forked from redpanda-data/connect
-
Notifications
You must be signed in to change notification settings - Fork 0
/
fan_in.go
129 lines (105 loc) · 3.62 KB
/
fan_in.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
// Copyright (c) 2014 Ashley Jeffs
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package broker
import (
"time"
"github.com/Jeffail/benthos/lib/types"
"github.com/Jeffail/benthos/lib/util/service/metrics"
)
//------------------------------------------------------------------------------
// FanIn is a broker that implements types.Producer, takes an array of inputs
// and routes them through a single message channel.
type FanIn struct {
stats metrics.Type
transactions chan types.Transaction
closables []types.Closable
inputClosedChan chan int
inputMap map[int]struct{}
closedChan chan struct{}
}
// NewFanIn creates a new FanIn type by providing inputs.
func NewFanIn(inputs []types.Producer, stats metrics.Type) (*FanIn, error) {
i := &FanIn{
stats: stats,
transactions: make(chan types.Transaction),
inputClosedChan: make(chan int),
inputMap: make(map[int]struct{}),
closables: []types.Closable{},
closedChan: make(chan struct{}),
}
for n, input := range inputs {
if closable, ok := input.(types.Closable); ok {
i.closables = append(i.closables, closable)
}
// Keep track of # open inputs
i.inputMap[n] = struct{}{}
// Launch goroutine that async writes input into single channel
go func(index int) {
defer func() {
// If the input closes we need to signal to the broker
i.inputClosedChan <- index
}()
for {
in, open := <-inputs[index].TransactionChan()
if !open {
return
}
i.transactions <- in
}
}(n)
}
go i.loop()
return i, nil
}
//------------------------------------------------------------------------------
// TransactionChan returns the channel used for consuming transactions from this
// broker.
func (i *FanIn) TransactionChan() <-chan types.Transaction {
return i.transactions
}
//------------------------------------------------------------------------------
// loop is an internal loop that brokers incoming messages to many outputs.
func (i *FanIn) loop() {
defer func() {
close(i.inputClosedChan)
close(i.transactions)
close(i.closedChan)
}()
for len(i.inputMap) > 0 {
index := <-i.inputClosedChan
delete(i.inputMap, index)
}
}
// CloseAsync shuts down the FanIn broker and stops processing requests.
func (i *FanIn) CloseAsync() {
for _, closable := range i.closables {
closable.CloseAsync()
}
}
// WaitForClose blocks until the FanIn broker has closed down.
func (i *FanIn) WaitForClose(timeout time.Duration) error {
select {
case <-i.closedChan:
case <-time.After(timeout):
return types.ErrTimeout
}
return nil
}
//------------------------------------------------------------------------------