-
Notifications
You must be signed in to change notification settings - Fork 4.4k
/
clientimpl_authority.go
141 lines (131 loc) · 4.65 KB
/
clientimpl_authority.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
138
139
140
141
/*
*
* Copyright 2022 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 xdsclient
import (
"errors"
"fmt"
"google.golang.org/grpc/internal/grpclog"
"google.golang.org/grpc/internal/xds/bootstrap"
"google.golang.org/grpc/xds/internal/xdsclient/xdsresource"
)
// findAuthority returns the authority for this name. If it doesn't already
// exist, one will be created.
//
// Note that this doesn't always create new authority. authorities with the same
// config but different names are shared.
//
// The returned unref function must be called when the caller is done using this
// authority, without holding c.authorityMu.
//
// Caller must not hold c.authorityMu.
func (c *clientImpl) findAuthority(n *xdsresource.Name) (*authority, func(), error) {
scheme, authority := n.Scheme, n.Authority
c.authorityMu.Lock()
defer c.authorityMu.Unlock()
if c.done.HasFired() {
return nil, nil, errors.New("the xds-client is closed")
}
config := c.config.XDSServer
if scheme == xdsresource.FederationScheme {
cfg, ok := c.config.Authorities[authority]
if !ok {
return nil, nil, fmt.Errorf("xds: failed to find authority %q", authority)
}
if cfg.XDSServer != nil {
config = cfg.XDSServer
}
}
a, err := c.newAuthorityLocked(config)
if err != nil {
return nil, nil, fmt.Errorf("xds: failed to connect to the control plane for authority %q: %v", authority, err)
}
// All returned authority from this function will be used by a watch,
// holding the ref here.
//
// Note that this must be done while c.authorityMu is held, to avoid the
// race that an authority is returned, but before the watch starts, the
// old last watch is canceled (in another goroutine), causing this
// authority to be removed, and then a watch will start on a removed
// authority.
//
// unref() will be done when the watch is canceled.
a.refLocked()
return a, func() { c.unrefAuthority(a) }, nil
}
// newAuthorityLocked creates a new authority for the given config. If an
// authority for the given config exists in the cache, it is returned instead of
// creating a new one.
//
// The caller must take a reference of the returned authority before using, and
// unref afterwards.
//
// caller must hold c.authorityMu
func (c *clientImpl) newAuthorityLocked(config *bootstrap.ServerConfig) (_ *authority, retErr error) {
// First check if there's already an authority for this config. If found, it
// means this authority is used by other watches (could be the same
// authority name, or a different authority name but the same server
// config). Return it.
configStr := config.String()
if a, ok := c.authorities[configStr]; ok {
return a, nil
}
// Second check if there's an authority in the idle cache. If found, it
// means this authority was created, but moved to the idle cache because the
// watch was canceled. Move it from idle cache to the authority cache, and
// return.
if old, ok := c.idleAuthorities.Remove(configStr); ok {
oldA, _ := old.(*authority)
if oldA != nil {
c.authorities[configStr] = oldA
return oldA, nil
}
}
// Make a new authority since there's no existing authority for this config.
ret, err := newAuthority(authorityArgs{
serverCfg: config,
bootstrapCfg: c.config,
serializer: c.serializer,
resourceTypeGetter: c.resourceTypes.get,
watchExpiryTimeout: c.watchExpiryTimeout,
logger: grpclog.NewPrefixLogger(logger, authorityPrefix(c, config.ServerURI)),
})
if err != nil {
return nil, fmt.Errorf("creating new authority for config %q: %v", config.String(), err)
}
// Add it to the cache, so it will be reused.
c.authorities[configStr] = ret
return ret, nil
}
// unrefAuthority unrefs the authority. It also moves the authority to idle
// cache if it's ref count is 0.
//
// This function doesn't need to called explicitly. It's called by the returned
// unref from findAuthority().
//
// Caller must not hold c.authorityMu.
func (c *clientImpl) unrefAuthority(a *authority) {
c.authorityMu.Lock()
defer c.authorityMu.Unlock()
if a.unrefLocked() > 0 {
return
}
configStr := a.serverCfg.String()
delete(c.authorities, configStr)
c.idleAuthorities.Add(configStr, a, func() {
a.close()
})
}