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
|
package tb
import (
"io"
"log"
"net"
"strconv"
"testing"
"time"
)
func TestThrottler_Bucket(t *testing.T) {
t.Parallel()
th := NewThrottler(0)
defer th.Close()
b := th.Bucket("a", 1000)
ex := [...]int64{100, 100, 1000, 900, 1, 0}
for i := 0; i < len(ex)-1; i += 2 {
if got, want := b.Take(ex[i]), ex[i+1]; got != want {
t.Errorf("Want: %d, Got: %d", want, got)
}
}
for i := 0; i < len(ex)-1; i += 2 {
if got, want := b.Put(ex[i]), ex[i+1]; got != want {
t.Errorf("Want: %d, Got: %d", want, got)
}
}
}
func TestThrottler_Halt(t *testing.T) {
t.Parallel()
th := NewThrottler(0)
defer th.Close()
if th.Halt("a", 1000, 1000) {
t.Fatal("Didn't expect halt")
}
if !th.Halt("a", 1, 1000) {
t.Fatal("Expected halt")
}
if th.Halt("b", 1000, 1000) {
t.Fatal("Didn't expect halt")
}
}
func TestThrottler_Wait(t *testing.T) {
t.Parallel()
th := NewThrottler(1 * time.Millisecond)
defer th.Close()
if wait := th.Wait("a", 1000, 1000); wait > 0 {
t.Fatal("Didn't expect wait")
}
if wait := th.Wait("a", 2000, 1000); int(wait.Seconds()) != 2 {
t.Fatalf("Expected wait of 2s. Got: %s", wait)
}
}
func BenchmarkThrottler_Bucket(b *testing.B) {
keys := make([]string, 10000)
for i := 0; i < len(keys); i++ {
keys[i] = strconv.Itoa(i)
}
th := NewThrottler(1 * time.Millisecond)
defer th.Close()
b.ResetTimer()
for i := 0; i < b.N; i++ {
th.Bucket(keys[i%(len(keys)-1)], 1000)
}
}
func ExampleThrottler() {
ln, err := net.Listen("tcp", ":6789")
if err != nil {
log.Fatal(err)
}
th := NewThrottler(100 * time.Millisecond)
defer th.Close()
echo := func(conn net.Conn) {
defer conn.Close()
host, port, err := net.SplitHostPort(conn.RemoteAddr().String())
if err != nil {
panic(err)
}
// Throttle to 10 connection per second from the same host
// Handle non-conformity by dropping the connection
if th.Halt(host, 1, 10) {
log.Printf("Throttled %s", host)
return
}
log.Printf("Echoing payload from %s:%s", host, port)
io.Copy(conn, conn)
}
for {
conn, err := ln.Accept()
if err != nil {
log.Fatal(err)
}
go echo(conn)
}
}
|
