private static HandlerCollection createHandlers()

in gateway-server/src/main/java/org/apache/knox/gateway/GatewayServer.java [465:547]
55 lines of code
6 McCabe index (conditional complexity)

  private static HandlerCollection createHandlers(
      final GatewayConfig config,
      final GatewayServices services,
      final ContextHandlerCollection contexts,
      final Map<String, Integer> topologyPortMap) {

    final Map<String, Handler> contextToHandlerMap = new HashMap<>();
    if(contexts.getHandlers() != null) {
      Arrays.asList(contexts.getHandlers()).stream()
          .filter(h -> h instanceof WebAppContext)
          .forEach(h -> contextToHandlerMap
              .put(((WebAppContext) h).getContextPath(), h));
    }

    HandlerCollection handlers = new HandlerCollection();
    RequestLogHandler logHandler = new RequestLogHandler();

    logHandler.setRequestLog( new AccessHandler() );

    TraceHandler traceHandler = new TraceHandler();
    traceHandler.setHandler( contexts );
    traceHandler.setTracedBodyFilter( System.getProperty( "org.apache.knox.gateway.trace.body.status.filter" ) );

    CorrelationHandler correlationHandler = new CorrelationHandler();
    correlationHandler.setHandler( traceHandler );

    // Used to correct the {target} part of request with Topology Port Mapping feature
    final PortMappingHelperHandler portMappingHandler = new PortMappingHelperHandler(config);
    portMappingHandler.setHandler(correlationHandler);

     // If topology to port mapping feature is enabled then we add new Handler {RequestForwardHandler}
     // to the chain, this handler listens on the configured port (in gateway-site.xml)
     // and simply forwards requests to the correct context path.

     //  The reason for adding ContextHandler is so that we can add a connector
     // to it on which the handler listens (exclusively).


    if (config.isGatewayPortMappingEnabled()) {

      /* Do the virtual host bindings for all the defined topology port mapped
      *  contexts except for the one that has gateway port to prevent issues
      *  with context deployment */
      topologyPortMap
          .entrySet()
          .stream()
          .filter(e -> !e.getValue().equals(config.getGatewayPort()))
          .forEach( entry ->  {
            log.createJettyHandler(entry.getKey());
            final Handler context = contextToHandlerMap
                .get("/" + config.getGatewayPath() + "/" + entry.getKey());

            if(context !=  null) {
              ((WebAppContext) context).setVirtualHosts(
                  new String[] { "@" + entry.getKey().toLowerCase(Locale.ROOT) });
            } else {
              // no topology found for mapping entry.getKey()
              log.noMappedTopologyFound(entry.getKey());
            }
          });
    }

    handlers.addHandler(logHandler);

    if(config.isStrictTransportEnabled()) {
      final String strictTransportOption = config.getStrictTransportOption();
      handlers.addHandler(new HSTSHandler(strictTransportOption));
      log.strictTransportHeaderEnabled(strictTransportOption);
    }

    if (config.isWebsocketEnabled()) {
      final GatewayWebsocketHandler websocketHandler = new GatewayWebsocketHandler(
          config, services);
      websocketHandler.setHandler(portMappingHandler);

      handlers.addHandler(websocketHandler);

    } else {
      handlers.addHandler(portMappingHandler);
    }

    return handlers;
  }