categraf/main.go

package main

import (
	"flag"
	"fmt"
	"log"
	"os"
	"os/signal"
	"strings"
	"syscall"

	"flashcat.cloud/categraf/agent"
	"flashcat.cloud/categraf/config"
	"flashcat.cloud/categraf/pkg/osx"
	"flashcat.cloud/categraf/writer"
	"github.com/toolkits/pkg/runner"
)

var (
	version      = "0.0.1"
	configDir    = flag.String("configs", osx.GetEnv("CATEGRAF_CONFIGS", "conf"), "Specify configuration directory.(env:CATEGRAF_CONFIGS)")
	debugMode    = flag.String("debug", osx.GetEnv("CATEGRAF_DEBUG", "false"), "Is debug mode?.(env:CATEGRAF_DEBUG)")
	testMode     = flag.Bool("test", false, "Is test mode? print metrics to stdout")
	showVersion  = flag.Bool("version", false, "Show version.")
	inputFilters = flag.String("input-filter", "", "e.g. cpu:mem:system")
)

func main() {
	flag.Parse()

	if *showVersion {
		fmt.Println(version)
		os.Exit(0)
	}

	printEnv()

	// init configs
	if err := config.InitConfig(*configDir, *debugMode, *testMode); err != nil {
		log.Println("F! failed to init config:", err)
		os.Exit(1)
	}

	// init writers
	if err := writer.Init(config.Config.Writers); err != nil {
		log.Println("F! failed to init writer:", err)
		os.Exit(1)
	}

	ag := agent.NewAgent(parseFilter(*inputFilters))
	ag.Start()

	handleSignal(ag)
}

func handleSignal(ag *agent.Agent) {
	sc := make(chan os.Signal, 1)
	signal.Notify(sc, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM, syscall.SIGQUIT)

EXIT:
	for {
		sig := <-sc
		log.Println("I! received signal:", sig.String())
		switch sig {
		case syscall.SIGQUIT, syscall.SIGTERM, syscall.SIGINT:
			break EXIT
		case syscall.SIGHUP:
			ag.Reload()
		default:
			break EXIT
		}
	}

	log.Println("I! exited")
}

func printEnv() {
	runner.Init()
	log.Println("I! runner.binarydir:", runner.Cwd)
	log.Println("I! runner.hostname:", runner.Hostname)
	log.Println("I! runner.fd_limits:", runner.FdLimits())
	log.Println("I! runner.vm_limits:", runner.VMLimits())
}

func parseFilter(filterStr string) map[string]struct{} {
	filters := strings.Split(filterStr, ":")
	filtermap := make(map[string]struct{})
	for i := 0; i < len(filters); i++ {
		if strings.TrimSpace(filters[i]) == "" {
			continue
		}
		filtermap[filters[i]] = struct{}{}
	}
	return filtermap
}