kiri-http-server/Abstracts/ReloadWorkers.php

<?php

namespace Kiri\Server\Abstracts;

use Kiri\Server\ServerInterface;
use Swoole\Process;

trait ReloadWorkers
{

	private static ?int $cachedMasterPid = null;

	/**
	 * @return void
	 */
	private function reloadWorkers(): bool
	{
		if ($this->reloadByServerInstance()) {
			return true;
		}

		$pid = $this->getMasterPid();
		if ($pid === null) {
			return false;
		}

		return Process::kill($pid, SIGUSR1);
	}

	private function reloadByServerInstance(): bool
	{
		try {
			$server =  di(ServerInterface::class) ;
			return $server->reload() !== false;
		} catch (\Throwable) {
			return false;
		}
	}

	private function getMasterPid(): ?int
	{
		if (self::$cachedMasterPid !== null && $this->isCachedMasterPid(self::$cachedMasterPid)) {
			return self::$cachedMasterPid;
		}

		self::$cachedMasterPid = null;

		$pidFilePid = $this->getPidFileMasterPid();
		if ($pidFilePid !== null) {
			self::$cachedMasterPid = $pidFilePid;
			return $pidFilePid;
		}
		$processes  = $this->listProcesses();
		$candidates = [];

		foreach ($processes as $process) {
			if ($this->isMasterProcessCommand($process['command'])) {
				$candidates[] = (int)$process['pid'];
			}
		}

		foreach ($candidates
		         |> array_filter(...)
		         |> array_unique(...)
		         |> array_values(...) as $pid) {
			if ($this->isProcessAlive($pid) && $this->isMasterPid($pid, $processes)) {
				self::$cachedMasterPid = $pid;
				return $pid;
			}
		}

		return null;
	}

	private function isCachedMasterPid(int $pid): bool
	{
		if (!$this->isProcessAlive($pid)) {
			return false;
		}

		$pidFilePid = $this->readPidFile();
		if ($pidFilePid === $pid && $this->isSameAppProcess($pid)) {
			return true;
		}

		$command = $this->readProcessCommand($pid);
		return $command !== '' && $this->isMasterProcessCommand($command) && $this->isSameAppProcess($pid);
	}

	private function getPidFileMasterPid(): ?int
	{
		$pid = $this->readPidFile();
		if ($pid === null || !$this->isProcessAlive($pid) || !$this->isSameAppProcess($pid)) {
			return null;
		}

		return $pid;
	}

	private function readPidFile(): ?int
	{
		$pidFile = function_exists('storage') ? storage('.swoole.pid') : '';
		if ($pidFile === '' || !is_file($pidFile)) {
			return null;
		}

		$pid = (int)trim((string)file_get_contents($pidFile));
		return $pid > 1 ? $pid : null;
	}

	private function readProcessCommand(int $pid): string
	{
		$cmdline = @file_get_contents('/proc/' . $pid . '/cmdline');
		if (is_string($cmdline) && $cmdline !== '') {
			return trim(str_replace("\0", ' ', $cmdline));
		}

		return '';
	}

	private function isMasterPid(int $pid, array $processes): bool
	{
		foreach ($processes as $process) {
			if ((int)$process['pid'] === $pid) {
				return $this->isMasterProcessCommand($process['command']) && $this->isSameAppProcess($pid);
			}
		}

		return false;
	}
	private function listProcesses(): array
	{
		$lines = [];
		exec('ps -eo pid=,ppid=,args= 2>/dev/null', $lines);

		$processes = [];
		foreach ($lines as $line) {
			$line = trim($line);
			if ($line === '') {
				continue;
			}

			$parts = preg_split('/\s+/', $line, 3);
			if (count($parts) < 3) {
				continue;
			}

			$processes[] = [
				'pid'     => (int)$parts[0],
				'ppid'    => (int)$parts[1],
				'command' => $parts[2],
			];
		}

		return $processes;
	}
}