diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/resolver_conn_wrapper.go')
-rw-r--r-- | vendor/google.golang.org/grpc/resolver_conn_wrapper.go | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go new file mode 100644 index 0000000..50991ea --- /dev/null +++ b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go | |||
@@ -0,0 +1,155 @@ | |||
1 | /* | ||
2 | * | ||
3 | * Copyright 2017 gRPC authors. | ||
4 | * | ||
5 | * Licensed under the Apache License, Version 2.0 (the "License"); | ||
6 | * you may not use this file except in compliance with the License. | ||
7 | * You may obtain a copy of the License at | ||
8 | * | ||
9 | * http://www.apache.org/licenses/LICENSE-2.0 | ||
10 | * | ||
11 | * Unless required by applicable law or agreed to in writing, software | ||
12 | * distributed under the License is distributed on an "AS IS" BASIS, | ||
13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
14 | * See the License for the specific language governing permissions and | ||
15 | * limitations under the License. | ||
16 | * | ||
17 | */ | ||
18 | |||
19 | package grpc | ||
20 | |||
21 | import ( | ||
22 | "fmt" | ||
23 | "strings" | ||
24 | |||
25 | "google.golang.org/grpc/grpclog" | ||
26 | "google.golang.org/grpc/internal/channelz" | ||
27 | "google.golang.org/grpc/resolver" | ||
28 | ) | ||
29 | |||
30 | // ccResolverWrapper is a wrapper on top of cc for resolvers. | ||
31 | // It implements resolver.ClientConnection interface. | ||
32 | type ccResolverWrapper struct { | ||
33 | cc *ClientConn | ||
34 | resolver resolver.Resolver | ||
35 | addrCh chan []resolver.Address | ||
36 | scCh chan string | ||
37 | done chan struct{} | ||
38 | lastAddressesCount int | ||
39 | } | ||
40 | |||
41 | // split2 returns the values from strings.SplitN(s, sep, 2). | ||
42 | // If sep is not found, it returns ("", "", false) instead. | ||
43 | func split2(s, sep string) (string, string, bool) { | ||
44 | spl := strings.SplitN(s, sep, 2) | ||
45 | if len(spl) < 2 { | ||
46 | return "", "", false | ||
47 | } | ||
48 | return spl[0], spl[1], true | ||
49 | } | ||
50 | |||
51 | // parseTarget splits target into a struct containing scheme, authority and | ||
52 | // endpoint. | ||
53 | // | ||
54 | // If target is not a valid scheme://authority/endpoint, it returns {Endpoint: | ||
55 | // target}. | ||
56 | func parseTarget(target string) (ret resolver.Target) { | ||
57 | var ok bool | ||
58 | ret.Scheme, ret.Endpoint, ok = split2(target, "://") | ||
59 | if !ok { | ||
60 | return resolver.Target{Endpoint: target} | ||
61 | } | ||
62 | ret.Authority, ret.Endpoint, ok = split2(ret.Endpoint, "/") | ||
63 | if !ok { | ||
64 | return resolver.Target{Endpoint: target} | ||
65 | } | ||
66 | return ret | ||
67 | } | ||
68 | |||
69 | // newCCResolverWrapper parses cc.target for scheme and gets the resolver | ||
70 | // builder for this scheme and builds the resolver. The monitoring goroutine | ||
71 | // for it is not started yet and can be created by calling start(). | ||
72 | // | ||
73 | // If withResolverBuilder dial option is set, the specified resolver will be | ||
74 | // used instead. | ||
75 | func newCCResolverWrapper(cc *ClientConn) (*ccResolverWrapper, error) { | ||
76 | rb := cc.dopts.resolverBuilder | ||
77 | if rb == nil { | ||
78 | return nil, fmt.Errorf("could not get resolver for scheme: %q", cc.parsedTarget.Scheme) | ||
79 | } | ||
80 | |||
81 | ccr := &ccResolverWrapper{ | ||
82 | cc: cc, | ||
83 | addrCh: make(chan []resolver.Address, 1), | ||
84 | scCh: make(chan string, 1), | ||
85 | done: make(chan struct{}), | ||
86 | } | ||
87 | |||
88 | var err error | ||
89 | ccr.resolver, err = rb.Build(cc.parsedTarget, ccr, resolver.BuildOption{DisableServiceConfig: cc.dopts.disableServiceConfig}) | ||
90 | if err != nil { | ||
91 | return nil, err | ||
92 | } | ||
93 | return ccr, nil | ||
94 | } | ||
95 | |||
96 | func (ccr *ccResolverWrapper) resolveNow(o resolver.ResolveNowOption) { | ||
97 | ccr.resolver.ResolveNow(o) | ||
98 | } | ||
99 | |||
100 | func (ccr *ccResolverWrapper) close() { | ||
101 | ccr.resolver.Close() | ||
102 | close(ccr.done) | ||
103 | } | ||
104 | |||
105 | // NewAddress is called by the resolver implemenetion to send addresses to gRPC. | ||
106 | func (ccr *ccResolverWrapper) NewAddress(addrs []resolver.Address) { | ||
107 | select { | ||
108 | case <-ccr.done: | ||
109 | return | ||
110 | default: | ||
111 | } | ||
112 | grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs) | ||
113 | if channelz.IsOn() { | ||
114 | ccr.addChannelzTraceEvent(addrs) | ||
115 | } | ||
116 | ccr.cc.handleResolvedAddrs(addrs, nil) | ||
117 | } | ||
118 | |||
119 | // NewServiceConfig is called by the resolver implemenetion to send service | ||
120 | // configs to gRPC. | ||
121 | func (ccr *ccResolverWrapper) NewServiceConfig(sc string) { | ||
122 | select { | ||
123 | case <-ccr.done: | ||
124 | return | ||
125 | default: | ||
126 | } | ||
127 | grpclog.Infof("ccResolverWrapper: got new service config: %v", sc) | ||
128 | ccr.cc.handleServiceConfig(sc) | ||
129 | } | ||
130 | |||
131 | func (ccr *ccResolverWrapper) addChannelzTraceEvent(addrs []resolver.Address) { | ||
132 | if len(addrs) == 0 && ccr.lastAddressesCount != 0 { | ||
133 | channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{ | ||
134 | Desc: "Resolver returns an empty address list", | ||
135 | Severity: channelz.CtWarning, | ||
136 | }) | ||
137 | } else if len(addrs) != 0 && ccr.lastAddressesCount == 0 { | ||
138 | var s string | ||
139 | for i, a := range addrs { | ||
140 | if a.ServerName != "" { | ||
141 | s += a.Addr + "(" + a.ServerName + ")" | ||
142 | } else { | ||
143 | s += a.Addr | ||
144 | } | ||
145 | if i != len(addrs)-1 { | ||
146 | s += " " | ||
147 | } | ||
148 | } | ||
149 | channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{ | ||
150 | Desc: fmt.Sprintf("Resolver returns a non-empty address list (previous one was empty) %q", s), | ||
151 | Severity: channelz.CtINFO, | ||
152 | }) | ||
153 | } | ||
154 | ccr.lastAddressesCount = len(addrs) | ||
155 | } | ||