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

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 an error if the key is missing or if the request fails.

Parameters

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

Returns

• Promise<string | null> — The stored value or null if there was a problem fetching the value.

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()