AsyncAPI channel · Optimism · Optimism (OP Stack) WebSocket JSON-RPC API

eth_subscribe.syncing

Subscription that emits when the node enters or exits sync. The notification is either `false` (synced) or a `SyncStatus` object describing progress. Behaviour matches upstream go-ethereum / op-geth.

Open source AsyncAPI → All Optimism channels Optimism provider profile
Provider: Optimism AsyncAPI: v2.6.0 Spec: Optimism (OP Stack) WebSocket JSON-RPC API Operations: 2 Messages: 3

Channel address

eth_subscribe.syncing

Operations

publish
subscribeSyncing
Subscribe to sync-status changes (`eth_subscribe("syncing")`).
onSyncing
Receive sync-status change notifications.

Messages

SubscribeSyncingRequest
JSON-RPC request to subscribe to sync status changes.
Content-Type: application/json
SubscribeResponse
JSON-RPC response containing the subscription id.
Content-Type: application/json
SyncingNotification
Notification carrying the current sync status.
Content-Type: application/json

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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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