[BUG] File access is not ensured before attempting to use them in IIIF/OpenSeadragon

[adam-vessey]

What steps does it take to reproduce the issue?

• When does this issue occur?

This was encountered when setting a "file"-level embargo using the dgi's fork of the embargoes module; however, any other mechanism to constrain access to particular file entities would similarly cause it to happen.

• Which page does it occur on?

Viewing images/paged content which make use of IIIF manifests where the current user does not have access to to the file entities referenced from the media selected for use in the displays.

• What happens?

Broken viewers are shown, with 403 errors emitted to browser consoles (and presumably to Drupal's watchdog logs).

• To whom does it occur (anonymous visitor, editor, administrator)?

Those without access to the referenced files.

• What did you expect to happen?

Viewers would not be visible or not attempt to render elements for entities to which the user does not have access.

Which version of Islandora are you using?

2.4.0

Any related open or closed issues to this bug report?

Unknown; though, here's a number of PRs addressing things:

• Add file access check to IIIF manifest generation. islandora#884
  • addressing the inclusion of access-controlled file entities in IIIF manifests generated by islandora_iiif
• Fix/file access openseadragon#42
  • addressing the inclusion of access-controlled file entities in the one-off media formatter field (and some caching metadata on the block)
• Add interface and use trait to make the config service a cacheable dependency openseadragon#41
  • an optimization to better deal with caching, associated with Fix/file access openseadragon#42

Screenshots:

[seth-shaw-asu]

Anything else, @adam-vessey?

[adam-vessey]

Nah, that was it... except... I guess, releases of the two things, islandora and openseadragon? Drafted... sane (assuming they're visible)?:

• https://github.com/Islandora/islandora/releases/tag/untagged-1e1e9e3fd185b3012538 https://github.com/Islandora/islandora/releases/tag/2.4.3
• https://github.com/Islandora/openseadragon/releases/tag/untagged-7d244167655e8480fbe0 https://github.com/Islandora/openseadragon/releases/tag/2.0.2