Export is empty when processing the queue vde_drush_queue by drush (or cron).
You may need to run this queue manually if previous export finished with out-of-memory error.
1) Create View with "Access: Role Administrator"
2) run drush command
drush vde_drush:views-data-export view_id display_id /filepath/export.csv --yes
3) after command will fail with "Fatal error: Allowed memory size" run
drush queue-run vde_drush_queue
AR: exported file will not be updated.
ER: new lines should be added to previously created export file.
The issue is with permissions. When we run drush command we switch user account to uid 1.
But on queue processing user is anonymous and that's why view returns no results.
To be honest, I dont like the situation when drush command fails with out of memory error.
As a solution we should not process queue items in vde_drush:views-data-export if export has more than X results. maybe > 10000.
New command could be created to create queue items only and then developer need to run script like this
for i in {1..100}; do drush queue-run vde_drush_queue --items-limit=10 ;done
to have all items in export.
Needs review
2.1
Code