viewh5

Read-only, keyboard-first HDF5 viewer built with Textual.

Install

uv tool install viewh5

Or install the latest version directly from GitHub:

uv tool install --from git+https://github.com/kabilan108/viewh5 viewh5

Run it with viewh5 open path/to/file.h5.

For a non-interactive summary, use:

viewh5 describe path/to/file.h5

Yazi Previews

viewh5 can be used as both the HDF5 opener and the previewer in Yazi. The preview flow is built around piper.yazi, which runs viewh5 describe and shows the resulting text in Yazi's preview pane.

1. Install viewh5 so the viewh5 command is on your PATH.

uv tool install viewh5

2. Install the piper.yazi plugin:

ya pkg add yazi-rs/plugins:piper

3. Add the opener and preview rules to ~/.config/yazi/yazi.toml:

[opener]
h5 = [
  { run = 'viewh5 open "$@"', block = true, desc = "View HDF5 file" },
]

[open]
prepend_rules = [
  { url = "*.h5", use = [ "h5" ] },
  { url = "*.hdf5", use = [ "h5" ] },
  { url = "*.hdf", use = [ "h5" ] },
]

[plugin]
prepend_previewers = [
  { url = "*.h5", run = 'piper -- viewh5 describe --width "$w" --height "$h" "$1"' },
  { url = "*.hdf5", run = 'piper -- viewh5 describe --width "$w" --height "$h" "$1"' },
  { url = "*.hdf", run = 'piper -- viewh5 describe --width "$w" --height "$h" "$1"' },
]

After restarting Yazi, open on an HDF5 file will launch the full Textual app and hovering an HDF5 file will show the text summary in the preview pane.

Home Manager Setup

If you manage Yazi with Home Manager, the relevant configuration looks like:

programs.yazi = {
  enable = true;
  enableBashIntegration = true;
  plugins = {
    piper = pkgs.yaziPlugins.piper;
  };
  settings = {
    opener = {
      h5 = [
        { run = ''viewh5 open "$@"''; block = true; desc = "View HDF5 file"; }
      ];
    };
    open = {
      prepend_rules = [
        { url = "*.h5"; use = [ "h5" ]; }
        { url = "*.hdf5"; use = [ "h5" ]; }
        { url = "*.hdf"; use = [ "h5" ]; }
      ];
    };
    plugin = {
      prepend_previewers = [
        { url = "*.h5"; run = ''piper -- viewh5 describe --width "$w" --height "$h" "$1"''; }
        { url = "*.hdf5"; run = ''piper -- viewh5 describe --width "$w" --height "$h" "$1"''; }
        { url = "*.hdf"; run = ''piper -- viewh5 describe --width "$w" --height "$h" "$1"''; }
      ];
    };
  };
};

After rebuilding Home Manager, open on an HDF5 file will launch the full Textual app and hovering an HDF5 file will show the text summary in Yazi's preview pane.

Development

uv sync
uv run pytest
uv run ruff check
uv run ty check
uv run viewh5 open data/1520.h5
vhs assets/viewh5-demo.tape

To update snapshots after making changes to the TUI:

uv run pytest tests/test_snapshots.py --snapshot-update

To recreate the demo, make sure the project environment is synced and data/waveforms.h5 is present, then run vhs assets/viewh5-demo.tape.