Issues uploading images from NBU

[dleadbetter]

It appears as though some resources uploaded to IIIF Cloud are not having manifests generated.

[dleadbetter]

@NickLaiacona and @camdendotlol - It looks like the issue with manifests not being generated was still being caused by an R15 error on Heroku. Although we offloaded the image conversion to a worker, ImageMagick itself was still trying to consume more memory than allowed by the Hobby dyno.

To avoid this issue, I've made the following changes on the IIIF Cloud staging environment:

• Set MAGICK_MAP_LIMIT to 256MB and MAGICK_MEMORY_LIMIT to 128MB to limit the memory consumed by ImageMagick and avoid an R15 error
• Increased Redis plan to "Premium 0" to allow for more memory and connections
• Decreased Sidekiq concurrency to "5" to avoid max database connections
• Added heroku-buildpack-graphicsmagick to speed up image conversion

I tested by uploading all of the folders in this Google drive as batches (results currently on staging) and confirmed that the IIIF viewer displayed the same number of images that were uploaded. I would, however, encourage additional testing, as there may be use cases I am not aware of.

One important thing to note:
Since we've offloaded the image conversion and manifest generation to workers, we are not guaranteed that these properties will be present on the resource when the upload request finishes. Depending on the size of the image, the conversion could take several seconds, so we don't want to increase the time for users to upload a batch of records.

Should any issues arise in the future, I've added Papertrail to the app to increase visibility into the logging. The Rails/ActiveJob logs are already quite verbose, so I didn't see the need to manually add any additional logging. Papertrail should also allow searching by time, keyword, etc.

[camdendotlol]

Since we've offloaded the image conversion and manifest generation to workers, we are not guaranteed that these properties will be present on the resource when the upload request finishes. Depending on the size of the image, the conversion could take several seconds, so we don't want to increase the time for users to upload a batch of records.

I think I can address that on NBU's end with the polling prop on the media list, setting it to fetch the latest list of MediaContents every 5 seconds or so.