Initial public commit of mgmt

This is a prototype that i'm attempting to "release early". Expect a lot
of changes! It is intended to be a config management tool that will:

* be event based
* execute actions in parallel
* function as a distributed system

There are a bunch more design ideas going into this, please stay tuned!

config.go

@@ -0,0 +1,126 @@
+// Mgmt
+// Copyright (C) 2013-2015+ 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 main
+
+import (
+	"errors"
+	"gopkg.in/yaml.v2"
+	"io/ioutil"
+	"log"
+)
+
+type noopTypeConfig struct {
+	Name string `yaml:"name"`
+}
+
+type fileTypeConfig struct {
+	Name    string `yaml:"name"`
+	Path    string `yaml:"path"`
+	Content string `yaml:"content"`
+	State   string `yaml:"state"`
+}
+
+type serviceTypeConfig struct {
+	Name    string `yaml:"name"`
+	State   string `yaml:"state"`
+	Startup string `yaml:"startup"`
+}
+
+type vertexConfig struct {
+	Type string `yaml:"type"`
+	Name string `yaml:"name"`
+}
+
+type edgeConfig struct {
+	Name string       `yaml:"name"`
+	From vertexConfig `yaml:"from"`
+	To   vertexConfig `yaml:"to"`
+}
+
+type graphConfig struct {
+	Graph string `yaml:"graph"`
+	Types struct {
+		Noop    []noopTypeConfig    `yaml:"noop"`
+		File    []fileTypeConfig    `yaml:"file"`
+		Service []serviceTypeConfig `yaml:"service"`
+	} `yaml:"types"`
+	Edges   []edgeConfig `yaml:"edges"`
+	Comment string       `yaml:"comment"`
+}
+
+func (c *graphConfig) Parse(data []byte) error {
+	if err := yaml.Unmarshal(data, c); err != nil {
+		return err
+	}
+	if c.Graph == "" {
+		return errors.New("Graph config: invalid `graph`")
+	}
+	return nil
+}
+
+func GraphFromConfig(filename string) *Graph {
+
+	var NoopMap map[string]*Vertex = make(map[string]*Vertex)
+	var FileMap map[string]*Vertex = make(map[string]*Vertex)
+	var ServiceMap map[string]*Vertex = make(map[string]*Vertex)
+
+	var lookup map[string]map[string]*Vertex = make(map[string]map[string]*Vertex)
+	lookup["noop"] = NoopMap
+	lookup["file"] = FileMap
+	lookup["service"] = ServiceMap
+
+	data, err := ioutil.ReadFile(filename)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	var config graphConfig
+	if err := config.Parse(data); err != nil {
+		log.Fatal(err)
+	}
+	//fmt.Printf("%+v\n", config)	// debug
+
+	g := NewGraph(config.Graph)
+
+	for _, t := range config.Types.Noop {
+		NoopMap[t.Name] = NewVertex(t.Name, "noop")
+		// FIXME: duplicate of name stored twice... where should it go?
+		NoopMap[t.Name].Associate(NewNoopType(t.Name))
+		g.AddVertex(NoopMap[t.Name]) // call standalone in case not part of an edge
+	}
+
+	for _, t := range config.Types.File {
+		FileMap[t.Name] = NewVertex(t.Name, "file")
+		// FIXME: duplicate of name stored twice... where should it go?
+		FileMap[t.Name].Associate(NewFileType(t.Name, t.Path, t.Content, t.State))
+		g.AddVertex(FileMap[t.Name]) // call standalone in case not part of an edge
+	}
+
+	for _, t := range config.Types.Service {
+		ServiceMap[t.Name] = NewVertex(t.Name, "service")
+		// FIXME: duplicate of name stored twice... where should it go?
+		ServiceMap[t.Name].Associate(NewServiceType(t.Name, t.State, t.Startup))
+		g.AddVertex(ServiceMap[t.Name]) // call standalone in case not part of an edge
+	}
+
+	for _, e := range config.Edges {
+		g.AddEdge(lookup[e.From.Type][e.From.Name], lookup[e.To.Type][e.To.Name], NewEdge(e.Name))
+	}
+
+	return g
+}