TelemetryBootstrap

Owns the telemetry lifecycle for a process: build the providers once, flush at each request boundary, and shut down on exit.

Called unconditionally from Kernel::bootstrap() — this class decides whether there is anything to do, so callers never need a feature-flag check of their own.

Construction is delegated: TelemetryConfig resolves the settings, TelemetryExporterFactory builds the exporters, and TelemetryProviderFactory assembles the providers around them. What remains here is the part that genuinely has to be process-wide — “configured once”, the registered shutdown function, and the handles the registry hands out.

Every path that can fail — telemetry disabled, the open-telemetry/sdk package not installed, a bad exporter or endpoint configuration — degrades to “telemetry stays off” rather than throwing. It is not a hard dependency.

Synopsis

final class TelemetryBootstrap

Source	TelemetryBootstrap.php

Methods

Method	Description
configureFromConfig(): bool	Build the providers from config.
flushAfterRequest(): void	Force-flush the active providers.
inMemoryMetricExporter(): ?InMemoryExporter	The in-memory metric exporter, when telemetry.exporter = none was used.
inMemorySpanExporter(): ?InMemoryExporter	The in-memory span exporter, when telemetry.exporter = none was used.
reset(): void	Reset all bootstrap and registry state, for test isolation or to simulate a fresh worker.
shutdown(): void	Final flush and shutdown.

configureFromConfig()

public static function configureFromConfig(): bool

Build the providers from config.

Idempotent: a second call (a second Kernel::bootstrap() in the same process) is a no-op that reports whether a real provider is already active. Call TelemetryBootstrap::reset() first to force a rebuild, for test isolation or to simulate a fresh worker.

Returns bool — True if a real, usable provider is now wired up.

flushAfterRequest()

public static function flushAfterRequest(): void

Force-flush the active providers.

Called at every worker request boundary (the Kernel’s post-request reset closure) so each request’s spans and metrics are exported without tearing the provider down. A no-op when telemetry is not configured.

inMemoryMetricExporter()

public static function inMemoryMetricExporter(): ?InMemoryExporter

The in-memory metric exporter, when telemetry.exporter = none was used.

For tests.

Returns ?``InMemoryExporter

inMemorySpanExporter()

public static function inMemorySpanExporter(): ?InMemoryExporter

The in-memory span exporter, when telemetry.exporter = none was used.

For tests.

Returns ?``InMemoryExporter

reset()

public static function reset(): void

Reset all bootstrap and registry state, for test isolation or to simulate a fresh worker.

Not used on the request path.

Cannot un-register a previously scheduled register_shutdown_function callback, and does not need to: that callback re-reads TraceRegistry when the process actually exits, so it is a safe no-op once this call has cleared the provider.

shutdown()

public static function shutdown(): void

Final flush and shutdown.

Registered once through register_shutdown_function, so single-shot mode (no persistent worker loop, no per-request reset closure) still exports its one request’s telemetry before the process exits, and worker mode gets a last-chance flush when the worker terminates.