Files
mgmt/pgraph/graphviz.go
James Shubin 9b9ff2622d resources: Make resource kind and baseuid fields public
This is required if we're going to have out of package resources. In
particular for third party packages, and also for if we decide to split
out each resource into a separate sub package.
2017-04-11 01:52:21 -04:00

119 lines
3.3 KiB
Go

// Mgmt
// Copyright (C) 2013-2017+ James Shubin and the project contributors
// Written by James Shubin <james@shubin.ca> and the project contributors
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package pgraph // TODO: this should be a subpackage
import (
"fmt"
"io/ioutil"
"os"
"os/exec"
"strconv"
"syscall"
)
// Graphviz outputs the graph in graphviz format.
// https://en.wikipedia.org/wiki/DOT_%28graph_description_language%29
func (g *Graph) Graphviz() (out string) {
//digraph g {
// label="hello world";
// node [shape=box];
// A [label="A"];
// B [label="B"];
// C [label="C"];
// D [label="D"];
// E [label="E"];
// A -> B [label=f];
// B -> C [label=g];
// D -> E [label=h];
//}
out += fmt.Sprintf("digraph %s {\n", g.GetName())
out += fmt.Sprintf("\tlabel=\"%s\";\n", g.GetName())
//out += "\tnode [shape=box];\n"
str := ""
for i := range g.Adjacency { // reverse paths
out += fmt.Sprintf("\t\"%s\" [label=\"%s[%s]\"];\n", i.GetName(), i.GetKind(), i.GetName())
for j := range g.Adjacency[i] {
k := g.Adjacency[i][j]
// use str for clearer output ordering
if k.Notify {
str += fmt.Sprintf("\t\"%s\" -> \"%s\" [label=\"%s\",style=bold];\n", i.GetName(), j.GetName(), k.Name)
} else {
str += fmt.Sprintf("\t\"%s\" -> \"%s\" [label=\"%s\"];\n", i.GetName(), j.GetName(), k.Name)
}
}
}
out += str
out += "}\n"
return
}
// ExecGraphviz writes out the graphviz data and runs the correct graphviz
// filter command.
func (g *Graph) ExecGraphviz(program, filename, hostname string) error {
switch program {
case "dot", "neato", "twopi", "circo", "fdp":
default:
return fmt.Errorf("invalid graphviz program selected")
}
if filename == "" {
return fmt.Errorf("no filename given")
}
if hostname != "" {
filename = fmt.Sprintf("%s@%s", filename, hostname)
}
// run as a normal user if possible when run with sudo
uid, err1 := strconv.Atoi(os.Getenv("SUDO_UID"))
gid, err2 := strconv.Atoi(os.Getenv("SUDO_GID"))
err := ioutil.WriteFile(filename, []byte(g.Graphviz()), 0644)
if err != nil {
return fmt.Errorf("error writing to filename")
}
if err1 == nil && err2 == nil {
if err := os.Chown(filename, uid, gid); err != nil {
return fmt.Errorf("error changing file owner")
}
}
path, err := exec.LookPath(program)
if err != nil {
return fmt.Errorf("the Graphviz program is missing")
}
out := fmt.Sprintf("%s.png", filename)
cmd := exec.Command(path, "-Tpng", fmt.Sprintf("-o%s", out), filename)
if err1 == nil && err2 == nil {
cmd.SysProcAttr = &syscall.SysProcAttr{}
cmd.SysProcAttr.Credential = &syscall.Credential{
Uid: uint32(uid),
Gid: uint32(gid),
}
}
_, err = cmd.Output()
if err != nil {
return fmt.Errorf("error writing to image")
}
return nil
}