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 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{} }) }