Update

core/bitrix/modules/rest/lib/Internal/Integration/Market/Subscription.php

@@ -0,0 +1,61 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix\Rest\Internal\Integration\Market;
+
+use Bitrix\Main\Error;
+use Bitrix\Main\Loader;
+use Bitrix\Main\ModuleManager;
+use Bitrix\Main\Result;
+use Bitrix\Market\Subscription\Trial;
+
+class Subscription
+{
+	private bool $isModuleIncluded;
+
+	public function __construct()
+	{
+		$this->isModuleIncluded = Loader::includeModule('market');
+	}
+
+	public function activateDemo(): Result
+	{
+		$result = new Result();
+
+		if (
+			!$this->isModuleIncluded
+			|| !$this->isDemoAvailable()
+		)
+		{
+			return $result->addError(
+				new Error('Subscription is not available')
+			);
+		}
+
+		$res = Trial::activate();
+
+		if (isset($res['error']))
+		{
+			$error = new Error(
+				is_string($res['error']) ? $res['error'] : 'Unknown error',
+				isset($res['error_code']) && (is_string($res['error_code']) || is_int($res['error_code']))
+					? $res['error_code']
+					: null,
+			);
+
+			return $result->addError($error);
+		}
+
+		return $result->setData($res);
+	}
+
+	private function isDemoAvailable(): bool
+	{
+		return Trial::isAvailable()
+			&& (
+				!ModuleManager::isModuleInstalled('extranet')
+				|| (Loader::includeModule('extranet') && \CExtranet::IsIntranetUser())
+			);
+	}
+}

core/bitrix/modules/rest/lib/Internal/Request/Listener/ActivateDemoMarketListener.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Bitrix\Rest\Internal\Request\Listener;
+
+use Bitrix\Main\HttpRequest;
+
+class ActivateDemoMarketListener implements Listener
+{
+	protected const PARAM_NAME = 'activate_demo_market';
+
+	public function handle(HttpRequest $request): void
+	{
+		if ($request->getQuery(static::PARAM_NAME) === 'Y')
+		{
+			$subscription = new \Bitrix\Rest\Internal\Integration\Market\Subscription();
+			$subscription->activateDemo();
+		}
+	}
+}

core/bitrix/modules/rest/lib/Internal/Request/Listener/Listener.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace Bitrix\Rest\Internal\Request\Listener;
+
+use Bitrix\Main\HttpRequest;
+
+interface Listener
+{
+	public function handle(HttpRequest $request): void;
+}

core/bitrix/modules/rest/lib/Internal/Request/Listener/ListenerCollection.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Bitrix\Rest\Internal\Request\Listener;
+
+use Bitrix\Main\Application;
+use Bitrix\Main\HttpRequest;
+
+class ListenerCollection
+{
+	/** @var Listener[] */
+	private array $listeners = [];
+
+	public function addListener(Listener $listener): void
+	{
+		$this->listeners[] = $listener;
+	}
+
+	public function handleRequest(HttpRequest $request = null): void
+	{
+		$request ??= Application::getInstance()->getContext()->getRequest();
+
+		foreach ($this->listeners as $listener)
+		{
+			$listener->handle($request);
+		}
+	}
+}

core/bitrix/modules/rest/lib/Internal/Service/MemoryLimitChecker.php

@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Bitrix\Rest\Internal\Service;
+
+use Bitrix\Main\Config\Option;
+
+class MemoryLimitChecker
+{
+	public function __construct(
+		private readonly int $memoryLimit,
+		private readonly float $memoryRate,
+	) {
+	}
+
+	public static function createByDefault(): self
+	{
+		return new self(
+			self::memoryLimitFromPhpIniInMb(),
+			(float)Option::get('rest', 'memory_limit_rate', 0.9),
+		);
+	}
+
+	public function executeOnMemoryExcess(callable $callback): void
+	{
+		if ($this->memoryLimit <= 0 || $this->memoryRate <= 0 || $this->memoryRate > 1)
+		{
+			return;
+		}
+		
+		$memoryUsageMB = memory_get_usage() / (1024 * 1024);
+		$maxAllowedSizeMB = $this->memoryLimit * $this->memoryRate;
+
+		if ($memoryUsageMB > $maxAllowedSizeMB)
+		{
+			$callback($memoryUsageMB, $maxAllowedSizeMB);
+		}
+	}
+
+	private static function memoryLimitFromPhpIniInMb(): int
+	{
+		$memoryLimit = ini_get('memory_limit');
+		if ($memoryLimit === false)
+		{
+			return 0;
+		}
+
+		$unit = strtoupper(substr($memoryLimit, -1));
+		$value = (int)$memoryLimit;
+
+		return match ($unit)
+		{
+			'G' => $value * 1024,
+			'M' => $value,
+			'K' => (int)ceil($value / 1024),
+			default => (int)ceil((int)$memoryLimit / (1024 * 1024)),
+		};
+	}
+}