/
statsd.go
137 lines (118 loc) · 3.56 KB
/
statsd.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
// Copyright 2018 Twitch Interactive, Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License"). You may not
// use this file except in compliance with the License. A copy of the License is
// located at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// or in the "license" file accompanying this file. This file is distributed on
// an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
// express or implied. See the License for the specific language governing
// permissions and limitations under the License.
package statsd
import (
"context"
"strings"
"time"
"github.com/twitchtv/twirp"
)
var reqStartTimestampKey = new(int)
func markReqStart(ctx context.Context) context.Context {
return context.WithValue(ctx, reqStartTimestampKey, time.Now())
}
func getReqStart(ctx context.Context) (time.Time, bool) {
t, ok := ctx.Value(reqStartTimestampKey).(time.Time)
return t, ok
}
type Statter interface {
Inc(metric string, val int64, rate float32) error
TimingDuration(metric string, val time.Duration, rate float32) error
}
// NewStatsdServerHooks provides a twirp.ServerHooks struct which
// sends data to statsd.
func NewStatsdServerHooks(stats Statter) *twirp.ServerHooks {
hooks := &twirp.ServerHooks{}
// RequestReceived: inc twirp.total.req_recv
hooks.RequestReceived = func(ctx context.Context) (context.Context, error) {
ctx = markReqStart(ctx)
stats.Inc("twirp.total.requests", 1, 1.0)
return ctx, nil
}
// RequestRouted: inc twirp.<method>.req_recv
hooks.RequestRouted = func(ctx context.Context) (context.Context, error) {
method, ok := twirp.MethodName(ctx)
if !ok {
return ctx, nil
}
stats.Inc("twirp."+sanitize(method)+".requests", 1, 1.0)
return ctx, nil
}
// ResponseSent:
// - inc twirp.total.responses
// - inc twirp.<method>.responses
// - inc twirp.status_codes.total.<code>
// - inc twirp.status_codes.<method>.<code>
// - time twirp.all_methods.response
// - time twirp.<method>.response
// - time twirp.status_codes.all_methods.<code>
// - time twirp.status_codes.<method>.<code>
hooks.ResponseSent = func(ctx context.Context) {
// Three pieces of data to get, none are guaranteed to be present:
// - time that the request started
// - method that was called
// - status code of response
var (
start time.Time
method string
status string
haveStart bool
haveMethod bool
haveStatus bool
)
start, haveStart = getReqStart(ctx)
method, haveMethod = twirp.MethodName(ctx)
status, haveStatus = twirp.StatusCode(ctx)
method = sanitize(method)
status = sanitize(status)
stats.Inc("twirp.total.responses", 1, 1.0)
if haveMethod {
stats.Inc("twirp."+method+".responses", 1, 1.0)
}
if haveStatus {
stats.Inc("twirp.status_codes.total."+status, 1, 1.0)
}
if haveMethod && haveStatus {
stats.Inc("twirp.status_codes."+method+"."+status, 1, 1.0)
}
if haveStart {
dur := time.Now().Sub(start)
stats.TimingDuration("twirp.all_methods.response", dur, 1.0)
if haveMethod {
stats.TimingDuration("twirp."+method+".response", dur, 1.0)
}
if haveStatus {
stats.TimingDuration("twirp.status_codes.all_methods."+status, dur, 1.0)
}
if haveMethod && haveStatus {
stats.TimingDuration("twirp.status_codes."+method+"."+status, dur, 1.0)
}
}
}
return hooks
}
func sanitize(s string) string {
return strings.Map(sanitizeRune, s)
}
func sanitizeRune(r rune) rune {
switch {
case 'a' <= r && r <= 'z':
return r
case '0' <= r && r <= '9':
return r
case 'A' <= r && r <= 'Z':
return r
default:
return '_'
}
}