Added unit annotation supports onto tsmon in go.

common/tsmon/types/metricdataunits.go

+// Copyright 2016 The LUCI Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+package types
+
+import (
+        "fmt"
+
+        pb "github.com/luci/luci-go/common/tsmon/ts_mon_proto"
+)
+
+// MetricDataUnits are enums for the units of metrics data.
+type MetricDataUnits int32
+
+// Units of metrics data.
+const (
+        // NotSpecified is a magic value to skip Units property
+        // in a MetricsData proto message.
+        // Note that this should be defined with 0 so that all the existing
+        // codes without units specified would be given NotSpecified
+        // for the Units property automatically.
+        NotSpecified MetricDataUnits = iota
+        Unknown
+        Seconds
+        Milliseconds
+        Microseconds
+        Nanoseconds
+        Bits
+        Bytes
+
+        Kilobytes // 1000 bytes (not 1024).
+        Megabytes // 1e6 (1,000,000) bytes.
+        Gigabytes // 1e9 (1,000,000,000) bytes.
+        Kibibytes // 1024 bytes.
+        Mebibytes // 1024^2 (1,048,576) bytes.
+        Gibibytes // 1024^3 (1,073,741,824) bytes.
+
+        // * Extended Units
+        AmpUnit
+        MilliampUnit
+        DegreeCelsiusUnit
+)
+
+// IsSpecified returns true if a unit annotation has been specified
+// for a given metric.
+func (units MetricDataUnits) IsSpecified() bool {
+        return units != NotSpecified
+}
+
+// AsProto returns the protobuf representation of a given MetricDataUnits
+// object.
+func (units MetricDataUnits) AsProto() *pb.MetricsData_Units {
+        switch units {
+        case Unknown:
+                return pb.MetricsData_UNKNOWN_UNITS.Enum()
+        case Seconds:
+                return pb.MetricsData_SECONDS.Enum()
+        case Milliseconds:
+                return pb.MetricsData_MILLISECONDS.Enum()
+        case Microseconds:
+                return pb.MetricsData_MICROSECONDS.Enum()
+        case Nanoseconds:
+                return pb.MetricsData_NANOSECONDS.Enum()
+        case Bits:
+                return pb.MetricsData_BITS.Enum()
+        case Bytes:
+                return pb.MetricsData_BYTES.Enum()
+        case Kilobytes:
+                return pb.MetricsData_KILOBYTES.Enum()
+        case Megabytes:
+                return pb.MetricsData_MEGABYTES.Enum()
+        case Gigabytes:
+                return pb.MetricsData_GIGABYTES.Enum()
+        case Kibibytes:
+                return pb.MetricsData_KIBIBYTES.Enum()
+        case Mebibytes:
+                return pb.MetricsData_MEBIBYTES.Enum()
+        case Gibibytes:
+                return pb.MetricsData_GIBIBYTES.Enum()
+        case AmpUnit:
+                return pb.MetricsData_AMPS.Enum()
+        case MilliampUnit:
+                return pb.MetricsData_MILLIAMPS.Enum()
+        case DegreeCelsiusUnit:
+                return pb.MetricsData_DEGREES_CELSIUS.Enum()
+        }
+        panic(fmt.Sprintf("unknown MetricDataUnits %d", units))
+}