}
}

type adsStream interface {
	Send(*discovery.DiscoveryResponse) error
	Recv() (*discovery.DiscoveryRequest, error)
	Context() context.Context
}

// StreamAggregatedResources is an implementation of XDS API used for proxying between Istiod and Envoy.
// Every time envoy makes a fresh connection to the agent, we reestablish a new connection to the upstream xds

	pre = append(pre, authzBuilder.BuildHTTP(cls)...)
	// TODO: these feel like the wrong place to insert, but this retains backwards compatibility with the original implementation
	post = extension.PopAppendHTTP(post, wasm, extensions.PluginPhase_STATS)
	post = extension.PopAppendHTTP(post, wasm, extensions.PluginPhase_UNSPECIFIED_PHASE)
	post = append(post, xdsfilters.WaypointUpstreamMetadataFilter)

// etc). The Proxy is initialized when a sidecar connects to Pilot, and populated from
// 'node' info in the protocol as well as data extracted from registries.
//
// In current Istio implementation nodes use a 4-parts '~' delimited ID.
// Type~IPAddress~ID~Domain
type Proxy struct {
	sync.RWMutex

	// Type specifies the node type. First part of the ID.
	Type NodeType

func (v *PeerCertVerifier) AddMappings(certMap map[string][]*x509.Certificate) {
	for trustDomain, certs := range certMap {
		v.AddMapping(trustDomain, certs)
	}
}

// VerifyPeerCert is an implementation of tls.Config.VerifyPeerCertificate.
// It verifies the peer certificate using the root certificates associated with its trust domain.
func (v *PeerCertVerifier) VerifyPeerCert(rawCerts [][]byte, _ [][]*x509.Certificate) error {

	debounceMax time.Duration

	// enableEDSDebounce indicates whether EDS pushes should be debounced.
	enableEDSDebounce bool
}

// DiscoveryServer is Pilot's gRPC implementation for Envoy's xds APIs
type DiscoveryServer struct {
	// Env is the model environment.
	Env *model.Environment

	// Generators allow customizing the generated config, based on the client metadata.

type EndpointShards struct {
	// mutex protecting below map.
	sync.RWMutex

	// Shards is used to track the shards. EDS updates are grouped by shard.
	// Current implementation uses the registry name as key - in multicluster this is the
	// name of the k8s cluster, derived from the config (secret).
	Shards map[ShardKey][]*IstioEndpoint

// All SniDnat clusters are internal services in the mesh.
// TODO enable cache - there is no blockers here, skipped to simplify the original caching implementation
func (configgen *ConfigGeneratorImpl) buildOutboundSniDnatClusters(proxy *model.Proxy, req *model.PushRequest,
	cp clusterPatcher,
) []*cluster.Cluster {
	clusters := make([]*cluster.Cluster, 0)

		filters = append(filters, lb.authzBuilder.BuildHTTP(httpOpts.class)...)
		// TODO: these feel like the wrong place to insert, but this retains backwards compatibility with the original implementation
		filters = extension.PopAppendHTTP(filters, wasm, extensions.PluginPhase_STATS)
		filters = extension.PopAppendHTTP(filters, wasm, extensions.PluginPhase_UNSPECIFIED_PHASE)
	}

// 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 crdclient provides an implementation of the config store and cache
// using Kubernetes Custom Resources and the informer framework from Kubernetes
//
// This code relies heavily on code generation for performance reasons; to implement the

		}
	}
	return nil
}

// Follow the 8 step Sieve as in
// https://www.envoyproxy.io/docs/envoy/latest/api-v3/config/listener/v3/listener_components.proto.html#config-listener-v3-filterchainmatch
// The implementation may initially be confusing because of a property of the
// Envoy algorithm - at each level we will filter out all FilterChains that do
// not match. This means an empty match (`{}`) may not match if another chain