// matches only a single label. You cannot have a wildcard label by itself (e.g. Host == "*").
  // Requests will be matched against the Host field in the following way:
  // 1. If Host is precise, the request matches this rule if the http host header is equal to Host.
  // 2. If Host is a wildcard, then the request matches this rule if the http host header
  // is to equal to the suffix (removing the first label) of the wildcard rule.

        requestBuilder.removeHeader("Transfer-Encoding")
        requestBuilder.removeHeader("Content-Length")
        requestBuilder.removeHeader("Content-Type")
      }
    }

    // When redirecting across hosts, drop all authentication headers. This
    // is potentially annoying to the application layer since they have no
    // way to retain them.
    if (!userResponse.request.url.canReuseConnectionFor(url)) {

Next, for an individual proxy we will check if it could possibly be impacted by the change. For example, we know a sidecar never is impacted by a `Gateway` update, and we can also look at scoping (from `Sidecar.egress.hosts`) to further restrict update scopes.

import okio.Buffer
import okio.BufferedSink
import okio.BufferedSource
import okio.ByteString
import okio.buffer
import okio.sink
import okio.source

/**
 * A socket connection to a remote peer. A connection hosts streams which can send and receive
 * data.
 *
 * Many methods in this API are **synchronous:** the call is completed before the method returns.

  // (`scheme://host:port/path`). Exactly one of `url` or `service`
  // must be specified.
  //
  // The `host` should not refer to a service running in the cluster; use
  // the `service` field instead. The host might be resolved via external
  // DNS in some apiservers (e.g., `kube-apiserver` cannot resolve
  // in-cluster DNS as that would be a layering violation). `host` may
  // also be an IP address.
  //

  // (`scheme://host:port/path`). Exactly one of `url` or `service`
  // must be specified.
  //
  // The `host` should not refer to a service running in the cluster; use
  // the `service` field instead. The host might be resolved via external
  // DNS in some apiservers (e.g., `kube-apiserver` cannot resolve
  // in-cluster DNS as that would be a layering violation). `host` may
  // also be an IP address.
  //

          )
      }

    /**
     * @param host either a regular hostname, International Domain Name, IPv4 address, or IPv6
     * address.
     */
    fun host(host: String) =
      apply {
        val encoded =
          host.percentDecode().toCanonicalHost()
            ?: throw IllegalArgumentException("unexpected host: $host")
        this.host = encoded
      }

    fun port(port: Int) =

 *  Fix: Don’t allow remote peer to arbitrarily size the HPACK decoder dynamic
    table.
 *  Fix: Honor per-host configuration in Android’s network security config.
    Previously disabling cleartext for any host would disable cleartext for all
    hosts. Note that this setting is only available on Android 24+.
 *  New: HPACK compression is now dynamic. This should improve performance when

# Typically same as GOPATH/bin, so tests work seamlessly with IDEs.

export ISTIO_BIN=$(GOBIN)

# If we are running in the Linux build container on non Linux hosts, we add the
# linux binaries to the build dependencies, BUILD_DEPS, which can be added to other targets
# that would need the Linux binaries (ex. tests).
BUILD_DEPS:=
ifeq ($(IN_BUILD_CONTAINER),1)

// pod's hosts file.
message HostAlias {
  // IP address of the host file entry.
  optional string ip = 1;

  // Hostnames for the above IP address.
  repeated string hostnames = 2;
}

// Represents a host path mapped into a pod.
// Host path volumes do not support ownership management or SELinux relabeling.