diff options
Diffstat (limited to 'vendor/google.golang.org/api/internal/pool.go')
-rw-r--r-- | vendor/google.golang.org/api/internal/pool.go | 61 |
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 000000000..ba406247f --- /dev/null +++ b/vendor/google.golang.org/api/internal/pool.go @@ -0,0 +1,61 @@ +// Copyright 2016 Google LLC +// +// 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 internal + +import ( + "errors" + + "google.golang.org/grpc/naming" +) + +// PoolResolver provides a fixed list of addresses to load balance between +// and does not provide further updates. +type PoolResolver struct { + poolSize int + dialOpt *DialSettings + ch chan []*naming.Update +} + +// NewPoolResolver returns a PoolResolver +// This is an EXPERIMENTAL API and may be changed or removed in the future. +func NewPoolResolver(size int, o *DialSettings) *PoolResolver { + return &PoolResolver{poolSize: size, dialOpt: o} +} + +// Resolve returns a Watcher for the endpoint defined by the DialSettings +// provided to NewPoolResolver. +func (r *PoolResolver) Resolve(target string) (naming.Watcher, error) { + if r.dialOpt.Endpoint == "" { + return nil, errors.New("No endpoint configured") + } + addrs := make([]*naming.Update, 0, r.poolSize) + for i := 0; i < r.poolSize; i++ { + addrs = append(addrs, &naming.Update{Op: naming.Add, Addr: r.dialOpt.Endpoint, Metadata: i}) + } + r.ch = make(chan []*naming.Update, 1) + r.ch <- addrs + return r, nil +} + +// Next returns a static list of updates on the first call, +// and blocks indefinitely until Close is called on subsequent calls. +func (r *PoolResolver) Next() ([]*naming.Update, error) { + return <-r.ch, nil +} + +// Close releases resources associated with the pool and causes Next to unblock. +func (r *PoolResolver) Close() { + close(r.ch) +} |