widgetron 0.2.6

<img src="https://user-images.githubusercontent.com/48299585/213842033-c0c19779-84b9-4a07-83a0-9b75ef4b3971.JPG" alt="drawing" width="500"/>

This command line utility builds a standalone executable installer for a
single ipython notebook. It is intended for applications built with
ipywidgets.

## Quickstart
```
conda install boa constructor nodejs jake -c conda-forge
pip install widgetron
widgetron -h
```

### How it Works

1. Builds and packages a minimal electron interface to navigate to
   `localhost:8866` and boot up the `jupyter lab` server.
2. Copies a notebook or directory of notebooks (specified by `-nb`) into a
   template python package.
3. Copies the entire contents of the built electron application into the
   template python package.
4. Makes a conda-package out of the python package template to hold the
   notebook and packaged electron app.
5. Builds an installer using conda/constructor.

### Development Guide
Before you run `widgetron`
1. Conda dependencies are specified using one of the following paradigms. (pip dependencies are ignored)

   - `dependencies` and `channels`. 2 lists of strings identifying which packages
      to search for and which channels are searched.
      e.g. `widgetron . -nb my_notebook.ipynb --dependencies numpy matplotlib --channels conda-forge`
      `jupyterlab`, `conda`, and `menuinst` (if Windows) are included by default.
   - `environment`. Pre-built conda environment which must contain `jupyterlab`
      `conda` and `menuinst` (if Windows).
   - `explicit_lock`. Lockfile representing the exact package urls to be included
      in the environment. This env will be built within the widgetron work directory
      and the installer will be built from that env. This option allows the
      creatioin of a Software Bill of Materials (SBOM) for the conda packages.

2. Create a `pyproject.toml` or `setup.cfg` and follow the examples to see
   how these should be formatted.

3. If you have additional source code to include there are two options for how to do so

   - (Recommended) create a conda package (using `conda-build`) and add it to the `-deps` argument.
   - (Easy, and dangerous) Include the raw source files

      - If your `--notebook` argument is a single notebook, then point the `-src` parameter to the root of your python module.
      - If your `--notebook` argument is a directory, then your source code must be placed inside this directory and be relatively importable.
      - __Warning__: this includes __EVERYTHING__ so delete your `__pycache__`s and `.env`s etc.

4. Provide any metadata you want (see `widgetron -h` or `src/widgetron/args.yml` for options)

5. run `widgetron` in the same directory as the `toml` or `cfg` file

   - This will immediately render all of the templates so you can inspect them in a new `widgetron_temp_files` directory.
   - I recommend looking at `constructor/construct.yaml` and `server/widgetron_app/notebooks` especially.
   - If something is obviously wrong, stop widgetron and fix it.
   - Otherwise, wait for the installer to be created, then run it and make sure everything works.
   - If you get some import errors, then there's likely something missing from the environment.yml/lock
   - There's also a debug notebook that you can run to get some useful info about how jupyterlab is running.

### Example

After the `widgetron` command the installer is placed in the current working directory

![image](https://user-images.githubusercontent.com/48299585/211173752-212a2d77-9238-412f-81f8-0f942f276749.png)

Running the installer

![image](https://user-images.githubusercontent.com/48299585/211173763-fc7b54ad-c8cf-4386-94d8-cfc90cdb77d8.png)

Startmenu Shortcut

![image](https://user-images.githubusercontent.com/48299585/211173745-9142808c-6303-4925-b1f2-d7db21430df1.png)

Window

![image](https://user-images.githubusercontent.com/48299585/211173814-af05502c-2c41-4bd1-ad09-324a9eccef78.png)

Profit