ClockInterface

The one seam every direct time()/microtime()/new DateTime() call site in core is meant to go through instead.

Extends ClockInterface — whose single now() method is the wall-clock reading most callers actually want — with the two reads the timing- and expiry-sensitive code in this codebase needs and PSR-Clock does not provide:

• ClockInterface::unixTimestamp() and ClockInterface::microtime() are wall-clock, exactly like time()/microtime(true), for anything that stores or compares an epoch-relative expiry (a session’s idle timeout, a cache TTL, a cookie’s Expires). - ClockInterface::monotonic() is deliberately not wall-clock: it never steps backwards on an NTP correction or a VM clock resync, which is what a duration measurement (a request’s execution time, a connection’s idle check) actually needs. Mixing the two up is the class of bug documented on SessionManager’s resolveRedirect().

A test swaps in FrozenClock or OffsetClock; production gets SystemClock.

Synopsis

interface ClockInterface extends ClockInterface

Implements	ClockInterface
Implemented by	FrozenClock, OffsetClock, SystemClock
Source	Support/Clock/ClockInterface.php

Methods

Method	Description
microtime(): float	Wall-clock Unix timestamp with microsecond precision.
monotonic(): float	Seconds on a monotonic clock: immune to wall-clock steps, so only ever meaningful as the difference between two readings.
now(): DateTimeImmutable	The current wall-clock time.
unixTimestamp(): int	Wall-clock Unix timestamp in whole seconds.

microtime()

abstract public function microtime(): float

Wall-clock Unix timestamp with microsecond precision.

Replaces a direct microtime(true) call.

Returns float

monotonic()

abstract public function monotonic(): float

Seconds on a monotonic clock: immune to wall-clock steps, so only ever meaningful as the difference between two readings.

Replaces a direct hrtime(true) call (or a microtime(true) one used for a duration rather than a point in time).

Returns float

now()

abstract public function now(): DateTimeImmutable

The current wall-clock time.

Returns DateTimeImmutable

unixTimestamp()

abstract public function unixTimestamp(): int

Wall-clock Unix timestamp in whole seconds.

Replaces a direct time() call.

Returns int