streamMempoolCleanup

Subscribe to real-time mempool cleanup events. Get notified when the node removes stale unconfirmed transactions from its database, allowing apps to refresh or reload components for consistency. Powered by SSE for low-latency global notifications.

sequenceDiagram
    participant C as Client
    participant S as Server
    C->>S: streamMempoolCleanup(callbacks)
    S-->>C: SSE Connected (Promise resolves)
    Note over C,S: Mempool cleanup triggers
    S->>C: onMessage({type: 'cleanup', staleTxIds, revs}) // Deletions
    C->>S: unsubscribe() // Closes SSE

Type

streamMempoolCleanup(
  onMessage: (event: { revs: string[] }) => void,
  onError?: (error: Event) => void,
): Promise<() => void>

Parameters

onMessage

The function to call when a mempool cleanup event occurs. The callback receives an object containing:

• revs: Array of revisions (e.g., :) affected by the cleanup.

onError (optional)

A callback invoked when an error occurs on the SSE connection, such as network interruptions or parsing failures. It receives a standard browser Event object (e.g., with type: 'error' for connection issues).

For reconnection strategies, consider exponential backoff in your handler. See the MDN SSE error handling guide for more details.

Return Value

A promise that resolves to a cleanup function once the SSE connection is established. Calling the function closes the connection and stops updates.

Description

The streamMempoolCleanup method enables real-time notifications via Server-Sent Events (SSEs) for mempool cleanups. It opens a global SSE connection to the server and invokes the provided callback whenever the node performs a cleanup, removing stale unconfirmed transactions (those in the DB but not in the current mempool).

Tips

• Reconnection: SSEs can drop on network hiccups—use onError for exponential backoff retries.
• Global Scope: No filters; receives all cleanup events—ideal for app-wide refreshes.
• Performance: Limit concurrent streams; each opens a dedicated SSE.
• Cleanup Best Practice: Always invoke the returned function in hooks like React's useEffect return.