telegraf/plugins/inputs/redis/redis.go

289 lines
6.1 KiB
Go

package redis
import (
"bufio"
"errors"
"fmt"
"net"
"net/url"
"strconv"
"strings"
"sync"
"time"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/plugins/inputs"
)
type Redis struct {
Servers []string
}
var sampleConfig = `
## specify servers via a url matching:
## [protocol://][:password]@address[:port]
## e.g.
## tcp://localhost:6379
## tcp://:password@192.168.99.100
## unix:///var/run/redis.sock
##
## If no servers are specified, then localhost is used as the host.
## If no port is specified, 6379 is used
servers = ["tcp://localhost:6379"]
`
var defaultTimeout = 5 * time.Second
func (r *Redis) SampleConfig() string {
return sampleConfig
}
func (r *Redis) Description() string {
return "Read metrics from one or many redis servers"
}
var Tracking = map[string]string{
"uptime_in_seconds": "uptime",
"connected_clients": "clients",
"role": "replication_role",
}
var ErrProtocolError = errors.New("redis protocol error")
const defaultPort = "6379"
// Reads stats from all configured servers accumulates stats.
// Returns one of the errors encountered while gather stats (if any).
func (r *Redis) Gather(acc telegraf.Accumulator) error {
if len(r.Servers) == 0 {
url := &url.URL{
Scheme: "tcp",
Host: ":6379",
}
r.gatherServer(url, acc)
return nil
}
var wg sync.WaitGroup
for _, serv := range r.Servers {
if !strings.HasPrefix(serv, "tcp://") && !strings.HasPrefix(serv, "unix://") {
serv = "tcp://" + serv
}
u, err := url.Parse(serv)
if err != nil {
acc.AddError(fmt.Errorf("Unable to parse to address '%s': %s", serv, err))
continue
} else if u.Scheme == "" {
// fallback to simple string based address (i.e. "10.0.0.1:10000")
u.Scheme = "tcp"
u.Host = serv
u.Path = ""
}
if u.Scheme == "tcp" {
_, _, err := net.SplitHostPort(u.Host)
if err != nil {
u.Host = u.Host + ":" + defaultPort
}
}
wg.Add(1)
go func(serv string) {
defer wg.Done()
acc.AddError(r.gatherServer(u, acc))
}(serv)
}
wg.Wait()
return nil
}
func (r *Redis) gatherServer(addr *url.URL, acc telegraf.Accumulator) error {
var address string
if addr.Scheme == "unix" {
address = addr.Path
} else {
address = addr.Host
}
c, err := net.DialTimeout(addr.Scheme, address, defaultTimeout)
if err != nil {
return fmt.Errorf("Unable to connect to redis server '%s': %s", address, err)
}
defer c.Close()
// Extend connection
c.SetDeadline(time.Now().Add(defaultTimeout))
if addr.User != nil {
pwd, set := addr.User.Password()
if set && pwd != "" {
c.Write([]byte(fmt.Sprintf("AUTH %s\r\n", pwd)))
rdr := bufio.NewReader(c)
line, err := rdr.ReadString('\n')
if err != nil {
return err
}
if line[0] != '+' {
return fmt.Errorf("%s", strings.TrimSpace(line)[1:])
}
}
}
c.Write([]byte("INFO\r\n"))
c.Write([]byte("EOF\r\n"))
rdr := bufio.NewReader(c)
var tags map[string]string
if addr.Scheme == "unix" {
tags = map[string]string{"socket": addr.Path}
} else {
// Setup tags for all redis metrics
host, port := "unknown", "unknown"
// If there's an error, ignore and use 'unknown' tags
host, port, _ = net.SplitHostPort(addr.Host)
tags = map[string]string{"server": host, "port": port}
}
return gatherInfoOutput(rdr, acc, tags)
}
// gatherInfoOutput gathers
func gatherInfoOutput(
rdr *bufio.Reader,
acc telegraf.Accumulator,
tags map[string]string,
) error {
var section string
var keyspace_hits, keyspace_misses int64
scanner := bufio.NewScanner(rdr)
fields := make(map[string]interface{})
for scanner.Scan() {
line := scanner.Text()
if strings.Contains(line, "ERR") {
break
}
if len(line) == 0 {
continue
}
if line[0] == '#' {
if len(line) > 2 {
section = line[2:]
}
continue
}
parts := strings.SplitN(line, ":", 2)
if len(parts) < 2 {
continue
}
name := string(parts[0])
if section == "Server" {
if name != "lru_clock" && name != "uptime_in_seconds" && name != "redis_version" {
continue
}
}
if strings.HasPrefix(name, "master_replid") {
continue
}
if name == "mem_allocator" {
continue
}
if strings.HasSuffix(name, "_human") {
continue
}
metric, ok := Tracking[name]
if !ok {
if section == "Keyspace" {
kline := strings.TrimSpace(string(parts[1]))
gatherKeyspaceLine(name, kline, acc, tags)
continue
}
metric = name
}
val := strings.TrimSpace(parts[1])
// Try parsing as int
if ival, err := strconv.ParseInt(val, 10, 64); err == nil {
switch name {
case "keyspace_hits":
keyspace_hits = ival
case "keyspace_misses":
keyspace_misses = ival
case "rdb_last_save_time":
// influxdb can't calculate this, so we have to do it
fields["rdb_last_save_time_elapsed"] = time.Now().Unix() - ival
}
fields[metric] = ival
continue
}
// Try parsing as a float
if fval, err := strconv.ParseFloat(val, 64); err == nil {
fields[metric] = fval
continue
}
// Treat it as a string
if name == "role" {
tags["replication_role"] = val
continue
}
fields[metric] = val
}
var keyspace_hitrate float64 = 0.0
if keyspace_hits != 0 || keyspace_misses != 0 {
keyspace_hitrate = float64(keyspace_hits) / float64(keyspace_hits+keyspace_misses)
}
fields["keyspace_hitrate"] = keyspace_hitrate
acc.AddFields("redis", fields, tags)
return nil
}
// Parse the special Keyspace line at end of redis stats
// This is a special line that looks something like:
// db0:keys=2,expires=0,avg_ttl=0
// And there is one for each db on the redis instance
func gatherKeyspaceLine(
name string,
line string,
acc telegraf.Accumulator,
global_tags map[string]string,
) {
if strings.Contains(line, "keys=") {
fields := make(map[string]interface{})
tags := make(map[string]string)
for k, v := range global_tags {
tags[k] = v
}
tags["database"] = name
dbparts := strings.Split(line, ",")
for _, dbp := range dbparts {
kv := strings.Split(dbp, "=")
ival, err := strconv.ParseInt(kv[1], 10, 64)
if err == nil {
fields[kv[0]] = ival
}
}
acc.AddFields("redis_keyspace", fields, tags)
}
}
func init() {
inputs.Add("redis", func() telegraf.Input {
return &Redis{}
})
}