controller.go

package nucleus

import (
	"code.fbi.h-da.de/cocsn/gosdn/database"
	"github.com/BurntSushi/toml"
	"github.com/google/uuid"
	log "github.com/sirupsen/logrus"
	"os"
)

type controllerConfig struct {
	CliSocket        string
	DatabaseSocket   string
	DatabaseUser     string
	DatabasePassword string
	DatabaseCrypto   bool
	ConfigPath       string
}

// Core is the representation of the controllers core
type Core struct {
	southboundInterfaces   map[string]SouthboundInterface
	prinipalNetworkDomains map[uuid.UUID]PrincipalNetworkDomain
	database               database.Database
	config                 controllerConfig
	IsRunning              chan bool
}

//Init does start-up housekeeping like reading controller config files
func (c *Core) Init(socket, configFileController, configFileClient string, IsRunningChannel chan bool) {
	if err := c.readControllerConfig(configFileController); err != nil {
		log.Fatal(err)
	}

	if socket != "localhost:55055" {
		c.config.CliSocket = socket
	}

	c.AttachDatabase()

	c.IsRunning = IsRunningChannel
}

// AttachDatabase connects to the database and passes the connectio to the controller core
func (c *Core) AttachDatabase() {
	c.database = database.NewDatabaseClient(c.config.DatabaseSocket, c.config.DatabaseUser, c.config.DatabasePassword, c.config.DatabaseCrypto)
}

// Shutdown waits for the shutdown signal and gracefully shuts down once it arrived
func (c *Core) Shutdown() {
	<-c.IsRunning
	log.Info("Received shutdown signal. Shutting down")

	f, err := os.Create(c.config.ConfigPath)
	if err != nil {
		log.Fatal(err)
	}
	enc := toml.NewEncoder(f)
	if err := enc.Encode(c.config); err != nil {
		log.Fatal(err)
	}
	log.Info("Shutdown complete")
	os.Exit(0)
}

func (c *Core) readControllerConfig(configFileController string) error {
	if configFileController == "" {
		configFileController = "configs/gosdn.toml"
	}
	if _, err := os.Stat(configFileController); err != nil {
		return err
	}

	c.config = controllerConfig{}
	if _, err := toml.DecodeFile(configFileController, &c.config); err != nil {
		return err
	}

	if c.config.ConfigPath == "" {
		c.config.ConfigPath = configFileController
	}
	return nil
}