telegraf/plugins/inputs/redis/redis.go

266 lines
6.5 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
##
## 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",
"used_memory": "used_memory",
"used_memory_rss": "used_memory_rss",
"used_memory_peak": "used_memory_peak",
"used_memory_lua": "used_memory_lua",
"rdb_changes_since_last_save": "rdb_changes_since_last_save",
"total_connections_received": "total_connections_received",
"total_commands_processed": "total_commands_processed",
"instantaneous_ops_per_sec": "instantaneous_ops_per_sec",
"instantaneous_input_kbps": "instantaneous_input_kbps",
"instantaneous_output_kbps": "instantaneous_output_kbps",
"sync_full": "sync_full",
"sync_partial_ok": "sync_partial_ok",
"sync_partial_err": "sync_partial_err",
"expired_keys": "expired_keys",
"evicted_keys": "evicted_keys",
"keyspace_hits": "keyspace_hits",
"keyspace_misses": "keyspace_misses",
"pubsub_channels": "pubsub_channels",
"pubsub_patterns": "pubsub_patterns",
"latest_fork_usec": "latest_fork_usec",
"connected_slaves": "connected_slaves",
"master_repl_offset": "master_repl_offset",
"repl_backlog_active": "repl_backlog_active",
"repl_backlog_size": "repl_backlog_size",
"repl_backlog_histlen": "repl_backlog_histlen",
"mem_fragmentation_ratio": "mem_fragmentation_ratio",
"used_cpu_sys": "used_cpu_sys",
"used_cpu_user": "used_cpu_user",
"used_cpu_sys_children": "used_cpu_sys_children",
"used_cpu_user_children": "used_cpu_user_children",
"role": "role",
}
var ErrProtocolError = errors.New("redis protocol error")
// 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{
Host: ":6379",
}
r.gatherServer(url, acc)
return nil
}
var wg sync.WaitGroup
var outerr error
for _, serv := range r.Servers {
u, err := url.Parse(serv)
if err != nil {
return fmt.Errorf("Unable to parse to address '%s': %s", serv, err)
} 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 = ""
}
wg.Add(1)
go func(serv string) {
defer wg.Done()
outerr = r.gatherServer(u, acc)
}(serv)
}
wg.Wait()
return outerr
}
const defaultPort = "6379"
func (r *Redis) gatherServer(addr *url.URL, acc telegraf.Accumulator) error {
_, _, err := net.SplitHostPort(addr.Host)
if err != nil {
addr.Host = addr.Host + ":" + defaultPort
}
c, err := net.DialTimeout("tcp", addr.Host, defaultTimeout)
if err != nil {
return fmt.Errorf("Unable to connect to redis server '%s': %s", addr.Host, 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)
// 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 keyspace_hits, keyspace_misses uint64 = 0, 0
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 || line[0] == '#' {
continue
}
parts := strings.SplitN(line, ":", 2)
if len(parts) < 2 {
continue
}
name := string(parts[0])
metric, ok := Tracking[name]
if !ok {
kline := strings.TrimSpace(string(parts[1]))
gatherKeyspaceLine(name, kline, acc, tags)
continue
}
val := strings.TrimSpace(parts[1])
ival, err := strconv.ParseUint(val, 10, 64)
if name == "keyspace_hits" {
keyspace_hits = ival
}
if name == "keyspace_misses" {
keyspace_misses = ival
}
if name == "role" {
tags["role"] = val
continue
}
if err == nil {
fields[metric] = ival
continue
}
fval, err := strconv.ParseFloat(val, 64)
if err != nil {
return err
}
fields[metric] = fval
}
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,
tags map[string]string,
) {
if strings.Contains(line, "keys=") {
fields := make(map[string]interface{})
tags["database"] = name
dbparts := strings.Split(line, ",")
for _, dbp := range dbparts {
kv := strings.Split(dbp, "=")
ival, err := strconv.ParseUint(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{}
})
}