README

danog/loop 提供了一套强大的基于 amphp 的异步循环 API，用于定期或在需要时执行操作，类似于线程的后台循环。

安装

composer require danog/loop

API

• 基础
  • GenericLoop
  • PeriodicLoop
• 高级
  • Loop

Loop

类 - 示例

一个可以在后台（异步）运行 loop 函数中包含的代码的循环。
实现暂停和恢复功能，并且可以从外部或内部停止。

API

namespace danog\Loop;

abstract class Loop
{
    /**
     * Stop the loop.
     */
    public const STOP;
    /**
     * Pause the loop.
     */
    public const PAUSE;
    /**
     * Rerun the loop.
     */
    public const CONTINUE;

    /**
     * Loop body.
     *
     * The return value can be:
     * A number - the loop will be paused for the specified number of seconds
     * Loop::STOP - The loop will stop
     * Loop::PAUSE - The loop will pause forever (or until loop is `resume()`'d
     *                        from outside the loop)
     * Loop::CONTINUE - Return this if you want to rerun the loop immediately
     *
     * The loop can be stopped from the outside by using stop().
     * @return float|Loop::STOP|Loop::PAUSE|Loop::CONTINUE
     */
    abstract protected function loop(): ?float;

    /**
     * Loop name, useful for logging.
     */
    abstract public function __toString(): string;

    /**
     * Start the loop.
     *
     * Returns false if the loop is already running.
     */
    public function start(): bool;
    /**
     * Resume the loop.
     *
     * If resume is called multiple times, and the event loop hasn't resumed the loop yet,
     * the loop will be resumed only once, not N times for every call.
     *
     * @param bool $postpone If true, multiple resumes will postpone the resuming to the end of the callback queue instead of leaving its position unchanged.
     *
     * @return bool Returns false if the loop is not paused.
     */
    public function resume(bool $postpone = false): bool;
    /**
     * Stops loop.
     *
     * Returns false if the loop is not running.
     */
    public function stop(): bool;

    /**
     * Check whether loop is running.
     */
    public function isRunning(): bool;
    /**
     * Check whether loop is paused.
     */
    public function isPaused(): bool;

    /**
     * Report pause, can be overriden for logging.
     *
     * @param float $timeout Pause duration, 0 = forever
     */
    protected function reportPause(float $timeout): void;

    /**
     * Signal that loop was started.
     */
    protected function startedLoop(): void;
    /**
     * Signal that loop has exited.
     */
    protected function exitedLoop(): void;
}

GenericLoop

类 - 示例

如果你想要一个更简单的方式来使用 Loop，你可以使用 GenericLoop。

namespace danog\Loop;

class GenericLoop extends Loop
{
    /**
     * Constructor.
     *
     * The return value of the callable can be:
     * * A number - the loop will be paused for the specified number of seconds
     * * GenericLoop::STOP - The loop will stop
     * * GenericLoop::PAUSE - The loop will pause forever (or until loop is `resume()`'d
     *                        from outside the loop)
     * * GenericLoop::CONTINUE - Return this if you want to rerun the loop immediately
     *
     * If the callable does not return anything,
     * the loop will behave is if GenericLoop::PAUSE was returned.
     *
     * The loop can be stopped from the outside by using stop().
     *
     * @param callable(static):?float $callable Callable to run
     * @param string   $name     Loop name
     */
    public function __construct(callable $callable, private string $name);
    /**
     * Get loop name, provided to constructor.
     */
    public function __toString(): string;
}

PeriodicLoop

类 - 示例

如果你只想每 N 秒执行一次操作，PeriodicLoop 是最佳选择。

namespace danog\Loop;

class PeriodicLoop extends GenericLoop
{
    /**
     * Constructor.
     *
     * Runs a callback at a periodic interval.
     *
     * The loop can be stopped from the outside by calling stop()
     * and from the inside by returning `true`.
     *
     * @param callable(static):bool $callback Callable to run
     * @param string   $name     Loop name
     * @param ?float   $interval Loop interval; if null, pauses indefinitely or until `resume()` is called.
     */
    public function __construct(callable $callback, string $name, ?float $interval)
    /**
     * Get name of the loop, passed to the constructor.
     *
     * @return string
     */
    public function __toString(): string;
}