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Kumiko

file-derivatives

Declares the derivativeRenderer extension point. ctx.derivatives.variant(fileRefId, spec, name) derives a variant of a tracked FileRef the first time it’s requested and reuses the stored result afterwards (derive-on-first-use, keyed by a hash of the spec). Mount at least one derivatives-* renderer feature alongside this one — without a registered renderer for the FileRef’s MIME type, every variant(...) call throws. Also declares the derivativePublicPredicate extension point (r.useExtension(EXT_DERIVATIVE_PUBLIC_PREDICATE, '<entityType>', { isPublic })) and, when createFileDerivativesFeature({resolveApexTenant}) is passed a host-resolver, mounts an anonymous GET {basePath}/:fileRefId/:variant route that serves any variant name the FileRef’s field declared in its variants for a FileRef whose entityType has a registered predicate returning true — default-deny (404) otherwise, same as an unknown FileRef or an undeclared variant name. The route’s only rate-limit (per: "ip") trusts the first x-forwarded-for hop — deployers must ensure their ingress overwrites rather than appends to that header, or the throttle is bypassable by rotating it.

How it fits

Section titled “How it fits”

What this feature needs to run (Requires).

flowchart TB
  n_file_derivatives["file-derivatives"]
  subgraph how_reqs["Requires"]
    n_file_foundation["file-foundation"]
    n_files["files"]
  end
  n_file_foundation --> n_file_derivatives
  n_files --> n_file_derivatives

Dependencies

Section titled “Dependencies”