wait.go

package main

import (
	"fmt"
	"log"
	"time"

	"github.com/DarkDNA/vultr"
)

type retStruct struct {
	err  error
	info *vultr.Server
}

// waitForState simply blocks until the droplet is in
// a state we expect, while eventually timing out.
func waitForServerState(state string, power string, serverId string, client *vultr.Client, timeout time.Duration) (*vultr.Server, error) {
	done := make(chan struct{})
	defer close(done)
	result := make(chan retStruct, 1)
	go func() {
		attempts := 0
		for {
			attempts += 1
			log.Printf("Checking server status... (attempt: %d)", attempts)
			serverInfo, err := client.GetServer(serverId)
			if err != nil {
				result <- retStruct{err, nil}
				return
			}
			if serverInfo.Status == state && (serverInfo.Power == power || power == "") {
				result <- retStruct{nil, serverInfo}
				return
			}

			// Wait 3 seconds in between
			time.Sleep(3 * time.Second)

			// Verify we shouldn't exit
			select {
			case <-done:
				// We finished, so just exit the goroutine
				return
			default:
				// Keep going
			}
		}
	}()
	log.Printf("Waiting for up to %d seconds for server", timeout/time.Second)
	select {
	case retval := <-result:
		return retval.info, retval.err
	case <-time.After(timeout):
		err := fmt.Errorf("Timeout while waiting to for server")
		return nil, err
	}
}
func waitForSnapshotState(state string, snapshotId string, client *vultr.Client, timeout time.Duration) error {
	done := make(chan struct{})
	defer close(done)
	result := make(chan error, 1)
	go func() {
		attempts := 0
		for {
			attempts += 1
			log.Printf("Checking snapshot status... (attempt: %d)", attempts)
			snapshotInfo, err := client.GetSnapshot(snapshotId)
			if err != nil {
				result <- err
				return
			}
			if snapshotInfo.Status == state {
				result <- nil
				return
			}

			// Wait 3 seconds in between
			time.Sleep(3 * time.Second)

			// Verify we shouldn't exit
			select {
			case <-done:
				// We finished, so just exit the goroutine
				return
			default:
				// Keep going
			}
		}
	}()
	log.Printf("Waiting for up to %d seconds for snapshot", timeout/time.Second)
	select {
	case retval := <-result:
		return retval
	case <-time.After(timeout):
		err := fmt.Errorf("Timeout while waiting to for snapshot")
		return err
	}
}