class StateMachine::Graph

Provides a set of higher-order features on top of the raw GraphViz graphs

Attributes

file_format[R]

The image format to generate the graph in

file_path[R]

The graph's full filename

font[R]

The name of the font to draw state names in

Public Class Methods

new(name, options = {}) click to toggle source

Creates a new graph with the given name.

Configuration options:

  • :path - The path to write the graph file to. Default is the current directory (“.”).

  • :format - The image format to generate the graph in. Default is “png'.

  • :font - The name of the font to draw state names in. Default is “Arial”.

  • :orientation - The direction of the graph (“portrait” or “landscape”). Default is “portrait”.

Calls superclass method
# File lib/state_machine/graph.rb, line 37
def initialize(name, options = {})
  options = {:path => '.', :format => 'png', :font => 'Arial', :orientation => 'portrait'}.merge(options)
  assert_valid_keys(options, :path, :format, :font, :orientation)
  
  @font = options[:font]
  @file_path = File.join(options[:path], "#{name}.#{options[:format]}")
  @file_format = options[:format]
  
  super('G', :rankdir => options[:orientation] == 'landscape' ? 'LR' : 'TB')
end

Public Instance Methods

add_edges(*args) click to toggle source

Adds a new edge to the graph. The font for the edge will be automatically set based on the graph configuration. The generated edge will be returned.

For example,

graph = StateMachine::Graph.new('test')
graph.add_edges('parked', 'idling', :label => 'ignite')
Calls superclass method
# File lib/state_machine/graph.rb, line 75
def add_edges(*args)
  edge = v0_api? ? add_edge(*args) : super
  edge.fontname = @font
  edge
end
add_nodes(*args) click to toggle source

Adds a new node to the graph. The font for the node will be automatically set based on the graph configuration. The generated node will be returned.

For example,

graph = StateMachine::Graph.new('test')
graph.add_nodes('parked', :label => 'Parked', :width => '1', :height => '1', :shape => 'ellipse')
Calls superclass method
# File lib/state_machine/graph.rb, line 62
def add_nodes(*args)
  node = v0_api? ? add_node(*args) : super
  node.fontname = @font
  node
end
output() click to toggle source

Generates the actual image file based on the nodes / edges added to the graph. The path to the file is based on the configuration options for this graph.

Calls superclass method
# File lib/state_machine/graph.rb, line 51
def output
  super(@file_format => @file_path)
end

Private Instance Methods

v0_api?() click to toggle source

Determines whether the old v0 api is in use

# File lib/state_machine/graph.rb, line 83
def v0_api?
  version[0] == '0' || version[0] == '1' && version[1] == '0' && version[2] <= '2'
end
version() click to toggle source

The ruby-graphviz version data

# File lib/state_machine/graph.rb, line 88
def version
  Constants::RGV_VERSION.split('.')
end