The function apache_request_headers, doesn't exist in FCGI PHP-FPM

Use this patch : https://gist.github.com/rmpel/11583cfddfcc9705578428e3a2ee3dc1

<?php
// Drop-in replacement for apache_request_headers() when it's not available

if ( ! function_exists( 'apache_request_headers' ) ) {
    function apache_request_headers() {
        static $arrHttpHeaders;
        if ( ! $arrHttpHeaders ) {

            // Based on: http://www.iana.org/assignments/message-headers/message-headers.xml#perm-headers
            $arrCasedHeaders = array(
                // HTTP
                'Dasl'             => 'DASL',
                'Dav'              => 'DAV',
                'Etag'             => 'ETag',
                'Mime-Version'     => 'MIME-Version',
                'Slug'             => 'SLUG',
                'Te'               => 'TE',
                'Www-Authenticate' => 'WWW-Authenticate',
                // MIME
                'Content-Md5'      => 'Content-MD5',
                'Content-Id'       => 'Content-ID',
                'Content-Features' => 'Content-features',
            );
            $arrHttpHeaders  = array();

            foreach ( $_SERVER as $strKey => $mixValue ) {
                if ( 'HTTP_' !== substr( $strKey, 0, 5 ) ) {
                    continue;
                }

                $strHeaderKey = strtolower( substr( $strKey, 5 ) );

                if ( 0 < substr_count( $strHeaderKey, '_' ) ) {
                    $arrHeaderKey = explode( '_', $strHeaderKey );
                    $arrHeaderKey = array_map( 'ucfirst', $arrHeaderKey );
                    $strHeaderKey = implode( '-', $arrHeaderKey );
                } else {
                    $strHeaderKey = ucfirst( $strHeaderKey );
                }

                if ( array_key_exists( $strHeaderKey, $arrCasedHeaders ) ) {
                    $strHeaderKey = $arrCasedHeaders[ $strHeaderKey ];
                }

                $arrHttpHeaders[ $strHeaderKey ] = $mixValue;
            }

            /** in case you need authorization and your hosting provider has not fixed this for you:
             * VHOST-Config:
             * FastCgiExternalServer line needs    -pass-header Authorization
             *
             * .htaccess or VHOST-config file needs:
             * SetEnvIf Authorization "(.*)" HTTP_AUTHORIZATION=$1
             * to add the Authorization header to the environment for further processing
             */
            if ( ! empty( $arrHttpHeaders['Authorization'] ) ) {
                // in case of Authorization, but the values not propagated properly, do so :)
                if ( ! isset( $_SERVER['PHP_AUTH_USER'] ) ) {
                    list( $_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW'] ) = explode( ':', base64_decode( substr( $_SERVER['HTTP_AUTHORIZATION'], 6 ) ) );
                }
            }
        }

        return $arrHttpHeaders;
    }

    // execute now so other scripts have little chance to taint the information in $_SERVER
    // the data is cached, so multiple retrievals of the headers will not cause further impact on performance.
    apache_request_headers();
}