Java Code Examples for io.undertow.util.ETagUtils#handleIfNoneMatch()

/**
 * Serve static resource for the directory listing
 *
 * @param exchange The exchange
 * @return true if resources were served
 */
public static boolean sendRequestedBlobs(HttpServerExchange exchange) {
    ByteBuf buffer = null;
    String type = null;
    String etag = null;
    String quotedEtag = null;
    if ("css".equals(exchange.getQueryString())) {
        buffer = Blobs.FILE_CSS_BUFFER.duplicate();
        type = "text/css";
        etag = Blobs.FILE_CSS_ETAG;
        quotedEtag = Blobs.FILE_CSS_ETAG_QUOTED;
    } else if ("js".equals(exchange.getQueryString())) {
        buffer = Blobs.FILE_JS_BUFFER.duplicate();
        type = "application/javascript";
        etag = Blobs.FILE_JS_ETAG;
        quotedEtag = Blobs.FILE_JS_ETAG_QUOTED;
    }

    if (buffer != null) {

        if (!ETagUtils.handleIfNoneMatch(exchange, new ETag(false, etag), false)) {
            exchange.setStatusCode(StatusCodes.NOT_MODIFIED);
            return true;
        }

        exchange.setResponseHeader(HttpHeaderNames.CONTENT_LENGTH, String.valueOf(buffer.readableBytes()));
        exchange.setResponseHeader(HttpHeaderNames.CONTENT_TYPE, type);
        exchange.setResponseHeader(HttpHeaderNames.ETAG, quotedEtag);
        if (HttpMethodNames.HEAD.equals(exchange.getRequestMethod())) {
            exchange.endExchange();
            return true;
        }
        exchange.writeAsync(buffer.duplicate(), true, IoCallback.END_EXCHANGE, null);

        return true;
    }

    return false;
}
 

/**
 * Serve static resource for the directory listing
 *
 * @param exchange The exchange
 * @return true if resources were served
 */
public static boolean sendRequestedBlobs(HttpServerExchange exchange) {
    ByteBuffer buffer = null;
    String type = null;
    String etag = null;
    String quotedEtag = null;
    if ("css".equals(exchange.getQueryString())) {
        buffer = Blobs.FILE_CSS_BUFFER.duplicate();
        type = "text/css";
        etag = Blobs.FILE_CSS_ETAG;
        quotedEtag = Blobs.FILE_CSS_ETAG_QUOTED;
    } else if ("js".equals(exchange.getQueryString())) {
        buffer = Blobs.FILE_JS_BUFFER.duplicate();
        type = "application/javascript";
        etag = Blobs.FILE_JS_ETAG;
        quotedEtag = Blobs.FILE_JS_ETAG_QUOTED;
    }

    if (buffer != null) {

        if(!ETagUtils.handleIfNoneMatch(exchange, new ETag(false, etag), false)) {
            exchange.setStatusCode(StatusCodes.NOT_MODIFIED);
            return true;
        }

        exchange.getResponseHeaders().put(Headers.CONTENT_LENGTH, String.valueOf(buffer.limit()));
        exchange.getResponseHeaders().put(Headers.CONTENT_TYPE, type);
        exchange.getResponseHeaders().put(Headers.ETAG, quotedEtag);
        if (Methods.HEAD.equals(exchange.getRequestMethod())) {
            exchange.endExchange();
            return true;
        }
        exchange.getResponseSender().send(buffer);

        return true;
    }

    return false;
}
 

@Override
public void handleRequest(final HttpServerExchange exchange) {
    final InetSocketAddress sourceAddress = captureAndPersistSourceAddress(exchange);

    /*
     * Set up the headers that we always send as a response, irrespective of what type it
     * will be. Note that the client is responsible for ensuring that ensures that each request
     * is unique.
     * The cache-related headers are intended to prevent spurious reloads for an event.
     * (Being a GET request, agents are free to re-issue the request at will. We don't want this.)
     * As a last resort, we try to detect duplicates via the ETag header.
     */
    exchange.getResponseHeaders()
            .put(Headers.CONTENT_TYPE, "image/gif")
            .put(Headers.ETAG, SENTINEL_ETAG_VALUE)
            .put(Headers.CACHE_CONTROL, "private, no-cache, proxy-revalidate")
            .put(Headers.PRAGMA, "no-cache")
            .put(Headers.EXPIRES, "Fri, 14 Apr 1995 11:30:00 GMT");

