parseTemplateCreateConf.go

package templateCreate

import (
	"flag"
	"os"
	"strings"

	"github.com/sirupsen/logrus"
	"gopkg.in/yaml.v3"
)

var configPath_default = "templateCreate/templateCreate.clab_vars.yaml" // config path if no other path is given via -config flag
var tcConf *TemplateCreateConfig                                        // pointer to parsed config
var peerGenMode string

// ipPrefix: ipBase without number after last ".".
// e.g. ipBase = "172.100.20.0" -> ipPrefix = "172.100.20.".
var ipPrefix string
var curSubnetNr int

func ParseTemplateCreateConfig() {
	// TODO: flag validation
	configPath := flag.String("config", "", "path to the config file")
	logLevel := flag.String("log", "", "logrus log level (debug, info, warn, error, fatal, panic)")
	ekmsNum := flag.Int("ekms", 0, "number of EKMS to generate")
	mode := flag.String("mode", "", "peer generation mode")
	flag.IntVar(ekmsNum, "kms", 0, "number of KMS to generate")       // -kms: alias for -ekms
	flag.StringVar(configPath, "conf", "", "path to the config file") // -conf: alias for -config

	flag.Parse()

	setLogLevel(logLevel)
	setConfigPath(configPath)

	// unmarshal config
	config := &TemplateCreateConfig{}
	file, err := os.ReadFile(*configPath)
	if err != nil {
		logrus.Fatal(err)
	}
	if err := yaml.Unmarshal(file, config); err != nil {
		logrus.Fatal(err)
	}
	// set TemplateCreateConfig variable
	tcConf = config
	//logrus.Info(*tcConf) // print entire parsed config

	setEkmsNumber(ekmsNum)
	setPeerGenMode(mode)
	setConfVals()
}

func setConfVals() {
	// IP without part after last dot, but including last dot
	// to add the subnet numbers to for individual IPs
	// e.g. ipBase: 172.100.20.4 -> ipPrefix: 172.100.20.
	ipPrefix = tcConf.General.IpBase[:strings.LastIndex(tcConf.General.IpBase, ".")+1]
	// the next free subnet number in the network
	// control nodes start from .1
	// e.g. 5 control nodes, xxx.xxx.xx.1 - xxx.xxx.xx.6 -> curSubnetNr = 6
	curSubnetNr = tcConf.General.ControlNodeCount + 1
}

func setLogLevel(logLevel *string) {
	//logLevel := flag.String("log", "", "logrus log level (debug, info, warn, error, fatal, panic)")
	logrus.SetFormatter(&logrus.TextFormatter{FullTimestamp: true})
	// parse string, this is built-in feature of logrus
	ll, err := logrus.ParseLevel(*logLevel)
	if err != nil {
		ll = logrus.InfoLevel
		logrus.Info("-log flag not provided, using default: ", ll)
	}
	// set global log level
	logrus.SetLevel(ll)
	//logrus.Info("Setting log level to ", ll)
}

func setConfigPath(configPath *string) {
	// if no --config argument given
	if *configPath == "" {
		err := flag.Set("config", configPath_default)
		if err != nil {
			logrus.Fatal(err)
		}
		logrus.Info("-config, -conf flag not provided, using default: ", *configPath)
	}
}

// needs the config file to be parsed to check the EKMS value.
func setEkmsNumber(ekmsNum *int) {
	if *ekmsNum < 1 {
		logrus.Info("-ekms, -kms flag not provided or invalid value, using value in config file: ", tcConf.EKMS.Num)
	} else {
		tcConf.EKMS.Num = *ekmsNum
		logrus.Info("EKMS number set to ", tcConf.EKMS.Num)
	}
}

func setPeerGenMode(mode *string) {
	if *mode == "" {
		err := flag.Set("mode", tcConf.PeerGen.Mode)
		if err != nil {
			logrus.Fatal(err)
		}
		peerGenMode = tcConf.PeerGen.Mode
		logrus.Info("-mode flag not provided, using value in config file: ", *mode)
	} else {
		tcConf.PeerGen.Mode = *mode
		peerGenMode = *mode
		logrus.Info("Peer generation mode set to ", peerGenMode)
	}
}