GBIF runs a Thumbor server to perform caching, cropping, resizing and filtering of images.
For general instructions, see the Thumbor documentation. This file documents how our server is installed, configured and used.
See the Thumbor documentation. With this image, https://apps.rhs.org.uk/plantselectorimages/detail/WSY0036490_3534.jpg, we can simply cache it:
or we can resize and crop it to 300×80px, and flip it horizontally, with the URL https://api.gbif.org/v1/image/rDlLGuaR5hxtaygg_AAYzw-amcg=/-300x80/https://apps.rhs.org.uk/plantselectorimages/detail/WSY0036490_3534.jpg
Using fit-in/ we can resize it without cropping, and maintain the aspect ratio: https://api.gbif.org/v1/image/8JRfI6JDTXNflBLc3E91Ok9lEHk=/fit-in/-300x80/https://apps.rhs.org.uk/plantselectorimages/detail/WSY0036490_3534.jpg
Adding the filter /filters:quality(5) sets the JPEG quality:
/https://apps.rhs.org.uk/plantselectorimages/detail/WSY0036490_3534.jpg)
To allow secure, public use of occurrence images, these may be accessed without the security key.
An occurrence with gbifId 2005380410 and a media identifier https://inaturalist-open-data.s3.amazonaws.com/photos/31610070/original.jpg may be accessed with a URL like
https://api.gbif.org/v1/image/cache/occurrence/[gbifId]/media/[md5sum(identifier]
https://api.gbif.org/v1/image/cache/occurrence/2005380410/media/568639b65b65ddb9090d3d6ef1abce14
URLs must include a signature, to prevent others from using the service. Thumbor's documentation lists libraries for generating keys. We use [Not yet decided] Node library to generate these keys for the portal. The secret key needed is in the usual place.
For testing or debugging, you can generate keys on thumbor-vh.gbif.org:
$ imageurl 400x-600/https://apps.rhs.org.uk/plantselectorimages/detail/WSY0036490_3534.jpg
https://api.gbif.org/v1/image/PHSKQQvKlQX_hIuBAIbwFNJB1bQ=/400x-600/https%3A//apps.rhs.org.uk/plantselectorimages/detail/WSY0036490_3534.jpg
or using Thumbor's utility, /usr/local/bin/thumbor-url.
The service is running in "unsafe" mode (not requiring a key). This will be disabled once the old portal is replaced.
The server is set to cache source images indefinitely, and produce images with a JPEG quality of 80 by default. Feature detection is not installed.
Twenty processes run, ten on two servers, which Varnish accesses with a round-robin director.
The processes are monitored by Nagios and 2.
The servers has DNS aliases: thumbor1.gbif.org and thumbor2.gbif.org, and similarly for UAT and Dev.
Installation is with Ansible, using the GBIF scripts, which are based on ansible-thumbor-centos. The thumbor_hbase plugin is used, including a the customization for occurrence images.
The installed version is:
$ thumbor --version
Thumbor v7.4.7 (26-Jan-2023)