1 package de.halbekunst.juplo.cachecontrol;
3 import java.io.ByteArrayOutputStream;
4 import java.io.IOException;
5 import java.io.OutputStream;
6 import java.io.PrintWriter;
7 import java.text.ParseException;
8 import java.text.SimpleDateFormat;
9 import java.util.Collections;
10 import java.util.Enumeration;
11 import java.util.HashMap;
12 import java.util.Locale;
14 import java.util.zip.GZIPOutputStream;
15 import javax.servlet.Filter;
16 import javax.servlet.FilterChain;
17 import javax.servlet.FilterConfig;
18 import javax.servlet.ServletException;
19 import javax.servlet.ServletOutputStream;
20 import javax.servlet.ServletRequest;
21 import javax.servlet.ServletResponse;
22 import javax.servlet.http.HttpServletRequest;
23 import javax.servlet.http.HttpServletResponse;
24 import javax.servlet.http.HttpServletResponseWrapper;
25 import org.slf4j.Logger;
26 import org.slf4j.LoggerFactory;
27 import org.springframework.beans.factory.annotation.Autowire;
28 import org.springframework.beans.factory.annotation.Autowired;
29 import org.springframework.beans.factory.annotation.Configurable;
37 @Configurable(autowire=Autowire.BY_NAME)
38 public class AcceleratorFilter implements Filter {
39 private final static Logger log = LoggerFactory.getLogger(AcceleratorFilter.class);
41 private final static Map<String,String> EMPTY = Collections.unmodifiableMap(new HashMap<String,String>());
43 public final static String REQUEST_URI_ATTRIBUTE = "javax.servlet.include.request_uri";
44 public final static String RESPONSE_WRAPPER = AcceleratorFilter.class.getName() + ".RESPONSE_WRAPPER";
47 @Autowired CacheControl cacheControl;
48 @Autowired(required=true) Integer buffer;
49 @Autowired(required=true) String eTag;
50 @Autowired(required=true) Boolean weak;
51 @Autowired(required=true) Long lastModified;
52 @Autowired(required=true) Integer cacheSeconds;
56 public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
57 if (!(request instanceof HttpServletRequest)) {
58 log.error("AcceleratorFilter can only handle HTTP-requests");
59 chain.doFilter(request, response);
63 /** Prüfen, ob es sich um eine Anfrage für einen JSP-Include handelt */
64 if (request.getAttribute(REQUEST_URI_ATTRIBUTE) != null) {
65 log.debug("Includes cannot be accelerated");
66 chain.doFilter(request, response);
70 HttpServletRequest httpRequest = (HttpServletRequest)request;
71 HttpServletResponse httpResponse = (HttpServletResponse)response;
72 AccelerationWrapper wrapper = new AccelerationWrapper(httpRequest, httpResponse);
73 httpRequest.setAttribute(RESPONSE_WRAPPER, wrapper);
74 cacheControl.init(wrapper);
75 chain.doFilter(request, wrapper);
80 public void init(FilterConfig filterConfig) throws ServletException {
84 public void destroy() {
88 class AccelerationWrapper extends HttpServletResponseWrapper implements CacheMethodHandle {
90 private final HttpServletRequest request;
91 private final HttpServletResponse response;
93 boolean zipped; // CacheControll greift direkt auf dieses Flag zu!
