github.com/bendemaree/terraform@v0.5.4-0.20150613200311-f50d97d6eee6/digraph/graphviz.go (about)

     1  package digraph
     2  
     3  import (
     4  	"fmt"
     5  	"io"
     6  )
     7  
     8  // WriteDot is used to emit a GraphViz compatible definition
     9  // for a directed graph. It can be used to dump a .dot file.
    10  func WriteDot(w io.Writer, nodes []Node) error {
    11  	w.Write([]byte("digraph {\n"))
    12  	defer w.Write([]byte("}\n"))
    13  
    14  	for _, n := range nodes {
    15  		nodeLine := fmt.Sprintf("\t\"%s\";\n", n)
    16  
    17  		w.Write([]byte(nodeLine))
    18  
    19  		for _, edge := range n.Edges() {
    20  			target := edge.Tail()
    21  			line := fmt.Sprintf("\t\"%s\" -> \"%s\" [label=\"%s\"];\n",
    22  				n, target, edge)
    23  			w.Write([]byte(line))
    24  		}
    25  	}
    26  
    27  	return nil
    28  }