VictoriaMetrics/vendor/google.golang.org/grpc/xds/internal/internal.go
2021-11-08 12:39:57 +02:00

83 lines
2.4 KiB
Go

/*
*
* Copyright 2019 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 internal contains functions/structs shared by xds
// balancers/resolvers.
package internal
import (
"encoding/json"
"fmt"
"google.golang.org/grpc/resolver"
)
// LocalityID is xds.Locality without XXX fields, so it can be used as map
// keys.
//
// xds.Locality cannot be map keys because one of the XXX fields is a slice.
type LocalityID struct {
Region string `json:"region,omitempty"`
Zone string `json:"zone,omitempty"`
SubZone string `json:"subZone,omitempty"`
}
// ToString generates a string representation of LocalityID by marshalling it into
// json. Not calling it String() so printf won't call it.
func (l LocalityID) ToString() (string, error) {
b, err := json.Marshal(l)
if err != nil {
return "", err
}
return string(b), nil
}
// Equal allows the values to be compared by Attributes.Equal.
func (l LocalityID) Equal(o interface{}) bool {
ol, ok := o.(LocalityID)
if !ok {
return false
}
return l.Region == ol.Region && l.Zone == ol.Zone && l.SubZone == ol.SubZone
}
// LocalityIDFromString converts a json representation of locality, into a
// LocalityID struct.
func LocalityIDFromString(s string) (ret LocalityID, _ error) {
err := json.Unmarshal([]byte(s), &ret)
if err != nil {
return LocalityID{}, fmt.Errorf("%s is not a well formatted locality ID, error: %v", s, err)
}
return ret, nil
}
type localityKeyType string
const localityKey = localityKeyType("grpc.xds.internal.address.locality")
// GetLocalityID returns the locality ID of addr.
func GetLocalityID(addr resolver.Address) LocalityID {
path, _ := addr.BalancerAttributes.Value(localityKey).(LocalityID)
return path
}
// SetLocalityID sets locality ID in addr to l.
func SetLocalityID(addr resolver.Address, l LocalityID) resolver.Address {
addr.BalancerAttributes = addr.BalancerAttributes.WithValue(localityKey, l)
return addr
}