Lifecycle hooks

SDK · 07

Both Axon and Dendrite mix in LifecycleHooks. The same three decorators are available on each.

Hook	Fires when
on_connect(fn)	Once, after this component finishes its own connect handshake. For an Axon, after the hosting Dendrite emits REGISTER; for a Dendrite, after synapse subscriptions are wired.
on_refresh(fn)	On each refresh event - a heartbeat tick, a REGISTER / DEREGISTER / HEARTBEAT observed via the registry mirror, or a manual `await component.refresh(reason=...)`. The handler receives a `RefreshEvent(reason, neuron_id, extra)`.
on_schedule(every_s=N)(fn)	Developer-supplied periodic task. Runs as a background coroutine every `every_s` seconds for the lifetime of the component.

async methodcomponent.refresh(*, reason='manual', neuron_id=None, extra=None) -> None

Manually fire on_refresh handlers with the supplied RefreshEvent. Use when your own code knows state has changed but the SDK can't detect it.

hooks.py

# 1. Announce on connect
@dendrite.on_connect
async def hello(d):
    snap = await d.registry_snapshot()
    log.info(f"Up on {d.namespace}: {len(snap)} known neurons")

# 2. React to refresh events (heartbeat / register / deregister / manual)
@dendrite.on_refresh
async def reconcile(d, event):
    if event.reason == "register":
        log.info("New peer: %s", event.neuron_id)

# 3. Periodic background task
@dendrite.on_schedule(every_s=30)
async def rollup(d):
    snap = await d.registry_snapshot(include_deregistered=True)
    publish_derived_view(snap)

# 4. Manual trigger
await dendrite.refresh(reason="manual", extra={"why": "side-channel update"})

Have a feature in mind?

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