google.golang.org/grpc@v1.74.2/xds/internal/internal.go (about)

     1  /*
     2   *
     3   * Copyright 2019 gRPC authors.
     4   *
     5   * Licensed under the Apache License, Version 2.0 (the "License");
     6   * you may not use this file except in compliance with the License.
     7   * You may obtain a copy of the License at
     8   *
     9   *     http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   */
    17  
    18  // Package internal contains functions/structs shared by xds
    19  // balancers/resolvers.
    20  package internal
    21  
    22  import (
    23  	"fmt"
    24  
    25  	"google.golang.org/grpc/resolver"
    26  	"google.golang.org/grpc/xds/internal/clients"
    27  )
    28  
    29  // LocalityString generates a string representation of clients.Locality in the
    30  // format specified in gRFC A76.
    31  func LocalityString(l clients.Locality) string {
    32  	return fmt.Sprintf("{region=%q, zone=%q, sub_zone=%q}", l.Region, l.Zone, l.SubZone)
    33  }
    34  
    35  // IsLocalityEqual allows the values to be compared by Attributes.Equal.
    36  func IsLocalityEqual(l clients.Locality, o any) bool {
    37  	ol, ok := o.(clients.Locality)
    38  	if !ok {
    39  		return false
    40  	}
    41  	return l.Region == ol.Region && l.Zone == ol.Zone && l.SubZone == ol.SubZone
    42  }
    43  
    44  // LocalityFromString converts a string representation of clients.locality as
    45  // specified in gRFC A76, into a LocalityID struct.
    46  func LocalityFromString(s string) (ret clients.Locality, _ error) {
    47  	_, err := fmt.Sscanf(s, "{region=%q, zone=%q, sub_zone=%q}", &ret.Region, &ret.Zone, &ret.SubZone)
    48  	if err != nil {
    49  		return clients.Locality{}, fmt.Errorf("%s is not a well formatted locality ID, error: %v", s, err)
    50  	}
    51  	return ret, nil
    52  }
    53  
    54  type localityKeyType string
    55  
    56  const localityKey = localityKeyType("grpc.xds.internal.address.locality")
    57  
    58  // GetLocalityID returns the locality ID of addr.
    59  func GetLocalityID(addr resolver.Address) clients.Locality {
    60  	path, _ := addr.BalancerAttributes.Value(localityKey).(clients.Locality)
    61  	return path
    62  }
    63  
    64  // SetLocalityID sets locality ID in addr to l.
    65  func SetLocalityID(addr resolver.Address, l clients.Locality) resolver.Address {
    66  	addr.BalancerAttributes = addr.BalancerAttributes.WithValue(localityKey, l)
    67  	return addr
    68  }
    69  
    70  // SetLocalityIDInEndpoint sets locality ID in endpoint to l.
    71  func SetLocalityIDInEndpoint(endpoint resolver.Endpoint, l clients.Locality) resolver.Endpoint {
    72  	endpoint.Attributes = endpoint.Attributes.WithValue(localityKey, l)
    73  	return endpoint
    74  }
    75  
    76  // ResourceTypeMapForTesting maps TypeUrl to corresponding ResourceType.
    77  var ResourceTypeMapForTesting map[string]any
    78  
    79  // UnknownCSMLabels are TelemetryLabels emitted from CDS if CSM Telemetry Label
    80  // data is not present in the CDS Resource.
    81  var UnknownCSMLabels = map[string]string{
    82  	"csm.service_name":           "unknown",
    83  	"csm.service_namespace_name": "unknown",
    84  }