Examples with Headers io.undertow.util.Headers used on opensource projects

Example 1 with Headers

use of io.undertow.util.Headers in project divolte-collector by divolte.

the class JavaScriptHandler method handleRequest.

@Override
public void handleRequest(final HttpServerExchange exchange) throws Exception {
    if (logger.isDebugEnabled()) {
        logger.debug("Requested received for {} from {}", resource.getResourceName(), exchange.getSourceAddress().getHostString());
    }
    // Start with headers that we always set the same way.
    final HeaderMap responseHeaders = exchange.getResponseHeaders();
    responseHeaders.put(Headers.CACHE_CONTROL, CACHE_CONTROL_HEADER_VALUE);
    // Figure out if we possibly need to deal with a compressed response,
    // based on client capability.
    final GzippableHttpBody uncompressedBody = resource.getEntityBody();
    final Optional<HttpBody> gzippedBody = uncompressedBody.getGzippedBody();
    final HttpBody bodyToSend;
    if (gzippedBody.isPresent()) {
        /*
             * Compressed responses can use Content-Encoding and/or Transfer-Encoding.
             * The semantics differ slightly, but it is suffice to say that most user
             * agents don't advertise their Transfer-Encoding support.
             * So for now we only support the Content-Encoding mechanism.
             * Some other notes:
             *  - Some clients implement 'deflate' incorrectly. Hence we only support 'gzip',
             *    despite it having slightly more overhead.
             *  - We don't use Undertow's built-in compression support because we've
             *    pre-calculated the compressed response and expect to serve it up
             *    repeatedly, instead of calculating it on-the-fly for every request.
             */
        responseHeaders.put(Headers.VARY, Headers.ACCEPT_ENCODING_STRING);
        final HeaderValues acceptEncoding = exchange.getRequestHeaders().get(Headers.ACCEPT_ENCODING);
        if (null != acceptEncoding && acceptEncoding.stream().anyMatch((header) -> Iterables.contains(HEADER_SPLITTER.split(header), "gzip"))) {
            responseHeaders.put(Headers.CONTENT_ENCODING, "gzip");
            bodyToSend = gzippedBody.get();
        } else {
            bodyToSend = uncompressedBody;
        }
    } else {
        bodyToSend = uncompressedBody;
    }
    // Now we know which version of the entity is visible to this user-agent,
    // figure out if the client already has the current version or not.
    final ETag eTag = bodyToSend.getETag();
    responseHeaders.put(Headers.ETAG, eTag.toString());
    if (ETagUtils.handleIfNoneMatch(exchange, eTag, true)) {
        final ByteBuffer entityBody = bodyToSend.getBody();
        responseHeaders.put(Headers.CONTENT_TYPE, "application/javascript");
        exchange.getResponseSender().send(entityBody);
    } else {
        exchange.setStatusCode(StatusCodes.NOT_MODIFIED);
        exchange.endExchange();
    }
}