AsyncAPI channel · QuickNode · QuickNode WebSocket Subscription API

ethereum/newHeads

Subscribe to new block headers on Ethereum (or any EVM chain) via `eth_subscribe` with the `newHeads` subscription type. The server returns a hex-encoded subscription id and then streams a notification for every new block header. Cancel with `eth_unsubscribe`.

Provider: QuickNode AsyncAPI: v2.6.0 Spec: QuickNode WebSocket Subscription API Operations: 2 Messages: 5

Channel address

ethereum/newHeads

Operations

publish
subscribeEthNewHeads
Send eth_subscribe / eth_unsubscribe for newHeads
receiveEthNewHeads
Receive subscription id and newHeads notifications

Messages

EthSubscribeNewHeadsRequest
Subscribe to new block headers
Content-Type: application/json
EthUnsubscribeRequest
Cancel an active eth_subscribe subscription
Content-Type: application/json
EthSubscribeResponse
Returned subscription id (hex string)
Content-Type: application/json
EthUnsubscribeResponse
eth_unsubscribe response
Content-Type: application/json
EthNewHeadsNotification
eth_subscription newHeads notification
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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