Sorl not working with Apache

Symptoms

- works well with native development server

- as soon as we switch to apache --> thumbnails stop getting generated

Issues:

- no log messages at usual places, /var/log/apache2/error.log

Findings:

- read sorl code + documentation

Documentation:

https://sorl-thumbnail.readthedocs.io/en/latest/examples.html#model-examples

http://sorl-thumbnail.readthedocs.io/en/latest/logging.html

Sorl code:

https://github.com/jazzband/sorl-thumbnail/search?utf8=%E2%9C%93&q=get_thumbnail&type=

-->

- Sorl default logger is email:

http://sorl-thumbnail.readthedocs.io/en/latest/logging.html

- converted the default email logger to file logger -->

- reading the logs found out that MEDIA_ROOT was not correctly set.

usually is os.path.join(DJANGO_ROOT,'media')

(was trying to use Apache default, DocumentRoot /var/www/ )

- and hence was running into permission issues.