ceph-csi/vendor/google.golang.org/grpc/resolver/manual/manual.go

113 lines
3.5 KiB
Go
Raw Normal View History

/*
*
* Copyright 2017 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 manual defines a resolver that can be used to manually send resolved
// addresses to ClientConn.
package manual
import (
"sync"
"google.golang.org/grpc/resolver"
)
// NewBuilderWithScheme creates a new test resolver builder with the given scheme.
func NewBuilderWithScheme(scheme string) *Resolver {
return &Resolver{
BuildCallback: func(resolver.Target, resolver.ClientConn, resolver.BuildOptions) {},
UpdateStateCallback: func(error) {},
ResolveNowCallback: func(resolver.ResolveNowOptions) {},
CloseCallback: func() {},
scheme: scheme,
}
}
// Resolver is also a resolver builder.
// It's build() function always returns itself.
type Resolver struct {
// BuildCallback is called when the Build method is called. Must not be
// nil. Must not be changed after the resolver may be built.
BuildCallback func(resolver.Target, resolver.ClientConn, resolver.BuildOptions)
// UpdateStateCallback is called when the UpdateState method is called on
// the resolver. The value passed as argument to this callback is the value
// returned by the resolver.ClientConn. Must not be nil. Must not be
// changed after the resolver may be built.
UpdateStateCallback func(err error)
// ResolveNowCallback is called when the ResolveNow method is called on the
// resolver. Must not be nil. Must not be changed after the resolver may
// be built.
ResolveNowCallback func(resolver.ResolveNowOptions)
// CloseCallback is called when the Close method is called. Must not be
// nil. Must not be changed after the resolver may be built.
CloseCallback func()
scheme string
// Fields actually belong to the resolver.
mu sync.Mutex // Guards access to CC.
CC resolver.ClientConn
bootstrapState *resolver.State
}
// InitialState adds initial state to the resolver so that UpdateState doesn't
// need to be explicitly called after Dial.
func (r *Resolver) InitialState(s resolver.State) {
r.bootstrapState = &s
}
// Build returns itself for Resolver, because it's both a builder and a resolver.
func (r *Resolver) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOptions) (resolver.Resolver, error) {
r.mu.Lock()
r.CC = cc
r.mu.Unlock()
r.BuildCallback(target, cc, opts)
if r.bootstrapState != nil {
r.UpdateState(*r.bootstrapState)
}
return r, nil
}
// Scheme returns the test scheme.
func (r *Resolver) Scheme() string {
return r.scheme
}
// ResolveNow is a noop for Resolver.
func (r *Resolver) ResolveNow(o resolver.ResolveNowOptions) {
r.ResolveNowCallback(o)
}
// Close is a noop for Resolver.
func (r *Resolver) Close() {
r.CloseCallback()
}
// UpdateState calls CC.UpdateState.
func (r *Resolver) UpdateState(s resolver.State) {
r.mu.Lock()
err := r.CC.UpdateState(s)
r.mu.Unlock()
r.UpdateStateCallback(err)
}
// ReportError calls CC.ReportError.
func (r *Resolver) ReportError(err error) {
r.mu.Lock()
r.CC.ReportError(err)
r.mu.Unlock()
}