# SPDX-License-Identifier: BSD-3-Clause
# Copyright (c) 2023 Scipp contributors (https://github.com/scipp)
from html import escape
from itertools import chain
from .node_class import Node
from .view import View
def _make_graphviz_digraph(*args, **kwargs):
try:
from graphviz import Digraph
except ImportError:
raise RuntimeError(
"Failed to import `graphviz`. "
"Use `pip install graphviz` (requires installed `graphviz` executable) or "
"`conda install -c conda-forge python-graphviz`."
) from None
return Digraph(*args, **kwargs)
def _walk_graph(start, nodes, edges, views, labels):
label = (
escape(str(start.func)) + '\nid = ' + start.id
if start.name is None
else escape(start.name)
)
nodes[start.id] = label
for child in start.children:
if start.id not in edges:
edges[start.id] = {child.id}
else:
edges[start.id].add(child.id)
_walk_graph(
start=child,
nodes=nodes,
edges=edges,
views=views,
labels=labels,
)
for arg_name, parent in chain(
((f'arg_{i}', p) for i, p in enumerate(start.parents)), start.kwparents.items()
):
key = parent.id
if key not in labels:
labels[key] = arg_name
if key not in nodes:
if key not in edges:
edges[key] = {start.id}
else:
edges[key].add(start.id)
_walk_graph(
start=parent,
nodes=nodes,
edges=edges,
views=views,
labels=labels,
)
for view in start.views:
need_walk = False
if view.id not in views:
need_walk = True
views[view.id] = view.__class__.__name__
if start.id not in edges:
edges[start.id] = {view.id}
else:
edges[start.id].add(view.id)
if need_walk:
for node in view.graph_nodes.values():
_walk_graph(
start=node,
nodes=nodes,
edges=edges,
views=views,
labels=labels,
)
def _make_graph(dot, nodes, edges, labels, views):
for key, lab in nodes.items():
dot.node(key, label=lab)
for key, lab in views.items():
dot.node(key, label=lab, shape='ellipse', style='filled', color='lightgrey')
for parent, children in edges.items():
for child in children:
dot.edge(
parent,
child,
label=labels.get(parent, '') if child not in views else '',
)
return dot
[docs]
def show_graph(entry: Node | View, **kwargs):
"""
Display the connected nodes and views as a graph.
Parameters
----------
entry:
An entry point in the graph (node or view). This can be any node/view in the
graph. The graph will be searched from end to end to construct the diagram.
**kwargs:
Additional keyword arguments are forwarded to ``graphviz.Digraph``.
Returns
-------
:
A visual representation of the graph generated with Graphviz.
"""
dot = _make_graphviz_digraph(strict=True, graph_attr=kwargs)
dot.attr('node', shape='box', height='0.1')
nodes = {}
edges = {}
views = {}
labels = {}
# If input is a View, get the underlying node
if hasattr(entry, 'graph_nodes'):
entry = next(iter(entry.graph_nodes.values()))
_walk_graph(
start=entry,
nodes=nodes,
edges=edges,
views=views,
labels=labels,
)
return _make_graph(dot=dot, nodes=nodes, edges=edges, labels=labels, views=views)
