AsyncAPI channel · Starknet · Starknet WebSocket RPC API

starknet_subscribeNewHeads

Creates a WebSocket stream that fires notifications for new block headers. The client publishes a `starknet_subscribeNewHeads` request and receives a `subscription_id`; subsequent block header notifications are delivered via `starknet_subscriptionNewHeads` carrying the same `subscription_id`.

Open source AsyncAPI → All Starknet channels Starknet provider profile
Provider: Starknet AsyncAPI: v2.6.0 Spec: Starknet WebSocket RPC API Operations: 2 Messages: 5

Channel address

starknet_subscribeNewHeads

Operations

publish
subscribeNewHeads
Subscribe to new block headers.
onSubscribeNewHeadsResponse
Receive subscription id, header notifications, or reorg notifications for this stream.

Messages

SubscribeNewHeadsRequest
JSON-RPC request opening a new-headers subscription.
Content-Type: application/json
SubscriptionIdResponse
Returned by the server in response to any successful `starknet_subscribe*` request; the `result` is the assigned `subscription_id` which is echoed in every subsequent notification.
Content-Type: application/json
SubscriptionNewHeadsNotification
Server-pushed notification carrying a new block header.
Content-Type: application/json
SubscriptionReorgNotification
Server-pushed notification that the chain has reorganized. Can be emitted on subscriptions of type newHeads, Events, TransactionStatus, NewTransactionReceipts, and NewTransactions.
Content-Type: application/json
JsonRpcErrorResponse
Returned when a `starknet_subscribe*` or `starknet_unsubscribe` request fails. Error codes defined by the WebSocket spec include INVALID_SUBSCRIPTION_ID (66), TOO_MANY_ADDRESSES_IN_FILTER (67), and TO
Content-Type: application/json

About AsyncAPI

The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.

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