    // If an ETag is present, this is a duplicate event.
    if (ETagUtils.handleIfNoneMatch(exchange, SENTINEL_ETAG, true)) {
        // Default status code what we want: 200 OK.
        // Sending the response before logging the event!
        exchange.getResponseSender().send(transparentImage.slice());

        try {
            logEvent(exchange);
        } catch (final IncompleteRequestException ire) {
            // improper request, could be anything
            logger.debug("Improper request received from {}.", Optional.ofNullable(exchange.getSourceAddress()).map(InetSocketAddress::getHostString).orElse("<UNKNOWN HOST>"));
        }
    } else {
        if (logger.isDebugEnabled()) {
            logger.debug("Ignoring duplicate event from {}: {}", sourceAddress, getFullUrl(exchange));
        }
        exchange.setStatusCode(StatusCodes.NOT_MODIFIED);
        exchange.endExchange();
    }
}
 

private void serveFileBlocking(final HttpServletRequest req, final HttpServletResponse resp, final Resource resource, HttpServerExchange exchange) throws IOException {
    final ETag etag = resource.getETag();
    final Date lastModified = resource.getLastModified();
    if (req.getDispatcherType() != DispatcherType.INCLUDE) {
        if (!ETagUtils.handleIfMatch(req.getHeader(HttpHeaderNames.IF_MATCH), etag, false) ||
                !DateUtils.handleIfUnmodifiedSince(req.getHeader(HttpHeaderNames.IF_UNMODIFIED_SINCE), lastModified)) {
            resp.setStatus(StatusCodes.PRECONDITION_FAILED);
            return;
        }
        if (!ETagUtils.handleIfNoneMatch(req.getHeader(HttpHeaderNames.IF_NONE_MATCH), etag, true) ||
                !DateUtils.handleIfModifiedSince(req.getHeader(HttpHeaderNames.IF_MODIFIED_SINCE), lastModified)) {
            if (req.getMethod().equals(HttpMethodNames.GET) || req.getMethod().equals(HttpMethodNames.HEAD)) {
                resp.setStatus(StatusCodes.NOT_MODIFIED);
            } else {
                resp.setStatus(StatusCodes.PRECONDITION_FAILED);
            }
            return;
        }
    }

    //we are going to proceed. Set the appropriate headers
    if (resp.getContentType() == null) {
        if (!resource.isDirectory()) {
            final String contentType = deployment.getServletContext().getMimeType(resource.getName());
            if (contentType != null) {
                resp.setContentType(contentType);
            } else {
                resp.setContentType("application/octet-stream");
            }
        }
    }
    if (lastModified != null) {
        resp.setHeader(HttpHeaderNames.LAST_MODIFIED, resource.getLastModifiedString());
    }
    if (etag != null) {
        resp.setHeader(HttpHeaderNames.ETAG, etag.toString());
    }
    ByteRange.RangeResponseResult rangeResponse = null;
    long start = -1, end = -1;
    try {
        //only set the content length if we are using a stream
        //if we are using a writer who knows what the length will end up being
        //todo: if someone installs a filter this can cause problems
        //not sure how best to deal with this
        //we also can't deal with range requests if a writer is in use
        Long contentLength = resource.getContentLength();
        if (contentLength != null) {
            resp.getOutputStream();
            if (contentLength > Integer.MAX_VALUE) {
                resp.setContentLengthLong(contentLength);
            } else {
                resp.setContentLength(contentLength.intValue());
            }
            if (resource instanceof RangeAwareResource && ((RangeAwareResource) resource).isRangeSupported() && resource.getContentLength() != null) {
                resp.setHeader(HttpHeaderNames.ACCEPT_RANGES, "bytes");
                //TODO: figure out what to do with the content encoded resource manager
                final ByteRange range = ByteRange.parse(req.getHeader(HttpHeaderNames.RANGE));
                if (range != null) {
                    rangeResponse = range.getResponseResult(resource.getContentLength(), req.getHeader(HttpHeaderNames.IF_RANGE), resource.getLastModified(), resource.getETag() == null ? null : resource.getETag().getTag());
                    if (rangeResponse != null) {
                        start = rangeResponse.getStart();
                        end = rangeResponse.getEnd();
                        resp.setStatus(rangeResponse.getStatusCode());
                        resp.setHeader(HttpHeaderNames.CONTENT_RANGE, rangeResponse.getContentRange());
                        long length = rangeResponse.getContentLength();
                        if (length > Integer.MAX_VALUE) {
                            resp.setContentLengthLong(length);
                        } else {
                            resp.setContentLength((int) length);
                        }
                        if (rangeResponse.getStatusCode() == StatusCodes.REQUEST_RANGE_NOT_SATISFIABLE) {
                            return;
                        }
                    }
                }
            }
        }
    } catch (IllegalStateException e) {

