circolog/cmd/circologctl/main.go

package main

import (
	"context"
	"flag"
	"fmt"
	"io"
	"io/ioutil"
	"net"
	"net/http"
	"os"
	"strconv"
	"strings"
)

var globalOpts struct {
	ctlSock string
	verbose bool
}

var ctl http.Client

type commandFunc func([]string) error

var cmdMap map[string]commandFunc

func init() {
	cmdMap = map[string]commandFunc{
		// TODO: implement set and get of config at runtime
		//"set":     setCmd,
		//"get":     getCmd,
		"pause":   pauseCmd,
		"reload":  reloadCmd,
		"restart": restartCmd,
		"help":    helpCmd,
	}
}

//func setCmd(ctlSock string, args []string) error {}

//func getCmd(ctlSock string, args []string) error {}

func parsePauseOpts(postponeTime string) (string, error) {
	var waitTime int64
	var err error
	L := len(postponeTime)
	switch unit := postponeTime[L-1]; string(unit) {
	case "s":
		waitTime, err = strconv.ParseInt(postponeTime[:L-2], 10, 16)
		if err != nil {
			return "", err
		}
	case "m":
		waitTime, err = strconv.ParseInt(postponeTime[:L-2], 10, 16)
		if err != nil {
			return "", err
		}
		waitTime = waitTime * 60
	case "h":
		waitTime, err = strconv.ParseInt(postponeTime[:L-2], 10, 16)
		if err != nil {
			return "", err
		}
		waitTime = waitTime * 60 * 60
	case "d":
		waitTime, err = strconv.ParseInt(postponeTime[:L-2], 10, 16)
		if err != nil {
			return "", err
		}
		waitTime = waitTime * 60 * 60 * 24
	case "w":
		waitTime, err = strconv.ParseInt(postponeTime[:L-2], 10, 16)
		if err != nil {
			return "", err
		}
		waitTime = waitTime * 60 * 60 * 24 * 7
	}
	return string(waitTime), nil
}

func pauseCmd(args []string) error {
	var postBody string
	var err error
	flagset := flag.NewFlagSet(args[0], flag.ExitOnError)
	postponeTime := flagset.String("postpone", "", "How long to wait before untoggling the state")
	flagset.Parse(args[1:])
	if *postponeTime != "" {
		postBody, err = parsePauseOpts(*postponeTime)
		if err != nil {
			return err
		}
	}
	resp, err := ctl.Post("http://unix/pause/toggle", "application/octet-stream", strings.NewReader(postBody))
	if globalOpts.verbose {
		defer resp.Body.Close()
		bodyBytes, err2 := ioutil.ReadAll(resp.Body)
		if err2 != nil {
			return err2
		}
		fmt.Println(string(bodyBytes))
	}
	return err
}

func reloadCmd(args []string) error {
	return nil
}

func restartCmd(args []string) error {
	return nil
}

func helpCmd(args []string) error {
	usage(os.Stdout)
	os.Exit(0)
	return nil
}

func usage(w io.Writer) {
	fmt.Fprintf(w, "USAGE: %s [globalOpts] [SUBCOMMAND] [opts]\n", os.Args[0])
	fmt.Fprintf(w, "\nSUBCOMMANDS:\n\n")
	for command := range cmdMap {
		fmt.Fprintf(w, "\t%s\n", command)
	}
}

func parseAndRun(args []string) {
	cmdName := args[0]
	cmdToRun, ok := cmdMap[cmdName]
	if !ok {
		fmt.Fprintf(os.Stderr, "Unknown subcommand: %s\n", cmdName)
		usage(os.Stderr)
		os.Exit(2)
	}
	// from here: https://gist.github.com/teknoraver/5ffacb8757330715bcbcc90e6d46ac74
	ctl = http.Client{
		Transport: &http.Transport{
			DialContext: func(_ context.Context, _, _ string) (net.Conn, error) {
				return net.Dial("unix", globalOpts.ctlSock)
			},
		},
	}
	err := cmdToRun(args)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error:\n%s\n", err)
		os.Exit(1)
	}
}

func main() {
	flag.StringVar(&globalOpts.ctlSock, "ctl-socket", "/tmp/circologd-ctl.sock",
		"Path to a unix domain socket for the control server; leave empty to disable")
	flag.BoolVar(&globalOpts.verbose, "verbose", false, "Print more output")
	flag.Parse()
	args := flag.Args()
	if len(args) == 0 {
		usage(os.Stderr)
		os.Exit(-1)
	}
	parseAndRun(args)
}