AsyncAPI channel · Kusama · Kusama JSON-RPC Subscription API

chain_subscribeFinalizedHeads

Emits a header only once a block is finalized by GRANDPA. This is the subscription that matters for anything financial — a block on the best chain can still be reorged away; a finalized block cannot. Unsubscribe with chain_unsubscribeFinalizedHeads. The British spelling chain_subscribeFinalisedHeads is also served as an alias.

Open source AsyncAPI → All Kusama channels Kusama provider profile
Provider: Kusama AsyncAPI: v3.0.0 Spec: Kusama JSON-RPC Subscription API Operations: 1 Messages: 1

Channel address

chain_subscribeFinalizedHeads

Operations

receive
receiveFinalizedHeads
Receive block headers only after GRANDPA finalization.

Messages

blockHeader
Block header
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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