func LocalRequestHandler()

in proxy/protocol/http/sidecar.go [108:174]
60 lines of code
10 McCabe index (conditional complexity)

func LocalRequestHandler(w http.ResponseWriter, r *http.Request) {
	prepareRequest(r)
	inv := consumerPreHandler(r)
	remoteIP := stringutil.SplitFirstSep(r.RemoteAddr, ":")

	var err error
	h := make(map[string]string)
	for k := range r.Header {
		h[k] = r.Header.Get(k)
	}
	//Resolve Destination
	destination, port, err := dr.Resolve(remoteIP, r.Host, r.URL.String(), h)
	if err != nil {
		handleErrorResponse(inv, w, http.StatusBadRequest, err)
		return
	}
	inv.MicroServiceName = destination
	if port != "" {
		h[XForwardedPort] = port
	}

	//transfer header into ctx
	inv.Ctx = context.WithValue(inv.Ctx, chassisCommon.ContextHeaderKey{}, h)

	var c *handler.Chain
	ok, egressRule := egress.Match(inv.MicroServiceName)
	if ok {
		var targetPort int32 = 80
		for _, port := range egressRule.Ports {
			if strings.EqualFold(port.Protocol, common.HTTPProtocol) {
				targetPort = port.Port
				break
			}
		}
		inv.Endpoint = inv.MicroServiceName + ":" + strconv.Itoa(int(targetPort))
		c, err = handler.GetChain(common.ConsumerEgress, common.ChainConsumerEgress)
		if err != nil {
			handleErrorResponse(inv, w, http.StatusBadGateway, err)
			openlog.Error("Get chain failed" + err.Error())
			return
		}

	} else {
		c, err = handler.GetChain(chassisCommon.Consumer, common.ChainConsumerOutgoing)
		if err != nil {
			handleErrorResponse(inv, w, http.StatusBadGateway, err)
			openlog.Error("Get chain failed: " + err.Error())
			return
		}
	}
	defer func(begin time.Time) {
		timeTaken := time.Since(begin).Seconds()
		serviceLabelValues := map[string]string{metrics.LServiceName: inv.MicroServiceName, metrics.LApp: inv.RouteTags.AppID(), metrics.LVersion: inv.RouteTags.Version()}
		metrics.RecordLatency(serviceLabelValues, timeTaken)
	}(time.Now())
	var invRsp *invocation.Response
	c.Next(inv, func(ir *invocation.Response) {
		//Send the request to the destination
		invRsp = ir
	})
	resp, err := handleRequest(w, inv, invRsp)
	if err != nil {
		openlog.Error("handle request failed: " + err.Error())
		return
	}
	RecordStatus(inv, resp.StatusCode)
}