path:
                        - key: payload
                        - key: iss
                        value:
                          stringMatch:
                            exact: requestPrincipals
                    - metadata:
                        filter: envoy.filters.http.jwt_authn
                        path:
                        - key: payload
                        - key: sub

public class ChannelMessage extends InterHubMessage implements Routable {
    private final ChannelIdentifier channel;
    private final Object payload;

    public ChannelMessage(ChannelIdentifier channel, Object payload) {
        this.channel = channel;
        this.payload = payload;
    }

    @Override
    public Delivery getDelivery() {
        return Delivery.SingleHandler;
    }

    @Override

  /** Send a ping with the supplied [payload]. */
  @Throws(IOException::class)
  fun writePing(payload: ByteString) {
    writeControlFrame(OPCODE_CONTROL_PING, payload)
  }

  /** Send a pong with the supplied [payload]. */
  @Throws(IOException::class)
  fun writePong(payload: ByteString) {
    writeControlFrame(OPCODE_CONTROL_PONG, payload)
  }

  /**

	b.Cleanup(grid.Cleanup)
	// Create n managers.
	for _, remote := range grid.Managers {
		// Register a single handler which echos the payload.
		errFatal(remote.RegisterSingleHandler(handlerTest, func(payload []byte) ([]byte, *RemoteErr) {
			defer PutByteBuffer(payload)
			return append(GetByteBuffer()[:0], payload...), nil
		}))
		errFatal(rpc.Register(remote, func(req *testRequest) (resp *testResponse, err *RemoteErr) {
			return &testResponse{

	var sub *subHandlerID
	if m.Payload == nil {
		m.Payload = GetByteBuffer()[:0]
	}
	h, err := m.UnmarshalMsg(b)
	if err != nil {
		return nil, nil, fmt.Errorf("read write: %v", err)
	}
	if len(m.Payload) == 0 && m.Flags&FlagPayloadIsZero == 0 {
		PutByteBuffer(m.Payload)
		m.Payload = nil
	}
	if m.Flags&FlagCRCxxh3 != 0 {
		const hashLen = 4

        then:
        received1.class.classLoader == received2.class.classLoader
        received1.payload.class.classLoader == received2.payload.class.classLoader
        reply1.class == wrapperClass
        reply1.payload.class == payloadClass
        reply2.class == wrapperClass
        reply2.payload.class == payloadClass
    }

    void assertNotVisible(Class<?> from, Class<?> to) {
        try {

                        - key: payload
                        - key: iss
                        value:
                          stringMatch:
                            exact: rule[0]-from[0]-requestPrincipal[1]
                    - metadata:
                        filter: envoy.filters.http.jwt_authn
                        path:
                        - key: payload
                        - key: sub

 */
public class BuildEvent extends Message {
    private final Object payload;

    public BuildEvent(Object payload) {
        this.payload = payload;
    }

    public Object getPayload() {
        return payload;
    }

    @Override
    public String toString() {
        return getClass().getSimpleName() + "[event=" + payload + "]";
    }

  }

  fun assertTextMessage(payload: String?) {
    assertThat(nextEvent()).isEqualTo(Message(string = payload))
  }

  fun assertBinaryMessage(payload: ByteString?) {
    assertThat(nextEvent()).isEqualTo(Message(payload))
  }

  fun assertPing(payload: ByteString) {
    assertThat(nextEvent()).isEqualTo(Ping(payload))
  }

  fun assertPong(payload: ByteString) {

    now = int(time.time())
    payload = {
        # expire in one hour.
        "exp": now + 3600,
        "iat": now,
    }
    if args.iss:
        payload["iss"] = args.iss

    if args.sub:
        payload["sub"] = args.sub
    else:
        payload["sub"] = args.iss

    if args.aud:
        if "," in args.aud:
            payload["aud"] = args.aud.split(",")
        else: