[Bug] Unable to load IIIF Georef AnnotationPage for sanborn00813_033

[danvk]

Describe the problem

When I visit https://oldinsurancemaps.net/map/sanborn00813_033 and click the link to https://oldinsurancemaps.net/iiif/mosaic/sanborn00813_033/main-content/?trim=true, it consistently waits a minute and responds with

504 Gateway Time-out
nginx/1.18.0 (Ubuntu)

Expected behavior

It should produce the IIIF JSON file.

To Reproduce

See above.

Environment info:

n/a

[mradamcox]

Looks like this is a good old-fashioned timeout. The process that generates the georeference annotation takes a second or two per layer, and this particular volume has 380 layers (SF maps needed to be extra split because the road widths were not drawn to scale) so it just takes too long.

I think the best fix will be to cache the IIIF georef annotation on the Layer db objects themselves instead of generating it on the fly.