istio.io/istio@v0.0.0-20240520182934-d79c90f27776/pilot/pkg/networking/core/name_table.go (about)

     1  // Copyright Istio Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package core
    16  
    17  import (
    18  	"istio.io/istio/pilot/pkg/features"
    19  	"istio.io/istio/pilot/pkg/model"
    20  	dnsProto "istio.io/istio/pkg/dns/proto"
    21  	dnsServer "istio.io/istio/pkg/dns/server"
    22  )
    23  
    24  // BuildNameTable produces a table of hostnames and their associated IPs that can then
    25  // be used by the agent to resolve DNS. This logic is always active. However, local DNS resolution
    26  // will only be effective if DNS capture is enabled in the proxy
    27  func (configgen *ConfigGeneratorImpl) BuildNameTable(node *model.Proxy, push *model.PushContext) *dnsProto.NameTable {
    28  	if node.Type != model.SidecarProxy {
    29  		// DNS resolution is only for sidecars
    30  		return nil
    31  	}
    32  	return dnsServer.BuildNameTable(dnsServer.Config{
    33  		Node:                        node,
    34  		Push:                        push,
    35  		MulticlusterHeadlessEnabled: features.MulticlusterHeadlessEnabled,
    36  	})
    37  }