grpc-go/xds/internal/client/client_watchers_rds.go

48 lines
1.4 KiB
Go

/*
*
* Copyright 2020 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 client
import (
"fmt"
"time"
)
type rdsUpdate struct {
clusterName string
}
type rdsCallbackFunc func(rdsUpdate, error)
// watchRDS starts a listener watcher for the service..
//
// Note that during race (e.g. an xDS response is received while the user is
// calling cancel()), there's a small window where the callback can be called
// after the watcher is canceled. The caller needs to handle this case.
func (c *Client) watchRDS(routeName string, cb rdsCallbackFunc) (cancel func()) {
wi := &watchInfo{
typeURL: rdsURL,
target: routeName,
rdsCallback: cb,
}
wi.expiryTimer = time.AfterFunc(defaultWatchExpiryTimeout, func() {
c.scheduleCallback(wi, rdsUpdate{}, fmt.Errorf("xds: RDS target %s not found, watcher timeout", routeName))
})
return c.watch(wi)
}