94 boolean forceCompression = false;
96 private CountingServletOutputStream out;
97 private ServletOutputStream stream;
98 private PrintWriter writer;
100 private boolean guessing = true;
104 private int cacheSeconds;
105 private boolean cacheSecondsSet = false;
106 private long lastModified, expires = 0l;
108 private boolean weak;
109 private Map<String,String> cacheParams;
112 AccelerationWrapper(HttpServletRequest request, HttpServletResponse response) throws IOException {
115 this.request = request;
116 this.response = response;
118 now = System.currentTimeMillis();
119 status = HttpServletResponse.SC_OK;
120 cacheSeconds = AcceleratorFilter.this.cacheSeconds;
121 lastModified = AcceleratorFilter.this.lastModified;
122 eTag = AcceleratorFilter.this.eTag;
123 weak = AcceleratorFilter.this.weak;
124 cacheParams = new HashMap<String,String>();
127 Enumeration values = request.getHeaders(Headers.HEADER_ACCEPT_ENCODING);
128 while (values.hasMoreElements()) {
129 String value = (String) values.nextElement();
130 if (value.indexOf("gzip") != -1) {
136 out = new GZIPServletOutputStream();
138 out = new CountingServletOutputStream();
141 public void finish() throws IOException {
147 public void setStatus(int sc) {
148 response.setStatus(sc);
151 cacheControl.decorate(request, response, this);
153 catch (Exception e) {
154 log.error("Error while decorating response", e);
159 public void setStatus(int sc, String sm) {
160 response.setStatus(sc,sm);
163 cacheControl.decorate(request, response, this);
165 catch (Exception e) {
166 log.error("Error while decorating response", e);
171 public void addDateHeader(String name, long value) {
174 super.addDateHeader(name, value);
178 if (Headers.HEADER_DATE.equalsIgnoreCase(name)) {
180 calculateCacheSeconds();
184 if (Headers.HEADER_EXPIRES.equalsIgnoreCase(name)) {
186 calculateCacheSeconds();
190 if (Headers.HEADER_LAST_MODIFIED.equalsIgnoreCase(name)) {
191 lastModified = value;
195 /** Unknown header: pass throug! */
196 super.addDateHeader(name, value);
200 public void addHeader(String name, String value) {
203 super.addHeader(name, value);
209 analyzeHeader(name, value, false);
213 public void addIntHeader(String name, int value) {
216 super.addIntHeader(name, value);
220 analyzeHeader(name, Integer.toString(value), false);
224 public void setDateHeader(String name, long value) {
227 super.setDateHeader(name, value);
231 if (Headers.HEADER_DATE.equalsIgnoreCase(name)) {
233 calculateCacheSeconds();
237 if (Headers.HEADER_EXPIRES.equalsIgnoreCase(name)) {
239 calculateCacheSeconds();
243 if (Headers.HEADER_LAST_MODIFIED.equalsIgnoreCase(name)) {
244 lastModified = value;
248 /** Unknown header: pass throug! */
249 super.setDateHeader(name, value);
253 public void setHeader(String name, String value) {
256 super.setHeader(name, value);
260 analyzeHeader(name, value, true);
264 public void setIntHeader(String name, int value) {
267 super.setIntHeader(name, value);
271 analyzeHeader(name, Integer.toString(value), true);
275 public ServletOutputStream getOutputStream() throws IOException {
278 throw new IllegalStateException("ServletOutputStream and PrintWriter cannot be requested both!");
280 if (stream == null) {
288 public PrintWriter getWriter() throws IOException {
291 throw new IllegalStateException("ServletOutputStream and PrintWriter cannot be requested both!");
293 if (writer == null) {
294 writer = new PrintWriter(out);
301 public void setContentLength(int len) {
303 log.info("Supressing explicit content-length {} for request {}, because content will be zipped!", len, request.getRequestURI());
305 response.setContentLength(len);
309 public void setBufferSize(int size) {
312 response.setBufferSize(size);
316 public void flushBuffer() throws IOException {
318 forceCompression = true;
319 cacheControl.decorate(request, response, this);
320 response.flushBuffer();
324 public void resetBuffer() {
326 response.resetBuffer();
329 out = new GZIPServletOutputStream();
331 out = new CountingServletOutputStream();
333 catch (IOException e) {
334 throw new IllegalStateException(e);
341 public void reset() {
346 out = new GZIPServletOutputStream();
348 out = new CountingServletOutputStream();
350 catch (IOException e) {
351 throw new IllegalStateException(e);
356 /** Cookies has been cleared! Reinitialize decorator... */
357 forceCompression = false;
358 cacheControl.init(this);
364 public boolean isZipped() {
365 return out.isZipped();
369 public long getTimestamp() {
374 public int accepts(HttpServletRequest request) {
379 public int getCacheSeconds(HttpServletRequest request) {
384 public long getLastModified(HttpServletRequest request) {
389 public String getETag(HttpServletRequest request) {
394 public boolean isETagWeak() {
399 public void cacheControl(HttpServletRequest request, Map<String, String> cacheControlMap) {
400 cacheControlMap.putAll(cacheParams);
404 public Map<String,String> getAdditionalHeaders(HttpServletRequest request) {
