Loris image server deployment for ARCHE

Important files

• root/loris.conf, especially the section with the resolver settings
• root/loris-cron - defines the cache pruning frequency and allowed cache size

Adjustments made

• Own resolver combining SimpleFSResolver serving data from /tmp/static with SimpleHTTPResolver serving data from ARCHE instances and capable of accessing data from a single selected ARCHE instance locally.
• Loris configuration tuned to support WEBP and GIF as source formats and WEBP as an output format.

Debugging

• Apache/WSGI logs are in /var/log/loris/
• After the deployment sources used by the WSGI module are in /usr/local/lib/python3.8/dist-packages/loris.
  • Especially the loris.conf is in /usr/local/lib/python3.8/dist-packages/loris/data/loris.conf
  • After editing the Apache should be restarted with supervisorctl restart apache2
• For experimenting with file formats support:
  • create /tmp/static/ directory owned by the www-data:www-data user/group
  • upload images into it
  • try out with https://loris.acdh.oeaw.ac.at/{imageFileName}/full/full/0/default.jpg
• When experimenting with the code you might need to disable the livenessProbe/readinessProbe/startupProbe of the cluster's workload (so the cluster doesn't restart the workload if something doesn't work for a moment)