    }
    final boolean include = req.getDispatcherType() == DispatcherType.INCLUDE;
    if (!req.getMethod().equals(HttpMethodNames.HEAD)) {
        if (rangeResponse == null) {
            resource.serveBlocking(exchange.getOutputStream(), exchange);
        } else {
            ((RangeAwareResource) resource).serveRangeBlocking(exchange.getOutputStream(), exchange, start, end);
        }
    }
}
 

private void serveFileBlocking(final HttpServletRequest req, final HttpServletResponse resp, final Resource resource, HttpServerExchange exchange) throws IOException {
    final ETag etag = resource.getETag();
    final Date lastModified = resource.getLastModified();
    if(req.getDispatcherType() != DispatcherType.INCLUDE) {
        if (!ETagUtils.handleIfMatch(req.getHeader(Headers.IF_MATCH_STRING), etag, false) ||
                !DateUtils.handleIfUnmodifiedSince(req.getHeader(Headers.IF_UNMODIFIED_SINCE_STRING), lastModified)) {
            resp.setStatus(StatusCodes.PRECONDITION_FAILED);
            return;
        }
        if (!ETagUtils.handleIfNoneMatch(req.getHeader(Headers.IF_NONE_MATCH_STRING), etag, true) ||
                !DateUtils.handleIfModifiedSince(req.getHeader(Headers.IF_MODIFIED_SINCE_STRING), lastModified)) {
            if(req.getMethod().equals(Methods.GET_STRING) || req.getMethod().equals(Methods.HEAD_STRING)) {
                resp.setStatus(StatusCodes.NOT_MODIFIED);
            } else {
                resp.setStatus(StatusCodes.PRECONDITION_FAILED);
            }
            return;
        }
    }

    //we are going to proceed. Set the appropriate headers
    if(resp.getContentType() == null) {
        if(!resource.isDirectory()) {
            final String contentType = deployment.getServletContext().getMimeType(resource.getName());
            if (contentType != null) {
                resp.setContentType(contentType);
            } else {
                resp.setContentType("application/octet-stream");
            }
        }
    }
    if (lastModified != null) {
        resp.setHeader(Headers.LAST_MODIFIED_STRING, resource.getLastModifiedString());
    }
    if (etag != null) {
        resp.setHeader(Headers.ETAG_STRING, etag.toString());
    }
    ByteRange.RangeResponseResult rangeResponse = null;
    long start = -1, end = -1;
    try {
        //only set the content length if we are using a stream
        //if we are using a writer who knows what the length will end up being
        //todo: if someone installs a filter this can cause problems
        //not sure how best to deal with this
        //we also can't deal with range requests if a writer is in use
        Long contentLength = resource.getContentLength();
        if (contentLength != null) {
            resp.getOutputStream();
            if(contentLength > Integer.MAX_VALUE) {
                resp.setContentLengthLong(contentLength);
            } else {
                resp.setContentLength(contentLength.intValue());
            }
            if(resource instanceof RangeAwareResource && ((RangeAwareResource)resource).isRangeSupported() && resource.getContentLength() != null) {
                resp.setHeader(Headers.ACCEPT_RANGES_STRING, "bytes");
                //TODO: figure out what to do with the content encoded resource manager
                final ByteRange range = ByteRange.parse(req.getHeader(Headers.RANGE_STRING));
                if(range != null) {
                    rangeResponse = range.getResponseResult(resource.getContentLength(), req.getHeader(Headers.IF_RANGE_STRING), resource.getLastModified(), resource.getETag() == null ? null : resource.getETag().getTag());
                    if(rangeResponse != null){
                        start = rangeResponse.getStart();
                        end = rangeResponse.getEnd();
                        resp.setStatus(rangeResponse.getStatusCode());
                        resp.setHeader(Headers.CONTENT_RANGE_STRING, rangeResponse.getContentRange());
                        long length = rangeResponse.getContentLength();
                        if(length > Integer.MAX_VALUE) {
                            resp.setContentLengthLong(length);
                        } else {
                            resp.setContentLength((int) length);
                        }
                        if(rangeResponse.getStatusCode() == StatusCodes.REQUEST_RANGE_NOT_SATISFIABLE) {
                            return;
                        }
                    }
                }
            }
        }
    } catch (IllegalStateException e) {

    }
    final boolean include = req.getDispatcherType() == DispatcherType.INCLUDE;
    if (!req.getMethod().equals(Methods.HEAD_STRING)) {
        if(rangeResponse == null) {
            resource.serve(exchange.getResponseSender(), exchange, completionCallback(include));
        } else {
            ((RangeAwareResource)resource).serveRange(exchange.getResponseSender(), exchange, start, end, completionCallback(include));
        }
    }
}
 

@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();
    }
}