408 public void supressGuessing() {
413 private void analyzeHeader(String name, String value, boolean overwrite) {
418 if (name.equalsIgnoreCase(Headers.HEADER_DATE)) {
421 now = System.currentTimeMillis();
422 cacheSeconds = AcceleratorFilter.this.cacheSeconds;
427 SimpleDateFormat parser = new SimpleDateFormat(Headers.RFC_1123_DATE_FORMAT, Locale.US);
428 now = parser.parse(value).getTime();
429 calculateCacheSeconds();
431 catch (ParseException e) {
432 log.warn("ignoring date for header \"Date\" in invalid format: {}", value);
437 if (name.equalsIgnoreCase(Headers.HEADER_EXPIRES)) {
441 cacheSeconds = AcceleratorFilter.this.cacheSeconds;
446 SimpleDateFormat parser = new SimpleDateFormat(Headers.RFC_1123_DATE_FORMAT, Locale.US);
447 expires = parser.parse(value).getTime();
448 calculateCacheSeconds();
450 catch (ParseException e) {
451 log.warn("ignoring date for header \"Expires\" in invalid format: {}", value);
456 if (name.equalsIgnoreCase(Headers.HEADER_LAST_MODIFIED)) {
459 lastModified = AcceleratorFilter.this.lastModified;
463 SimpleDateFormat parser = new SimpleDateFormat(Headers.RFC_1123_DATE_FORMAT, Locale.US);
464 lastModified = parser.parse(value).getTime();
466 catch (ParseException e) {
467 log.warn("ignoring date for header \"Last-Modified\" in invalid format: {}", value);
472 if (name.equalsIgnoreCase(Headers.HEADER_ETAG)) {
475 eTag = AcceleratorFilter.this.eTag;
476 weak = AcceleratorFilter.this.weak;
480 value = value.trim();
482 int end = value.length();
483 if (value.startsWith("W/")) {
490 if (value.charAt(start) == '"')
493 log.warn("Quote at the beginning ov ETag is missing: {}", value);
494 if (value.charAt(end -1) == '"')
497 log.warn("Quote at the end of ETag is missing: {}", value);
498 eTag = value.substring(start, end);
499 String filtered = eTag.replaceAll("[^\\x00-\\x21\\x23-\\x7F]+","");
500 if (filtered.length() < eTag.length()) {
501 log.warn("filtering out illegal characters in ETag: \"{}\" -> \"{}\"", eTag, filtered);
506 if (name.equalsIgnoreCase(Headers.HEADER_CACHE_CONTROL)) {
511 for (String param : value.split(",")) {
512 param = param.trim();
513 int pos = param.indexOf("=");
515 cacheParams.put(param, null);
518 String paramName = param.substring(0, pos).trim();
519 if (paramName.equalsIgnoreCase("max-age")) {
521 cacheSeconds = Integer.parseInt(param.substring(pos + 1));
522 cacheSecondsSet = true;
524 catch (NumberFormatException e) {
525 log.warn("illegal value for Header \"Cache-Control\":", param);
529 cacheParams.put(paramName, param.substring(pos + 1));
536 if (name.equalsIgnoreCase(Headers.HEADER_PRAGMA)) {
537 if (value != null && value.trim().equalsIgnoreCase("no-cache"))
542 /** Pass header through, if no value from intrest was found */
544 super.setHeader(name, value);
546 super.addHeader(name, value);
549 private void calculateCacheSeconds() {
550 if (!cacheSecondsSet && expires >= now) {
551 cacheSeconds = (int)(expires/1000 - now/1000);
552 log.debug("calculating cache-seconds from DATE and EXPIRES: {}", cacheSeconds);
557 class CountingServletOutputStream extends ServletOutputStream {
559 private OutputStream out;
564 CountingServletOutputStream() throws IOException {
565 out = response.getOutputStream();
571 void setBuffer(int size) throws IllegalStateException {}
577 void finish() throws IOException {
581 void decorate() throws IOException {
583 AcceleratorFilter.this.cacheControl.decorate(AccelerationWrapper.this.request, response, AccelerationWrapper.this);
585 catch (Exception e) {
586 log.error("Error while guessing Cache-Header's", e);
587 response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
593 public void close() throws IOException {
599 public void flush() throws IOException {
605 public void write(int i) throws IOException {
615 final class GZIPServletOutputStream extends CountingServletOutputStream {
617 final static int MINIMAL_BUFFER_SIZE = 128;
619 private ByteArrayOutputStream buffer;
620 private OutputStream out;
621 private GZIPOutputStream zout;
622 private int bufferSize;
623 private boolean decorated = false;
626 public GZIPServletOutputStream() throws IOException {
627 setBuffer(AcceleratorFilter.this.buffer);
632 void finish() throws IOException {
635 super.out.write(buffer.toByteArray());
646 void setBuffer(int size) throws IllegalStateException {
648 throw new IllegalStateException("attemp to change buffer size after writing data to response!");
650 if (size > MINIMAL_BUFFER_SIZE) {
654 out = response.getOutputStream();
655 buffer = new ByteArrayOutputStream(size);
656 zout = new GZIPOutputStream(buffer, size);
659 catch (IOException e) {
660 throw new IllegalStateException(e);
668 public void close() throws IOException {
671 out.write(buffer.toByteArray());
676 public void flush() throws IOException {
678 out.write(buffer.toByteArray());
683 public void write(int i) throws IOException {
690 out.write(buffer.toByteArray());