s the filename if the request is WebP compatible
	 *
	 * @since 3.4
	 *
	 * @param string $filename Cache filename.
	 * @return string
	 */
	private function maybe_webp_filename( $filename ) {
		if ( ! $this->config->get_config( 'cache_webp' ) ) {
			return $filename;
		}

		/**
		 * Force WP Rocket to disable its webp cache.
		 *
		 * @since  3.4
		 *
		 * @param bool $disable_webp_cache Set to true to disable the webp cache.
		 */
		$disable_webp_cache = apply_filters( 'rocket_disable_webp_cache', false );

		if ( $disable_webp_cache ) {
			return $filename;
		}

		if ( ! $this->is_browser_webp_compatible() ) {
			return $filename;
		}

		return $filename . '-webp';
	}

	/**
	 * Checks if the browser is WebP compatible
	 *
	 * @since 3.12.6
	 *
	 * @return bool
	 */
	private function is_browser_webp_compatible(): bool {
		// Only to supporting browsers.
		$http_accept = $this->config->get_server_input( 'HTTP_ACCEPT', '' );

		if (
			empty( $http_accept )
			&&
			function_exists( 'apache_request_headers' )
		) {
			$headers     = apache_request_headers();
			$http_accept = isset( $headers['Accept'] ) ? $headers['Accept'] : '';
		}

		if (
			! empty( $http_accept )
			&&
			false !== strpos( $http_accept, 'webp' )
		) {
			return true;
		}

		return $this->is_user_agent_compatible();
	}

	/**
	 * Check the User Agent if the Accept headers is missing the WebP info
	 *
	 * @since 3.12.6
	 *
	 * @return bool
	 */
	private function is_user_agent_compatible(): bool {
		$user_agent = $this->config->get_server_input( 'HTTP_USER_AGENT' );

		if ( empty( $user_agent ) ) {
			return false;
		}

		if ( preg_match( '#Firefox/(?<version>[0-9]{2,})#i', $user_agent, $matches ) ) {
			if ( 66 >= (int) $matches['version'] ) {
				return false;
			}
		}

		if ( preg_match( '#(?:iPad|iPhone)(.*)Version/(?<version>[0-9]{2,})#i', $user_agent, $matches ) ) {
			if ( 14 > (int) $matches['version'] ) {
				return false;
			}

			return true;
		}

		if ( preg_match( '#Version/(?<version>[0-9]{2,})(?:.*)Safari#i', $user_agent, $matches ) ) {
			if ( 16 > (int) $matches['version'] ) {
				return false;
			}
		}

		return true;
	}

	/**
	 * Modifies the filename if dynamic cookies are set
	 *
	 * @param string $filename Cache filename.
	 * @param array  $cookies  Cookies for the request.
	 * @return string
	 */
	private function maybe_dynamic_cookies_filename( $filename, $cookies ) {
		$cache_dynamic_cookies = $this->config->get_config( 'cache_dynamic_cookies' );

		if ( ! $cache_dynamic_cookies ) {
			return $filename;
		}

		foreach ( $cache_dynamic_cookies as $key => $cookie_name ) {
			if ( is_array( $cookie_name ) ) {
				if ( isset( $_COOKIE[ $key ] ) ) {
					foreach ( $cookie_name as $cookie_key ) {
						if ( '' !== $cookies[ $key ][ $cookie_key ] ) {
							$cache_key = $cookies[ $key ][ $cookie_key ];
							$cache_key = preg_replace( '/[^a-z0-9_\-]/i', '-', $cache_key );
							$filename .= '-' . $cache_key;
						}
					}
				}
				continue;
			}

			if ( isset( $cookies[ $cookie_name ] ) && '' !== $cookies[ $cookie_name ] ) {
				$cache_key = $cookies[ $cookie_name ];
				$cache_key = preg_replace( '/[^a-z0-9_\-]/i', '-', $cache_key );
				$filename .= '-' . $cache_key;
			}
		}

		return $filename;
	}

	/**
	 * Force lowercase on encoded url strings from different alphabets to prevent issues on some hostings.
	 *
	 * @since  3.3
	 *
	 * @param  array $matches Cache path.
	 * @return string         Cache path in lowercase.
	 */
	protected function reset_lowercase( $matches ) {
		return strtolower( $matches[0] );
	}

	/**
	 * Sanitizes a string username.
	 *
	 * @param string $user String username.
	 *
	 * @return string
	 */
	private function sanitize_user( string $user = '' ): string {
		return strtolower( rawurlencode( $user ) );
	}

