Warnings in PHP log during an export epub

[prolibre]

PHPePub is used by wallabag

During export articles in epub format i have :

Warnings in PHP log :

[Mon Nov 21 15:00:14.654739 2016] [:error] [pid 25654] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:00:14.655128 2016] [:error] [pid 25654] [client IP:PORT] PHP Warning:  is_file(): open_basedir restriction in effect. File(/var/www/heraut_eu/lou/www//) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/phpzip/phpzip/src/Zip/Core/AbstractZipArchive.php on line 368
[Mon Nov 21 15:00:14.655281 2016] [:error] [pid 25654] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:00:14.655396 2016] [:error] [pid 25654] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:15:21.146524 2016] [:error] [pid 25655] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:15:21.146917 2016] [:error] [pid 25655] [client IP:PORT] PHP Warning:  is_file(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/phpzip/phpzip/src/Zip/Core/AbstractZipArchive.php on line 368
[Mon Nov 21 15:15:21.147072 2016] [:error] [pid 25655] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:15:21.147171 2016] [:error] [pid 25655] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:30:08.834828 2016] [:error] [pid 28756] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:30:08.835217 2016] [:error] [pid 28756] [client IP:PORT] PHP Warning:  is_file(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/phpzip/phpzip/src/Zip/Core/AbstractZipArchive.php on line 368
[Mon Nov 21 15:30:08.835384 2016] [:error] [pid 28756] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941
[Mon Nov 21 15:30:08.835508 2016] [:error] [pid 28756] [client IP:PORT] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/) is not within the allowed path(s): (/DIR_ALLOWED) in /DIR_INSTALL_WALLABAG/vendor/grandt/phpepub/src/PHPePub/Core/EPub.php on line 941

/DIR_INSTALL_WALLABAG : the install directory of my wallabag instance
/DIR_ALLOWED : two directoy allowed in allowed_paths configuration ( php.ini )

I have open a ticket in wallabag : wallabag/wallabag#2631
but wallabad is not directly concerned.

thanks