Added unit annotation supports onto tsmon in go.

appengine/tsmon/grpc.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 tsmon
 
 import (
         "time"
 
         "golang.org/x/net/context"
         "google.golang.org/grpc"
 
         "github.com/luci/luci-go/common/clock"
         "github.com/luci/luci-go/common/tsmon/distribution"
         "github.com/luci/luci-go/common/tsmon/field"
         "github.com/luci/luci-go/common/tsmon/metric"
+        "github.com/luci/luci-go/common/tsmon/types"
 )
 
 var (
         grpcServerCount = metric.NewCounter(
                 "grpc/server/count",
                 "Total number of RPCs.",
+                types.MetricMetadata{},
                 field.String("method"), // full name of the grpc method
                 field.Int("code"))      // grpc.Code of the result
 
         grpcServerDuration = metric.NewCumulativeDistribution(
                 "grpc/server/duration",
                 "Distribution of server-side RPC duration (in milliseconds).",
+                types.MetricMetadata{},
                 distribution.DefaultBucketer,
                 field.String("method"), // full name of the grpc method
                 field.Int("code"))      // grpc.Code of the result
 )
 
 // NewGrpcUnaryInterceptor returns an interceptor that gathers RPC handler
 // metrics and sends them to tsmon.
 //
 // It can be optionally chained with other interceptor. The reported metrics
 // include time spent in this other interceptor too.
@@ skipping 15 matching lines @@
 
 // reportRPCMetrics sends metrics after RPC handler has finished.
 func reportRPCMetrics(ctx context.Context, method string, err error, dur time.Duration) {
         code := 0
         if err != nil {
                 code = int(grpc.Code(err))
         }
         grpcServerCount.Add(ctx, 1, method, code)
         grpcServerDuration.Add(ctx, float64(dur.Nanoseconds()/1000000), method, code)
 }