Realtime Store - JavaScript

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

note

This page uses the following asynchronous methods. Refer to their API reference for the errors each Promise may reject with, and handle these rejections appropriately based on your use case.

• setValue()
• getValue()
• observe()
• stopObserving()

setValue()

The setValue() 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 null 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 null.
• Throws an error if:
  • The key or value 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 | null)
  The string value to be stored. Pass null to delete the key.

Returns

• Promise<void>

Example

try {
  await meeting.realtimeStore.setValue("Blocked_Students", "[Halima,Rajan]");
  console.log("Data set successfully!");
} catch (error) {
  console.error("Failed to set data:", error);
}

---

getValue()

The getValue() 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 FAILED_TO_GET_VALUE if the key has not been set or if the request fails.

Parameters

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

Returns

• Promise<string> — The stored value for the given key.

Example

try {
  const value = await meeting.realtimeStore.getValue("Blocked_Students");
  console.log("Current value:", value);
} catch (error) {
  console.error("Failed to get data:", error);
}

---

observe()

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

Key Notes

• Returns an observerId which you can later use to stop observing.
• The callback 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.

• callback (function) Function triggered on each update. Receives:

  • value (string | null) → Updated value or null if deleted
  • updatedBy (string) → ID of the participant who made the update

Returns

• Promise<string> — Unique observer ID.

Example

try {
  const observerId = await meeting.realtimeStore.observe(
    "Blocked_Students",
    (value, updatedBy) => {
      console.log("Value updated:", value, "by", updatedBy);
    }
  );
} catch (error) {
  console.error("Failed to observe key:", error);
}

---

stopObserving()

Stops receiving updates for a specific observer ID.

Key Notes

• Should be called when the listener is no longer needed (e.g., component unmount).

Parameters

• observerId (string) The observer ID returned from observe().

Returns

• Promise<void>

Example

try {
  await meeting.realtimeStore.stopObserving(observerId);
  console.log("Stopped observing successfully!");
} catch (error) {
  console.error("Failed to stop observing:", error);
}

---

⚠️ Error Handling & Constraints

Property	Description
Error Handling	All RealtimeStore methods throw directly; wrap them in try...catch.
Payload Size	Maximum 1 KB per key.
Supported Type	Only string values are supported. Use null 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:

• setValue()
• getValue()
• observe()
• stopObserving()