php - Why am I getting File Does Not Exist error on App Engine when it's there in Storage, Using Laravel-Excel -

running php on app engine, laravel 5.1.

the app failing on \excel::load($path); statement afterwards when @ app engine storage path file there. here code:

        $file = $file->move($destpath,$filename);          $path = $file->getpathname();         if (in_array($file->getextension(), ['xlsx', 'xlsm', 'xltx', 'xltm', 'xls', 'xlt'])){             $newfile = \excel::load($path); //fails here             $info = $newfile->store('csv', storage_path('imports'), true);             \file::delete($path);             $path = $info['full'];         } 

i tried putting sleep between file->move statement didn't have effect.

any suggestions appreciated.

since first posted here's we've tried.

1. we tried uploading spreadsheet directly (by passing $file->move) , loading that. didn't work.
2. on theory open office writing file wasn't compatible, tried file save using excel. didn't work.
3. on theory excel5 file didn't work, tried excel2007. didn't work.
4. tested simple fopen, fget, fseek. worked.

here's stack trace.

in excel2007.php line 82 @ phpexcel_reader_excel2007->canread('/base/data/home/apps/s~populous-2-0/20170914t111153.404103259874586280/gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx') in formatidentifier.php line 249 @ formatidentifier->canread('excel2007', '/base/data/home/apps/s~populous-2-0/20170914t111153.404103259874586280/gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx') in formatidentifier.php line 51 @ formatidentifier->getformatbyfile('/base/data/home/apps/s~populous-2-0/20170914t111153.404103259874586280/gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx') in laravelexcelreader.php line 1341 @ laravelexcelreader->_setformat() in laravelexcelreader.php line 777 @ laravelexcelreader->_init('gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx', null, false) in laravelexcelreader.php line 275 @ laravelexcelreader->load('gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx', null, false, null) in excel.php line 119 @ excel->load('gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx') in facade.php line 215 @ facade::__callstatic('load', array('gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx')) in staffcontroller.php line 173 @ excel::load('gs://populous-2-0.appspot.com/storage/imports/staff_import_17_1505402010.xlsx') in staffcontroller.php line 173