jupyter_anywidget_graphviz

Jupyter anywidget for rendering diagrams from .dot language to SVG using Graphviz Wasm (hpcc-systems/hpcc-js-wasm).

Install as:

pip install jupyter_anywidget_graphviz

Usage

This runs in a browser based Jupyter environment and uses the browser machinery to run the wasm application.

# Import package
from jupyter_anywidget_graphviz import graphviz_headless, graphviz_panel, graphviz_inline

# Create a headless widget
# - works in: Jupyter Lab, Jupyter Notebook, VS Code
g = graphviz_headless()

# Inline mode
# Preview output as cell output from initialising cell
# - works in: Jupyter Lab, Jupyter Notebook, VS Code
# g = graphviz_inline()

# Create a widget panel with a handle
# - uses jupyter sidecar (Jupyter Lab only)
#g = graphviz_panel()

# Load magic
%load_ext jupyter_anywidget_graphviz

We can now write dot code in a magicked code cell (%%graphviz_magic WIDGET_HANDLE):

%%graphviz_magic -w g
  strict graph {
    a -- b
    a -- b
    b -- a [color=blue]
  }

The -w / --widget-name setting can be used to set the widget within the magic and it does not need to be passed again.

The widget can also be set via line magic: %setwidget g

The output is previewed in the UI panel, if rendered.

Retrieve the SVG diagram as WIDGET_HANDLE.svg.

We can display the diagram in the notebook e.g. as:

from IPython.display import SVG

SVG(g.svg)

In its base form, the way the Jupyter event loop runs means we canlt directly generate an output from the magic cell. However, setting the -e/--embed flag, or setting a timeout -t/--timeout SECONDS (default 5s), we can force a blocking action on the cell that waits for the asynchronous graphviz object to return the gernerated SVG, and then render it.

The .blocking_reply() method on the object will also block until the response status is set to completed.

Alternative solutions

viz.js [repo] also seems to offer in browser graphviz rendering. KrunkZhou/jupyterlab-viz-krunk is a JupyterLab extension (untested) that seems to support backticked ```graphviz blocks in markdown cells.

Here'a an alternative anywidget using the same graphviz wasm package from @basnijholt: https://github.com/pipefunc/graphviz-anywidget

Other (predominantly, ouseful) sideloading wasm anywidgets

See the GitHup topc tag: jupyter-wasm-anywidget-extension