terraform/command/testdata/statelocker.go

// statelocker use used for testing command with a locked state.
// This will lock the state file at a given path, then wait for a sigal. On
// SIGINT and SIGTERM the state will be Unlocked before exit.
package main

import (
	"io"
	"log"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/hashicorp/terraform/state"
)

func main() {
	if len(os.Args) != 2 {
		log.Fatal(os.Args[0], "statefile")
	}

	s := &state.LocalState{
		Path: os.Args[1],
	}

	lockID, err := s.Lock(&state.LockInfo{Operation: "test", Info: "state locker"})
	if err != nil {
		io.WriteString(os.Stderr, err.Error())
		return
	}

	// signal to the caller that we're locked
	io.WriteString(os.Stdout, "LOCKED")

	defer func() {
		if err := s.Unlock(lockID); err != nil {
			io.WriteString(os.Stderr, err.Error())
		}
	}()

	c := make(chan os.Signal, 1)
	signal.Notify(c, syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)

	// timeout after 10 second in case we don't get cleaned up by the test
	select {
	case <-time.After(10 * time.Second):
	case <-c:
	}
}