private HttpResponse buildHttpResponse()

in zuul-core/src/main/java/com/netflix/zuul/netty/server/ClientResponseWriter.java [172:213]
30 lines of code
8 McCabe index (conditional complexity)

    private HttpResponse buildHttpResponse(HttpResponseMessage zuulResp) {
        HttpRequestInfo zuulRequest = zuulResp.getInboundRequest();
        HttpVersion responseHttpVersion;
        String inboundProtocol = zuulRequest.getProtocol();
        if (inboundProtocol.startsWith("HTTP/1")) {
            responseHttpVersion = HttpVersion.valueOf(inboundProtocol);
        } else {
            // Default to 1.1. We do this to cope with HTTP/2 inbound requests.
            responseHttpVersion = HttpVersion.HTTP_1_1;
        }

        // Create the main http response to send, with body.
        DefaultHttpResponse nativeResponse = new DefaultHttpResponse(
                responseHttpVersion, HttpResponseStatus.valueOf(zuulResp.getStatus()), false, false);

        // Now set all of the response headers - note this is a multi-set in keeping with HTTP semantics
        HttpHeaders nativeHeaders = nativeResponse.headers();
        for (Header entry : zuulResp.getHeaders().entries()) {
            nativeHeaders.add(entry.getKey(), entry.getValue());
        }

        // Netty does not automatically add Content-Length or Transfer-Encoding: chunked. So we add here if missing.
        if (!HttpUtil.isContentLengthSet(nativeResponse) && !HttpUtil.isTransferEncodingChunked(nativeResponse)) {
            nativeResponse.headers().add(HttpHeaderNames.TRANSFER_ENCODING, HttpHeaderValues.CHUNKED);
        }

        HttpRequest nativeReq = (HttpRequest) zuulResp.getContext().get(CommonContextKeys.NETTY_HTTP_REQUEST);
        if (!closeConnection && HttpUtil.isKeepAlive(nativeReq)) {
            HttpUtil.setKeepAlive(nativeResponse, true);
        } else {
            // Send a Connection: close response header (only needed for HTTP/1.0 but no harm in doing for 1.1 too).
            nativeResponse.headers().set("Connection", "close");
        }

        // TODO - temp hack for http/2 handling.
        if (nativeReq.headers().contains(HttpConversionUtil.ExtensionHeaderNames.STREAM_ID.text())) {
            String streamId = nativeReq.headers().get(HttpConversionUtil.ExtensionHeaderNames.STREAM_ID.text());
            nativeResponse.headers().set(HttpConversionUtil.ExtensionHeaderNames.STREAM_ID.text(), streamId);
        }

        return nativeResponse;
    }