Python lifecycle

asyncio maker groups, explicit construction phases, source-last start, and deadline-aware shutdown.

When to use

Use this page when implementing maker hooks, owning resources, or diagnosing startup and shutdown.

custom_makers_init runs once before infrastructure and function creation.
_MakerGroup uses asyncio.gather, cancels its context, and raises the first error.
build_stream_graph precedes bind_transports; runtime start activates Sources last.
stop_service bounds Context once, calls on_stop, then runtime stop with the remaining deadline.

ConfigurationLoad graph configResolve typed service, stream, connector, and endpoint settings.

Factories_initialize_makersInstall defaults, then run custom_makers_init, custom_functions_init, and on_start.

ConstructionInvoke makers onceCreate infrastructure and long-lived functions in parallel.

GraphBuild and bindConstruct streams, callers, endpoint consumers, and transports.

StartOpen admission lastStart dependencies and Sinks before Sources and servers.

SignalStop requestedCreate one deadline from shutdownTimeout.

AdmissionListeners and SourcesReject new root work and drain accepted calls.

GraphNested workKeep pools, storage, Sinks, and clients alive.

ResourcesPools, storage, SinksRelease graph dependencies in safe order.

TelemetryFlush and releaseMetrics, traces, and logs stop last.

Generated extension points and runtime-owned lifecycle boundaries.

PropertyTypeDescription

custom_makers_initasync hook

Mutates generated makers once.

initialize_infrastructuregenerated

Creates servers, clients, and infrastructure.

initialize_functionsgenerated

Runs function makers concurrently.

on_start / on_stopasync hooks

Run around runtime activation and drain.

run_shutdown_operationsruntime

Uses only the remaining shared deadline.

configure -> make once -> bind -> start -> admit -> drain -> stop