Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/serializers/prometheus/convert.go

@@ -0,0 +1,197 @@
+package prometheus
+
+import (
+	"strings"
+	"unicode"
+
+	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/model"
+
+	"github.com/influxdata/telegraf"
+)
+
+type Table struct {
+	First *unicode.RangeTable
+	Rest  *unicode.RangeTable
+}
+
+var MetricNameTable = Table{
+	First: &unicode.RangeTable{
+		R16: []unicode.Range16{
+			{0x003A, 0x003A, 1}, // :
+			{0x0041, 0x005A, 1}, // A-Z
+			{0x005F, 0x005F, 1}, // _
+			{0x0061, 0x007A, 1}, // a-z
+		},
+		LatinOffset: 4,
+	},
+	Rest: &unicode.RangeTable{
+		R16: []unicode.Range16{
+			{0x0030, 0x003A, 1}, // 0-:
+			{0x0041, 0x005A, 1}, // A-Z
+			{0x005F, 0x005F, 1}, // _
+			{0x0061, 0x007A, 1}, // a-z
+		},
+		LatinOffset: 4,
+	},
+}
+
+var LabelNameTable = Table{
+	First: &unicode.RangeTable{
+		R16: []unicode.Range16{
+			{0x0041, 0x005A, 1}, // A-Z
+			{0x005F, 0x005F, 1}, // _
+			{0x0061, 0x007A, 1}, // a-z
+		},
+		LatinOffset: 3,
+	},
+	Rest: &unicode.RangeTable{
+		R16: []unicode.Range16{
+			{0x0030, 0x0039, 1}, // 0-9
+			{0x0041, 0x005A, 1}, // A-Z
+			{0x005F, 0x005F, 1}, // _
+			{0x0061, 0x007A, 1}, // a-z
+		},
+		LatinOffset: 4,
+	},
+}
+
+// Sanitize checks if the name is valid according to the table.  If not, it
+// attempts to replaces invalid runes with an underscore to create a valid
+// name.
+func sanitize(name string, table Table) (string, bool) {
+	var b strings.Builder
+
+	for i, r := range name {
+		switch i {
+		case 0:
+			if unicode.In(r, table.First) {
+				b.WriteRune(r)
+			}
+		default:
+			if unicode.In(r, table.Rest) {
+				b.WriteRune(r)
+			} else {
+				b.WriteString("_")
+			}
+		}
+	}
+
+	name = strings.Trim(b.String(), "_")
+	if name == "" {
+		return "", false
+	}
+	return name, true
+}
+
+// SanitizeMetricName checks if the name is a valid Prometheus metric name.  If
+// not, it attempts to replaces invalid runes with an underscore to create a
+// valid name.
+func SanitizeMetricName(name string) (string, bool) {
+	if model.IsValidLegacyMetricName(name) {
+		return name, true
+	}
+	return sanitize(name, MetricNameTable)
+}
+
+// SanitizeLabelName checks if the name is a valid Prometheus label name.  If
+// not, it attempts to replaces invalid runes with an underscore to create a
+// valid name.
+func SanitizeLabelName(name string) (string, bool) {
+	if model.LabelName(name).IsValidLegacy() {
+		return name, true
+	}
+	return sanitize(name, LabelNameTable)
+}
+
+// MetricName returns the Prometheus metric name.
+func MetricName(measurement, fieldKey string, valueType telegraf.ValueType) string {
+	switch valueType {
+	case telegraf.Histogram, telegraf.Summary:
+		switch {
+		case strings.HasSuffix(fieldKey, "_bucket"):
+			fieldKey = strings.TrimSuffix(fieldKey, "_bucket")
+		case strings.HasSuffix(fieldKey, "_sum"):
+			fieldKey = strings.TrimSuffix(fieldKey, "_sum")
+		case strings.HasSuffix(fieldKey, "_count"):
+			fieldKey = strings.TrimSuffix(fieldKey, "_count")
+		}
+	}
+
+	if measurement == "prometheus" {
+		return fieldKey
+	}
+	return measurement + "_" + fieldKey
+}
+
+func MetricType(valueType telegraf.ValueType) *dto.MetricType {
+	switch valueType {
+	case telegraf.Counter:
+		return dto.MetricType_COUNTER.Enum()
+	case telegraf.Gauge:
+		return dto.MetricType_GAUGE.Enum()
+	case telegraf.Summary:
+		return dto.MetricType_SUMMARY.Enum()
+	case telegraf.Untyped:
+		return dto.MetricType_UNTYPED.Enum()
+	case telegraf.Histogram:
+		return dto.MetricType_HISTOGRAM.Enum()
+	default:
+		panic("unknown telegraf.ValueType")
+	}
+}
+
+// SampleValue converts a field value into a value suitable for a simple sample value.
+func SampleValue(value interface{}) (float64, bool) {
+	switch v := value.(type) {
+	case float64:
+		return v, true
+	case int64:
+		return float64(v), true
+	case uint64:
+		return float64(v), true
+	case bool:
+		if v {
+			return 1.0, true
+		}
+		return 0.0, true
+	default:
+		return 0, false
+	}
+}
+
+// SampleCount converts a field value into a count suitable for a metric family
+// of the Histogram or Summary type.
+func SampleCount(value interface{}) (uint64, bool) {
+	switch v := value.(type) {
+	case float64:
+		if v < 0 {
+			return 0, false
+		}
+		return uint64(v), true
+	case int64:
+		if v < 0 {
+			return 0, false
+		}
+		return uint64(v), true
+	case uint64:
+		return v, true
+	default:
+		return 0, false
+	}
+}
+
+// SampleSum converts a field value into a sum suitable for a metric family
+// of the Histogram or Summary type.
+func SampleSum(value interface{}) (float64, bool) {
+	switch v := value.(type) {
+	case float64:
+		return v, true
+	case int64:
+		return float64(v), true
+	case uint64:
+		return float64(v), true
+	default:
+		return 0, false
+	}
+}