zfs_replication_exporter/zfs_replication_exporter.go

124 lines
3.0 KiB
Go

package main
import (
"bufio"
"bytes"
"flag"
"fmt"
"io/ioutil"
"os"
"path/filepath"
"regexp"
"time"
"github.com/golang/glog"
"golang.org/x/crypto/ssh"
)
var (
host = flag.String("host", "localhost:22", "host:port to scp from")
user = flag.String("user", os.Getenv("USER"), "ssh user")
)
// Example: @auto-20171001.1400-2w
var (
snapshotPattern = regexp.MustCompile(`^([^@]+)@auto-(\d{8}\.\d{4})-\d+[mwy]$`)
snapshotFormat = "20060102.1504"
)
func newPublicKey() ([]ssh.AuthMethod, error) {
var signers []ssh.AuthMethod
for _, path := range []string{
filepath.Join(os.Getenv("HOME"), ".ssh", "id_dsa"),
filepath.Join(os.Getenv("HOME"), ".ssh", "id_rsa"),
} {
// A public key may be used to authenticate against the remote
// server by using an unencrypted PEM-encoded private key file.
//
// If you have an encrypted private key, the crypto/x509 package
// can be used to decrypt it.
key, err := ioutil.ReadFile(path)
if err != nil {
if os.IsNotExist(err) {
continue
}
return nil, fmt.Errorf("unable to read private key %q: %v", path, err)
}
// Create the Signer for this private key.
signer, err := ssh.ParsePrivateKey(key)
if err != nil {
return nil, fmt.Errorf("unable to parse private key %q: %v", path, err)
}
signers = append(signers, ssh.PublicKeys(signer))
}
if len(signers) == 0 {
return nil, fmt.Errorf("no public keys configured")
}
return signers, nil
}
func main() {
flag.Parse()
defer glog.Flush()
ams, err := newPublicKey()
if err != nil {
glog.Exitf("Error fetching public keys: %v", err)
}
// An SSH client is represented with a ClientConn.
//
// To authenticate with the remote server you must pass at least one
// implementation of ClientAuth via the Auth field in ClientConfig.
config := &ssh.ClientConfig{
User: *user,
Auth: ams,
// TODO(wathiede); use FixedHostKey?
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}
client, err := ssh.Dial("tcp", *host, config)
if err != nil {
glog.Exitf("Error dialing %q: %v", *host, err)
}
// Each ClientConn can support multiple interactive sessions,
// represented by a Session.
s, err := client.NewSession()
if err != nil {
glog.Exitf("Error creating new session: %v", err)
}
cmd := "/sbin/zfs list -t snapshot -H -o name -s name"
b, err := s.CombinedOutput(cmd)
if err != nil {
glog.Exitf("Error running %q: %v", cmd, err)
}
scanner := bufio.NewScanner(bytes.NewReader(b))
snapshotAges := map[string]time.Time{}
for scanner.Scan() {
l := scanner.Text()
m := snapshotPattern.FindStringSubmatch(l)
if len(m) == 3 {
snapshot := m[1]
t, err := time.Parse(snapshotFormat, m[2])
if err != nil {
glog.Errorf("Malformed time in snapshot %q: %v", m[2], err)
continue
}
snapshotTime := snapshotAges[snapshot]
if snapshotTime.Before(t) {
snapshotAges[snapshot] = t
}
}
}
if err := scanner.Err(); err != nil {
glog.Exitf("Failed to scan response: %v", err)
}
for snapshot, snapshotTime := range snapshotAges {
fmt.Println(snapshot, snapshotTime, time.Since(snapshotTime))
}
}