package line import ( "fmt" "strconv" "strings" "unicode/utf8" "github.com/go-kit/kit/log" "github.com/go-kit/kit/log/level" "github.com/prometheus/client_golang/prometheus" "github.com/prometheus/statsd_exporter/pkg/event" "github.com/prometheus/statsd_exporter/pkg/mapper" ) func buildEvent(statType, metric string, value float64, relative bool, labels map[string]string) (event.Event, error) { switch statType { case "c": return &event.CounterEvent{ CMetricName: metric, CValue: float64(value), CLabels: labels, }, nil case "g": return &event.GaugeEvent{ GMetricName: metric, GValue: float64(value), GRelative: relative, GLabels: labels, }, nil case "ms", "h", "d": return &event.TimerEvent{ TMetricName: metric, TValue: float64(value), TLabels: labels, }, nil case "s": return nil, fmt.Errorf("no support for StatsD sets") default: return nil, fmt.Errorf("bad stat type %s", statType) } } func parseTag(component, tag string, separator rune, labels map[string]string, tagErrors prometheus.Counter, logger log.Logger) { // Entirely empty tag is an error if len(tag) == 0 { tagErrors.Inc() level.Debug(logger).Log("msg", "Empty name tag", "component", component) return } for i, c := range tag { if c == separator { k := tag[:i] v := tag[i+1:] if len(k) == 0 || len(v) == 0 { // Empty key or value is an error tagErrors.Inc() level.Debug(logger).Log("msg", "Malformed name tag", "k", k, "v", v, "component", component) } else { labels[mapper.EscapeMetricName(k)] = v } return } } // Missing separator (no value) is an error tagErrors.Inc() level.Debug(logger).Log("msg", "Malformed name tag", "tag", tag, "component", component) } func parseNameTags(component string, labels map[string]string, tagErrors prometheus.Counter, logger log.Logger) { lastTagEndIndex := 0 for i, c := range component { if c == ',' { tag := component[lastTagEndIndex:i] lastTagEndIndex = i + 1 parseTag(component, tag, '=', labels, tagErrors, logger) } } // If we're not off the end of the string, add the last tag if lastTagEndIndex < len(component) { tag := component[lastTagEndIndex:] parseTag(component, tag, '=', labels, tagErrors, logger) } } func trimLeftHash(s string) string { if s != "" && s[0] == '#' { return s[1:] } return s } func ParseDogStatsDTags(component string, labels map[string]string, tagErrors prometheus.Counter, logger log.Logger) { lastTagEndIndex := 0 for i, c := range component { if c == ',' { tag := component[lastTagEndIndex:i] lastTagEndIndex = i + 1 parseTag(component, trimLeftHash(tag), ':', labels, tagErrors, logger) } } // If we're not off the end of the string, add the last tag if lastTagEndIndex < len(component) { tag := component[lastTagEndIndex:] parseTag(component, trimLeftHash(tag), ':', labels, tagErrors, logger) } } func parseNameAndTags(name string, labels map[string]string, tagErrors prometheus.Counter, logger log.Logger) string { for i, c := range name { // `#` delimits start of tags by Librato // https://www.librato.com/docs/kb/collect/collection_agents/stastd/#stat-level-tags // `,` delimits start of tags by InfluxDB // https://www.influxdata.com/blog/getting-started-with-sending-statsd-metrics-to-telegraf-influxdb/#introducing-influx-statsd if c == '#' || c == ',' { parseNameTags(name[i+1:], labels, tagErrors, logger) return name[:i] } } return name } func LineToEvents(line string, sampleErrors prometheus.CounterVec, samplesReceived prometheus.Counter, tagErrors prometheus.Counter, tagsReceived prometheus.Counter, logger log.Logger) event.Events { events := event.Events{} if line == "" { return events } elements := strings.SplitN(line, ":", 2) if len(elements) < 2 || len(elements[0]) == 0 || !utf8.ValidString(line) { sampleErrors.WithLabelValues("malformed_line").Inc() level.Debug(logger).Log("msg", "Bad line from StatsD", "line", line) return events } labels := map[string]string{} metric := parseNameAndTags(elements[0], labels, tagErrors, logger) var samples []string if strings.Contains(elements[1], "|#") { // using DogStatsD tags // don't allow mixed tagging styles if len(labels) > 0 { sampleErrors.WithLabelValues("mixed_tagging_styles").Inc() level.Debug(logger).Log("msg", "Bad line (multiple tagging styles) from StatsD", "line", line) return events } // disable multi-metrics samples = elements[1:] } else { samples = strings.Split(elements[1], ":") } samples: for _, sample := range samples { samplesReceived.Inc() components := strings.Split(sample, "|") samplingFactor := 1.0 if len(components) < 2 || len(components) > 4 { sampleErrors.WithLabelValues("malformed_component").Inc() level.Debug(logger).Log("msg", "Bad component", "line", line) continue } valueStr, statType := components[0], components[1] var relative = false if strings.Index(valueStr, "+") == 0 || strings.Index(valueStr, "-") == 0 { relative = true } value, err := strconv.ParseFloat(valueStr, 64) if err != nil { level.Debug(logger).Log("msg", "Bad value", "value", valueStr, "line", line) sampleErrors.WithLabelValues("malformed_value").Inc() continue } multiplyEvents := 1 if len(components) >= 3 { for _, component := range components[2:] { if len(component) == 0 { level.Debug(logger).Log("msg", "Empty component", "line", line) sampleErrors.WithLabelValues("malformed_component").Inc() continue samples } } for _, component := range components[2:] { switch component[0] { case '@': samplingFactor, err = strconv.ParseFloat(component[1:], 64) if err != nil { level.Debug(logger).Log("msg", "Invalid sampling factor", "component", component[1:], "line", line) sampleErrors.WithLabelValues("invalid_sample_factor").Inc() } if samplingFactor == 0 { samplingFactor = 1 } if statType == "g" { continue } else if statType == "c" { value /= samplingFactor } else if statType == "ms" || statType == "h" || statType == "d" { multiplyEvents = int(1 / samplingFactor) } case '#': ParseDogStatsDTags(component[1:], labels, tagErrors, logger) default: level.Debug(logger).Log("msg", "Invalid sampling factor or tag section", "component", components[2], "line", line) sampleErrors.WithLabelValues("invalid_sample_factor").Inc() continue } } } if len(labels) > 0 { tagsReceived.Inc() } for i := 0; i < multiplyEvents; i++ { event, err := buildEvent(statType, metric, value, relative, labels) if err != nil { level.Debug(logger).Log("msg", "Error building event", "line", line, "error", err) sampleErrors.WithLabelValues("illegal_event").Inc() continue } events = append(events, event) } } return events }