Custom notebook metadata not stored

[IanHawke]

When converting an old notebook using jupytext from the command line to an alternate format (tried md and py), any custom metadata added to the entire notebook (not to an individual cell) is not stored in the resulting text file.

I was running jupytext on the notebooks at https://github.com/IanHawke/maths-with-python to test. There's custom notebook level metadata (under the "nbconvert" group, called "title") to use in a hacky ipynb->pdf book pipeline. The pipeline probably won't be useful, but notebook-level metadata might be useful for other purposes.

[mwouts]

Hello Ian, indeed by default a filter is applied to the metadata. The use of these filters is documented here in the context of Jupyter.

But I see it's not documented in the context of the command line, I'll try to fix this at some point. Anyway, I think what you are looking for is --update-metadata '{"jupytext": {"notebook_metadata_filter":"all"}}'. See for instance:

srv002983:~$ jupytext --to md --update-metadata '{"jupytext": {"notebook_metadata_filter":"all"}}' 00-first-steps.ipynb  -o - | head -n 26

---
jupyter:
  jupytext:
    notebook_metadata_filter: all
    text_representation:
      extension: .md
      format_name: markdown
      format_version: '1.1'
      jupytext_version: 1.2.3
  kernelspec:
    display_name: Python 3
    language: python
    name: python3
  language_info:
    codemirror_mode:
      name: ipython
      version: 3
    file_extension: .py
    mimetype: text/x-python
    name: python
    nbconvert_exporter: python
    pygments_lexer: ipython3
    version: 3.4.4
  nbconvert:
    title: First Steps
---

[IanHawke]

Brilliant, thanks.