The key whose value should be retrieved.
A promise that resolves to the stored value.
key is missing or is not a stringThis method can be used to subscribe to real-time updates for a specific key.
The provided callback function is executed whenever the value associated with the key is updated by any participant.
The key to observe for updates.
A function that handles value updates along with the ID of the participant who made the change.
key is missing, key is not a string, or callback is not a functionThis method can be used to store or update a value in the Realtime Store.
If the specified key already exists, its value is overwritten. Passing null as the value deletes the key from the store.
A unique identifier used to store the value.
The value to store. Pass null to delete the key.
key is missing, key is not a string, or value is neither a string nor nullThis method can be used to stop receiving updates for a previously registered observer.
Safe to call from cleanup paths: this method never rejects. An unknown, already-stopped, or missing observerId resolves as a no-op, and a failed server unsubscribe is recorded in telemetry rather than surfaced.
The unique observer ID returned by the observe() method.