	/**
	 * Check if permalink structure and url match.
	 *
	 * @return bool
	 */
	private function maybe_allow_wp_redirect(): bool {

		$exclusions = implode( '|', $this->wp_redirect_exclusions );

		// Return early for excluded urls.
		if ( preg_match( '#' . $exclusions . '#', $this->tests->get_request_uri_base() )
		) {
			return false;
		}

		$permalink_structure = $this->config->get_config( 'permalink_structure' );

		// Last character of permalink.
		$permalink_last_char = '/' !== substr( $permalink_structure, -1 ) ? '' : '/';

		// Request uri without protocol & domain name.
		$request_uri = $this->tests->get_request_uri_base();

		// Last character of request uri.
		$request_uri_last_char = '/' !== substr( $request_uri, -1 ) ? '' : '/';

		// In cases where we have the home with a trailng slash (visible or invisible)
		// and permalink is without trailing slash.
		if ( '' === $permalink_last_char ) {
			// Check for root installation.
			$request_uri_last_char = '/' === $request_uri ? '' : $request_uri_last_char;

			/**
			 * Check for subdir installation.
			 * Use config file name to get home request_uri.
			 */
			$home = str_replace( $this->config->get_host(), '', basename( $this->config->get_config_file_path()['path'] ) );
			$home = str_replace( '.', '/', str_replace( '.php', '', $home ) );

			if ( '/' !== $request_uri && rtrim( $request_uri, '/' ) === $home ) {
				$request_uri_last_char = '';
			}
		}

		return $permalink_last_char !== $request_uri_last_char;
	}
}
<!DOCTYPE html>
<html dir='rtl'>
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
	<meta name="viewport" content="width=device-width">
			<title>خطای پایگاه‌داده</title>
	<style type="text/css">
		html {
			background: #f1f1f1;
		}
		body {
			background: #fff;
			border: 1px solid #ccd0d4;
			color: #444;
			font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
			margin: 2em auto;
			padding: 1em 2em;
			max-width: 700px;
			-webkit-box-shadow: 0 1px 1px rgba(0, 0, 0, .04);
			box-shadow: 0 1px 1px rgba(0, 0, 0, .04);
		}
		h1 {
			border-bottom: 1px solid #dadada;
			clear: both;
			color: #666;
			font-size: 24px;
			margin: 30px 0 0 0;
			padding: 0;
			padding-bottom: 7px;
		}
		#error-page {
			margin-top: 50px;
		}
		#error-page p,
		#error-page .wp-die-message {
			font-size: 14px;
			line-height: 1.5;
			margin: 25px 0 20px;
		}
		#error-page code {
			font-family: Consolas, Monaco, monospace;
		}
		ul li {
			margin-bottom: 10px;
			font-size: 14px ;
		}
		a {
			color: #2271b1;
		}
		a:hover,
		a:active {
			color: #135e96;
		}
		a:focus {
			color: #043959;
			box-shadow: 0 0 0 2px #2271b1;
			outline: 2px solid transparent;
		}
		.button {
			background: #f3f5f6;
			border: 1px solid #016087;
			color: #016087;
			display: inline-block;
			text-decoration: none;
			font-size: 13px;
			line-height: 2;
			height: 28px;
			margin: 0;
			padding: 0 10px 1px;
			cursor: pointer;
			-webkit-border-radius: 3px;
			-webkit-appearance: none;
			border-radius: 3px;
			white-space: nowrap;
			-webkit-box-sizing: border-box;
			-moz-box-sizing:    border-box;
			box-sizing:         border-box;

			vertical-align: top;
		}

		.button.button-large {
			line-height: 2.30769231;
			min-height: 32px;
			padding: 0 12px;
		}

		.button:hover,
		.button:focus {
			background: #f1f1f1;
		}

		.button:focus {
			background: #f3f5f6;
			border-color: #007cba;
			-webkit-box-shadow: 0 0 0 1px #007cba;
			box-shadow: 0 0 0 1px #007cba;
			color: #016087;
			outline: 2px solid transparent;
			outline-offset: 0;
		}

		.button:active {
			background: #f3f5f6;
			border-color: #7e8993;
			-webkit-box-shadow: none;
			box-shadow: none;
		}

		body { font-family: Tahoma, Arial; }	</style>
</head>
<body id="error-page">
	<div class="wp-die-message"><h1>خطا در برقراری ارتباط با پایگاه‌داده</h1></div></body>
</html>