api: Add Groups and GroupConfig with Requirements and Labels

* Add Group definitions to associate attribute matchers to particular
Spec specifications to supercede use of machine.json files

cmd/bootcfg/main.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"flag"
+	"io/ioutil"
 	"net/http"
 	"net/url"
 	"os"
@@ -17,6 +18,7 @@ var log = capnslog.NewPackageLogger("github.com/coreos/coreos-baremetal/cmd/boot
 func main() {
 	flags := flag.NewFlagSet("bootcfg", flag.ExitOnError)
 	address := flags.String("address", "127.0.0.1:8080", "HTTP listen address")
+	configPath := flags.String("config", "", "Path to config file")
 	dataPath := flags.String("data-path", "./data", "Path to data directory")
 	imagesPath := flags.String("images-path", "./images", "Path to static assets")
 	// available log levels https://godoc.org/github.com/coreos/pkg/capnslog#LogLevel
@@ -44,13 +46,28 @@ func main() {
 	// logging setup
 	lvl, err := capnslog.ParseLevel(strings.ToUpper(*logLevel))
 	if err != nil {
-		log.Fatalf("Invalid log-level: %s", err.Error())
+		log.Fatalf("Invalid log-level: %v", err.Error())
 	}
 	capnslog.SetGlobalLogLevel(lvl)
 	capnslog.SetFormatter(capnslog.NewPrettyFormatter(os.Stdout, false))
 
+	// storage
+	store := api.NewFileStore(http.Dir(*dataPath))
+
+	// bootstrap a group config
+	if *configPath != "" {
+		data, err := ioutil.ReadFile(*configPath)
+		if err != nil {
+			log.Fatalf("error reading config file: %v", err)
+		}
+		_, err = api.ParseGroupConfig(data)
+		if err != nil {
+			log.Fatalf("error parsing group config: %v", err)
+		}
+	}
+
 	config := &api.Config{
-		Store:     api.NewFileStore(http.Dir(*dataPath)),
+		Store:     store,
 		ImagePath: *imagesPath,
 	}