blob: d22f901f92fb19a2cb630793e8e52f89e14657a6 [file] [log] [blame]
# Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Helper functions for building graphs with dot."""
import subprocess
class Subgraph(object):
"""A subgraph in dot. Contains nodes, arcs, and other subgraphs."""
_valid_ranks = set(['source', 'sink', 'same', 'min', 'max', None])
def __init__(self, rank=None):
self._nodes = []
self._subgraphs = []
self._arcs = set()
def SetRank(self, rank):
"""Sets the rank for the nodes in the graph.
Can be one of 'source', 'sink', 'same', 'min', 'max' or None. See dot
documentation at for exact
assert(rank in self._valid_ranks)
self._rank = rank
def AddNode(self, id, name=None, color=None, href=None):
"""Adds a node to the subgraph."""
tags = {}
if name:
tags['label'] = name
if color:
tags['color'] = color
tags['fontcolor'] = color
if href:
tags['href'] = href
self._nodes.append({'id': id, 'tags': tags})
def AddSubgraph(self, subgraph):
"""Adds a subgraph to the subgraph."""
def AddNewSubgraph(self, rank=None):
"""Adds a new subgraph to the subgraph. The new subgraph is returned."""
subgraph = Subgraph(rank)
return subgraph
def AddArc(self, node_from, node_to):
"""Adds an arc between two nodes."""
self._arcs.add((node_from, node_to))
def _GenNodes(self):
"""Generates the code for all the nodes."""
lines = []
for node in self._nodes:
tags = ['%s="%s"' % (k, v) for (k, v) in node['tags'].iteritems()]
lines.append('"%s" [%s];' % (node['id'], ', '.join(tags)))
return lines
def _GenSubgraphs(self):
"""Generates the code for all the subgraphs contained in this subgraph."""
lines = []
for subgraph in self._subgraphs:
lines += subgraph.Gen();
return lines
def _GenArcs(self):
"""Generates the code for all the arcs."""
lines = []
for node_from, node_to in self._arcs:
lines.append('"%s" -> "%s";' % (node_from, node_to))
return lines
def _GenInner(self):
"""Generates the code for the inner contents of the subgraph."""
lines = []
if self._rank:
lines.append('rank=%s;' % self._rank)
lines += self._GenSubgraphs()
lines += self._GenNodes()
lines += self._GenArcs()
return lines
def Gen(self):
"""Generates the code for the subgraph."""
return ['subgraph {'] + self._GenInner() + ['}']
class Graph(Subgraph):
"""A top-level graph in dot. It's basically a subgraph with a name."""
def __init__(self, name):
self._name = name
def Gen(self):
"""Generates the code for the graph."""
return ['digraph "%s" {' % self._name,
'graph [name="%s"];' % self._name] + self._GenInner() + ['}']
def GenerateImage(lines, filename, format='svg', save_dot_filename=None):
"""Generates the image by calling dot on the input lines."""
data = '\n'.join(lines)
proc = subprocess.Popen(['dot', '-T' + format, '-o' + filename],
if save_dot_filename:
file = open(save_dot_filename, 'w')