if the key does not exist. The method throws an error on failure.

Example

let REALTIME_STORE_KEY = "Blocked_Students"
Task {
    do {
        let value = try await meeting.realtimeStore.get(key: REALTIME_STORE_KEY)
        let displayValue = value ?? "nil (key not found)"
        print("Current value: \(displayValue)")
    } catch {
        print("Failed to get data: \(error.localizedDescription)")
    }
}

---

observe()

The observe() method subscribes to real-time updates for a given key. When the key’s value changes, a delegate method on your listener is automatically triggered for all connected participants.

Key Notes

• You register a listener object that conforms to the RealtimeStoreListener protocol.
• The delegate method receives the new value and information about who updated it.
• Ideal for syncing live data like timers, shared notes, or agendas.

Parameters

• key (String) The key to observe.

• forListener (RealtimeStoreListener) An object that conforms to the RealtimeStoreListener protocol to receive updates.

Example

First, conform to the RealtimeStoreListener protocol:

extension MeetingViewController: RealtimeStoreListener {
    func onValueChanged(key: String, value: String?, updatedBy: String) {
        print("RealtimeStore Value Changed - Key: \(key), Value: \(value ?? "nil"), UpdatedBy: \(updatedBy)")
    }
}

Then, start observing:

let REALTIME_STORE_KEY = "Blocked_Students"
Task {
    do {
        try await meeting.realtimeStore.observe(key: REALTIME_STORE_KEY, forListener: self)
        print("Started observing key successfully!")
    } catch {
        print("Failed to observe key: \(error.localizedDescription)")
    }
}

---

stopObserving()

Stops receiving updates for a specific key and listener combination.

Key Notes

• Should be called when the listener is no longer needed (e.g., when the view controller is deallocated).

Parameters

• key (String) The key you want to stop observing.

• forListener (RealtimeStoreListener) The listener that should stop receiving updates.

Example

let REALTIME_STORE_KEY = "Blocked_Students"
Task {
    do {
        try await meeting.realtimeStore.stopObserving(key: REALTIME_STORE_KEY, forListener: self)
        print("Stopped observing successfully!")
    } catch {
        print("Failed to stop observing: \(error.localizedDescription)")
    }
}

---

Error Handling & Constraints

Property	Description
Error Handling	All RealtimeStore methods are async throws; wrap them in do-try-catch.
Payload Size	Maximum 1 KB per key.
Supported Type	Only String values are supported. Use nil to delete key.
Concurrency	The latest write overwrites previous values (last write wins)
Key Limit	A maximum of 100 keys are allowed in a single session.

API Reference

The API references for all the methods utilized in this guide are provided below:

• set()
• get()
• observe()
• stopObserving()