feat: add kernel metadata fallback

[andyjakubowski]

The goal of this PR is to set kernel metadata on .deepnote files, so you don’t get that Select Kernel dialog every time you open the .deepnote file.

Fallback kernel metadata to use until the .deepnote file format includes kernel information.

Signed-off-by: Andy Jakubowski hello@andyjakubowski.com

Summary by CodeRabbit

• New Features

  • Adds a built-in fallback kernel and language metadata so notebooks lacking kernel info open with sensible defaults.

• Bug Fixes

  • Notebooks missing kernel metadata now open reliably.
  • Notebook metadata is auto-enriched during import/transform to improve compatibility and reduce manual setup.

• Tests

  • New tests cover file-route responses, date formatting, and explicit error handling for missing, permission, and runtime errors.

[linear]

GRN-4810 feat: add kernel metadata fallback

Fallback kernel metadata to use until the .deepnote file format includes kernel information.

So that we don’t show the kernel selection dialog on .deepnote file open.

[coderabbitai]

📝 Walkthrough

Walkthrough

• Added src/kernel-metadata-fallback.ts exporting a constant kernelMetadataFallback containing static kernelspec and language_info.
• Updated src/transform-deepnote-yaml-to-notebook-content.ts to import kernelMetadataFallback and spread it into the returned notebook content metadata so default kernel data is present when missing from the source.
• Added tests in jupyterlab_deepnote/tests/test_handlers.py to validate file-route success and various error mappings; updated cspell.json with new technical words.

Sequence Diagram(s)

sequenceDiagram
    autonumber
    participant C as Caller
    participant T as transformDeepnoteYamlToNotebookContent
    participant Y as Deepnote YAML
    participant F as kernelMetadataFallback

    C->>T: transform(yaml)
    T->>Y: Read metadata from YAML
    alt Kernel info present in YAML
        T->>T: Use YAML kernel metadata
    else No kernel info in YAML
        T->>F: Import and read fallback metadata
        T->>T: Merge fallback into notebook metadata
    end
    T-->>C: Return notebook content with metadata

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Pre-merge checks

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The title succinctly captures the primary change—introducing a fallback for kernel metadata—using clear, conventional commit phrasing without extraneous detail. It directly reflects the core feature added in the pull request.

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[codecov]

Codecov Report

❌ Patch coverage is 95.00000% with 2 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (main@ea98a58). Learn more about missing BASE report.
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/kernel-metadata-fallback.ts	0.00%	1 Missing ⚠️
src/transform-deepnote-yaml-to-notebook-content.ts	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #32   +/-   ##
=======================================
  Coverage        ?   37.29%           
=======================================
  Files           ?       13           
  Lines           ?      244           
  Branches        ?       26           
=======================================
  Hits            ?       91           
  Misses          ?      153           
  Partials        ?        0           

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[coderabbitai]

Actionable comments posted: 1

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Reviewing files that changed from the base of the PR and between ea98a58 and 3db00b1.

📒 Files selected for processing (2)

• src/kernel-metadata-fallback.ts (1 hunks)
• src/transform-deepnote-yaml-to-notebook-content.ts (2 hunks)

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🧬 Code graph analysis (1)

src/transform-deepnote-yaml-to-notebook-content.ts (1)

src/kernel-metadata-fallback.ts (1)

• kernelMetadataFallback (2-20)

🪛 GitHub Actions: CI

src/kernel-metadata-fallback.ts

[error] 3-3: Unknown word (kernelspec)

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[error] 4-4: Unknown word (ipykernel)

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[error] 10-10: Unknown word (ipython)

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[error] 16-16: Unknown word (nbconvert)

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[error] 17-17: Unknown word (pygments)

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[error] 17-17: Unknown word (ipython)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (5)

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🔇 Additional comments (2)

src/kernel-metadata-fallback.ts (1)

3-19: Pipeline spell-check failures are false positives.

Terms like kernelspec, ipykernel, ipython, nbconvert, and pygments are legitimate Jupyter/Python identifiers. Add them to your spell-check dictionary or ignore list.

src/transform-deepnote-yaml-to-notebook-content.ts (1)

5-5: LGTM.

Import and spread correctly provide fallback kernel metadata.

Also applies to: 46-46

[Artmann]

[saltenasl]

@andyjakubowski build and spellchecks failing

[coderabbitai]

Actionable comments posted: 2

📜 Review details

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Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 83182b2 and ae02719.

📒 Files selected for processing (1)

• jupyterlab_deepnote/tests/test_handlers.py (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (1)

jupyterlab_deepnote/tests/test_handlers.py (1)

jupyterlab_deepnote/handlers.py (2)

• RouteHandler (10-59)
• get (15-59)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (3)

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🔇 Additional comments (4)

jupyterlab_deepnote/tests/test_handlers.py (4)

21-24: LGTM!

Correctly validates 400 for missing path parameter.

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45-52: Same mock concern as permission denied test.

Logic correct for 500 on unexpected error. Same verification needed for mock approach.

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27-32: Ignore inconsistency warning; test is correct
contents_manager.get raises tornado.web.HTTPError(404), not FileNotFoundError, so the FileNotFoundError catch is never hit and the generic exception yields a 500—exactly what the test asserts.

Likely an incorrect or invalid review comment.

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35-42: Mocking contents_manager with patch.object(create=True) is correct Instances inherit the class attribute, so the test properly triggers the 403 path. No changes needed.