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
|
/*
*
* Copyright 2018 gRPC authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License 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 service manages connections between the VM application and the ALTS
// handshaker service.
package service
import (
"sync"
grpc "google.golang.org/grpc"
"google.golang.org/grpc/credentials/insecure"
)
var (
// mu guards hsConnMap and hsDialer.
mu sync.Mutex
// hsConn represents a mapping from a hypervisor handshaker service address
// to a corresponding connection to a hypervisor handshaker service
// instance.
hsConnMap = make(map[string]*grpc.ClientConn)
// hsDialer will be reassigned in tests.
hsDialer = grpc.Dial
)
// Dial dials the handshake service in the hypervisor. If a connection has
// already been established, this function returns it. Otherwise, a new
// connection is created.
func Dial(hsAddress string) (*grpc.ClientConn, error) {
mu.Lock()
defer mu.Unlock()
hsConn, ok := hsConnMap[hsAddress]
if !ok {
// Create a new connection to the handshaker service. Note that
// this connection stays open until the application is closed.
var err error
hsConn, err = hsDialer(hsAddress, grpc.WithTransportCredentials(insecure.NewCredentials()))
if err != nil {
return nil, err
}
hsConnMap[hsAddress] = hsConn
}
return hsConn, nil
}
// CloseForTesting closes all open connections to the handshaker service.
//
// For testing purposes only.
func CloseForTesting() error {
for _, hsConn := range hsConnMap {
if hsConn == nil {
continue
}
if err := hsConn.Close(); err != nil {
return err
}
}
// Reset the connection map.
hsConnMap = make(map[string]*grpc.ClientConn)
return nil
}
|
