Allow ONNX imports without external data files

[Copilot]

ONNX model uploads failed when referenced external-data sidecars were absent, although simulation only requires initializer metadata embedded in the model protobuf.

• Model inspection

  • Allow external-data resolution to return no source.
  • Preserve initializer locations, extents, and memory totals.
  • Continue hashing and range-validating supplied sidecars.

• Browser import

  • Import standalone .onnx files without requiring weight data.
  • Continue rejecting unsafe external-data paths.

• Coverage and documentation

  • Add regressions for missing sidecars and path traversal.
  • Document optional browser sidecars and verification behavior.

• Fixes Model parsing should not require the data file #1

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[justinchuby]

@copilot you can test with https://huggingface.co/justinchuby/Muse-Glimmer-30B-ONNX-INT4-CUDA

[Copilot]

@copilot you can test with https://huggingface.co/justinchuby/Muse-Glimmer-30B-ONNX-INT4-CUDA

Hugging Face DNS is blocked in this runner, so I couldn’t download that graph directly. I validated the same external-data encoding with the regression fixture and fixed two related bare-model edge cases in 294d677 (./ sidecar paths and metadata-free architecture classification). Targeted tests and builds pass.

[justinchuby]

@copilot it should just never look at any external data file, because they can be very large

[Copilot]

Pull request overview

This PR updates the ONNX inspection/import pipeline so browser uploads can successfully inspect standalone .onnx protobufs even when referenced external-data sidecars are absent, while still preserving initializer external-data metadata and validating/hash-checking any sidecars that are provided.

Changes:

• Allow resolveExternalData() to return undefined and skip external sidecar hashing/range validation when the sidecar is not supplied.
• Update browser model-package import to treat missing sidecars as optional, while still rejecting unsafe external-data locations.
• Add/adjust tests and documentation to cover missing sidecars, path normalization, and traversal rejection.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
packages/web/src/model-package-import.ts	Makes browser import tolerant of missing external-data sidecars and avoids passing dummy metadata into ONNX architecture normalization.
packages/web/src/model-package-import.test.ts	Adds coverage for missing sidecars, relative-path normalization, and unsafe-path rejection.
packages/onnx-inspector/src/index.ts	Extends the inspector resolver contract to allow “no sidecar supplied” and normalizes external-data locations.
docs/DESIGN.md	Documents that browser imports may omit external-data files while still validating/hash-checking provided sidecars.

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[Copilot]

@copilot it should just never look at any external data file, because they can be very large

Addressed in 9804113: ONNX inspection now never opens, stats, hashes, or range-validates external data sidecar files. It only preserves the external initializer metadata from the protobuf and still rejects unsafe external-data locations.

[justinchuby]

@copilot it should just never look at any external data file, because they can be very large

Addressed in 9804113: ONNX inspection now never opens, stats, hashes, or range-validates external data sidecar files. It only preserves the external initializer metadata from the protobuf and still rejects unsafe external-data locations.

@copilot no need to reject anything if you are not reading it in the first place. External data validation is not this apps concern.

[Copilot]

@copilot it should just never look at any external data file, because they can be very large
...

Addressed in ca42a54: external-data locations are now treated only as ONNX metadata. The inspector preserves them verbatim (or omits them if missing), and browser/CLI imports no longer reject unsafe-looking external-data paths while still never opening sidecars.