aboutsummaryrefslogtreecommitdiffhomepage
path: root/vendor/google.golang.org/api/internal/pool.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/google.golang.org/api/internal/pool.go')
-rw-r--r--vendor/google.golang.org/api/internal/pool.go61
1 files changed, 61 insertions, 0 deletions
diff --git a/vendor/google.golang.org/api/internal/pool.go b/vendor/google.golang.org/api/internal/pool.go
new file mode 100644
index 0000000..ba40624
--- /dev/null
+++ b/vendor/google.golang.org/api/internal/pool.go
@@ -0,0 +1,61 @@
1// Copyright 2016 Google LLC
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package internal
16
17import (
18 "errors"
19
20 "google.golang.org/grpc/naming"
21)
22
23// PoolResolver provides a fixed list of addresses to load balance between
24// and does not provide further updates.
25type PoolResolver struct {
26 poolSize int
27 dialOpt *DialSettings
28 ch chan []*naming.Update
29}
30
31// NewPoolResolver returns a PoolResolver
32// This is an EXPERIMENTAL API and may be changed or removed in the future.
33func NewPoolResolver(size int, o *DialSettings) *PoolResolver {
34 return &PoolResolver{poolSize: size, dialOpt: o}
35}
36
37// Resolve returns a Watcher for the endpoint defined by the DialSettings
38// provided to NewPoolResolver.
39func (r *PoolResolver) Resolve(target string) (naming.Watcher, error) {
40 if r.dialOpt.Endpoint == "" {
41 return nil, errors.New("No endpoint configured")
42 }
43 addrs := make([]*naming.Update, 0, r.poolSize)
44 for i := 0; i < r.poolSize; i++ {
45 addrs = append(addrs, &naming.Update{Op: naming.Add, Addr: r.dialOpt.Endpoint, Metadata: i})
46 }
47 r.ch = make(chan []*naming.Update, 1)
48 r.ch <- addrs
49 return r, nil
50}
51
52// Next returns a static list of updates on the first call,
53// and blocks indefinitely until Close is called on subsequent calls.
54func (r *PoolResolver) Next() ([]*naming.Update, error) {
55 return <-r.ch, nil
56}
57
58// Close releases resources associated with the pool and causes Next to unblock.
59func (r *PoolResolver) Close() {
60 close(r.ch)
61}