open-nomad/nomad/util.go
2016-06-10 15:48:36 -04:00

135 lines
2.8 KiB
Go

package nomad
import (
"fmt"
"math"
"math/big"
"math/rand"
"net"
"os"
"path/filepath"
"runtime"
"strconv"
"time"
crand "crypto/rand"
"github.com/hashicorp/serf/serf"
)
// ensurePath is used to make sure a path exists
func ensurePath(path string, dir bool) error {
if !dir {
path = filepath.Dir(path)
}
return os.MkdirAll(path, 0755)
}
// RuntimeStats is used to return various runtime information
func RuntimeStats() map[string]string {
return map[string]string{
"kernel.name": runtime.GOOS,
"arch": runtime.GOARCH,
"version": runtime.Version(),
"max_procs": strconv.FormatInt(int64(runtime.GOMAXPROCS(0)), 10),
"goroutines": strconv.FormatInt(int64(runtime.NumGoroutine()), 10),
"cpu_count": strconv.FormatInt(int64(runtime.NumCPU()), 10),
}
}
// serverParts is used to return the parts of a server role
type serverParts struct {
Name string
Region string
Datacenter string
Port int
Bootstrap bool
Expect int
Version int
Addr net.Addr
}
func (s *serverParts) String() string {
return fmt.Sprintf("%s (Addr: %s) (DC: %s)",
s.Name, s.Addr, s.Datacenter)
}
// Returns if a member is a Nomad server. Returns a boolean,
// and a struct with the various important components
func isNomadServer(m serf.Member) (bool, *serverParts) {
if m.Tags["role"] != "nomad" {
return false, nil
}
region := m.Tags["region"]
datacenter := m.Tags["dc"]
_, bootstrap := m.Tags["bootstrap"]
expect := 0
expect_str, ok := m.Tags["expect"]
var err error
if ok {
expect, err = strconv.Atoi(expect_str)
if err != nil {
return false, nil
}
}
port_str := m.Tags["port"]
port, err := strconv.Atoi(port_str)
if err != nil {
return false, nil
}
vsn_str := m.Tags["vsn"]
vsn, err := strconv.Atoi(vsn_str)
if err != nil {
return false, nil
}
addr := &net.TCPAddr{IP: m.Addr, Port: port}
parts := &serverParts{
Name: m.Name,
Region: region,
Datacenter: datacenter,
Port: port,
Bootstrap: bootstrap,
Expect: expect,
Addr: addr,
Version: vsn,
}
return true, parts
}
// Returns a random stagger interval between 0 and the duration
func randomStagger(intv time.Duration) time.Duration {
return time.Duration(uint64(rand.Int63()) % uint64(intv))
}
// shuffleStrings randomly shuffles the list of strings
func shuffleStrings(list []string) {
for i := range list {
j := rand.Intn(i + 1)
list[i], list[j] = list[j], list[i]
}
}
// maxUint64 returns the maximum value
func maxUint64(a, b uint64) uint64 {
if a >= b {
return a
}
return b
}
// seedRandom seeds the global random variable using a cryptographically random
// seed. It returns an error if determing the random seed fails.
func seedRandom() error {
n, err := crand.Int(crand.Reader, big.NewInt(math.MaxInt64))
if err != nil {
return err
}
rand.Seed(n.Int64())
return nil
}