ALF-13807: Add range header support to the webDAV servlet

* Extracted range header support from BaseDownloadContentServlet into HttpRangeProcessor
* Altered GetMethod in WebDAV to use HttpRangeProcessor



git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@35614 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261
This commit is contained in:
Matt Ward
2012-04-24 12:15:04 +00:00
parent 79c2a14db5
commit 304f8ff0f9

View File

@@ -19,23 +19,21 @@
package org.alfresco.web.app.servlet; package org.alfresco.web.app.servlet;
import java.io.IOException; import java.io.IOException;
import java.io.InputStream;
import java.net.SocketException; import java.net.SocketException;
import java.text.MessageFormat; import java.text.MessageFormat;
import java.util.ArrayList; import java.util.ArrayList;
import java.util.Collections;
import java.util.Date; import java.util.Date;
import java.util.List; import java.util.List;
import java.util.StringTokenizer; import java.util.StringTokenizer;
import javax.servlet.ServletException; import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpServletResponse;
import org.alfresco.error.AlfrescoRuntimeException; import org.alfresco.error.AlfrescoRuntimeException;
import org.alfresco.model.ContentModel; import org.alfresco.model.ContentModel;
import org.alfresco.repo.content.filestore.FileContentReader; import org.alfresco.repo.content.filestore.FileContentReader;
import org.alfresco.repo.web.util.HttpRangeProcessor;
import org.alfresco.service.ServiceRegistry; import org.alfresco.service.ServiceRegistry;
import org.alfresco.service.cmr.model.FileInfo; import org.alfresco.service.cmr.model.FileInfo;
import org.alfresco.service.cmr.model.FileNotFoundException; import org.alfresco.service.cmr.model.FileNotFoundException;
@@ -72,12 +70,6 @@ public abstract class BaseDownloadContentServlet extends BaseServlet
private static final String POWER_POINT_DOCUMENT_MIMETYPE = "application/vnd.ms-powerpoint"; private static final String POWER_POINT_DOCUMENT_MIMETYPE = "application/vnd.ms-powerpoint";
private static final String POWER_POINT_2007_DOCUMENT_MIMETYPE = "application/vnd.openxmlformats-officedocument.presentationml.presentation"; private static final String POWER_POINT_2007_DOCUMENT_MIMETYPE = "application/vnd.openxmlformats-officedocument.presentationml.presentation";
private static final String MULTIPART_BYTERANGES_BOUNDRY = "<ALF4558907921887235966L>";
private static final String MULTIPART_BYTERANGES_HEADER = "multipart/byteranges; boundary=" + MULTIPART_BYTERANGES_BOUNDRY;
private static final String MULTIPART_BYTERANGES_BOUNDRY_SEP = "--" + MULTIPART_BYTERANGES_BOUNDRY;
private static final String MULTIPART_BYTERANGES_BOUNDRY_END = MULTIPART_BYTERANGES_BOUNDRY_SEP + "--";
private static final String HEADER_CONTENT_TYPE = "Content-Type";
private static final String HEADER_CONTENT_RANGE = "Content-Range"; private static final String HEADER_CONTENT_RANGE = "Content-Range";
private static final String HEADER_CONTENT_LENGTH = "Content-Length"; private static final String HEADER_CONTENT_LENGTH = "Content-Length";
private static final String HEADER_ACCEPT_RANGES = "Accept-Ranges"; private static final String HEADER_ACCEPT_RANGES = "Accept-Ranges";
@@ -88,9 +80,6 @@ public abstract class BaseDownloadContentServlet extends BaseServlet
private static final String HEADER_USER_AGENT = "User-Agent"; private static final String HEADER_USER_AGENT = "User-Agent";
private static final String HEADER_CONTENT_DISPOSITION = "Content-Disposition"; private static final String HEADER_CONTENT_DISPOSITION = "Content-Disposition";
/** size of a multi-part byte range output buffer */
private static final int CHUNKSIZE = 64*1024;
protected static final String MIMETYPE_OCTET_STREAM = "application/octet-stream"; protected static final String MIMETYPE_OCTET_STREAM = "application/octet-stream";
protected static final String MSG_ERROR_CONTENT_MISSING = "error_content_missing"; protected static final String MSG_ERROR_CONTENT_MISSING = "error_content_missing";
@@ -336,7 +325,8 @@ public abstract class BaseDownloadContentServlet extends BaseServlet
// ensure the range header is starts with "bytes=" and process the range(s) // ensure the range header is starts with "bytes=" and process the range(s)
if (range.length() > 6) if (range.length() > 6)
{ {
processedRange = processRange( HttpRangeProcessor rangeProcessor = new HttpRangeProcessor(contentService);
processedRange = rangeProcessor.processRange(
res, reader, range.substring(6), nodeRef, propertyQName, res, reader, range.substring(6), nodeRef, propertyQName,
mimetype, req.getHeader(HEADER_USER_AGENT)); mimetype, req.getHeader(HEADER_USER_AGENT));
} }
@@ -408,439 +398,6 @@ public abstract class BaseDownloadContentServlet extends BaseServlet
res.setHeader(HEADER_CONTENT_DISPOSITION, attachmentValue.toString()); res.setHeader(HEADER_CONTENT_DISPOSITION, attachmentValue.toString());
} }
/**
* Process a range header - handles single and multiple range requests.
*/
private boolean processRange(HttpServletResponse res, ContentReader reader, String range,
NodeRef ref, QName property, String mimetype, String userAgent)
throws IOException
{
// test for multiple byte ranges present in header
if (range.indexOf(',') == -1)
{
return processSingleRange(res, reader, range, mimetype);
}
else
{
return processMultiRange(res, range, ref, property, mimetype, userAgent);
}
}
/**
* Process a single range request.
*
* @param res HttpServletResponse
* @param reader ContentReader to retrieve content
* @param range Range header value
* @param mimetype Content mimetype
*
* @return true if processed range, false otherwise
*/
private boolean processSingleRange(HttpServletResponse res, ContentReader reader, String range, String mimetype)
throws IOException
{
// return the specific set of bytes as requested in the content-range header
/* Examples of byte-content-range-spec values, assuming that the entity contains total of 1234 bytes:
The first 500 bytes:
bytes 0-499/1234
The second 500 bytes:
bytes 500-999/1234
All except for the first 500 bytes:
bytes 500-1233/1234 */
/* 'Range' header example:
bytes=10485760-20971519 */
boolean processedRange = false;
Range r = null;
try
{
r = Range.constructRange(range, mimetype, reader.getSize());
}
catch (IllegalArgumentException err)
{
if (getLogger().isDebugEnabled())
getLogger().debug("Failed to parse range header - returning 416 status code: " + err.getMessage());
res.setStatus(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);
res.setHeader(HEADER_CONTENT_RANGE, "\"*\"");
res.getOutputStream().close();
return true;
}
// set Partial Content status and range headers
res.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT);
res.setContentType(mimetype);
String contentRange = "bytes " + Long.toString(r.start) + "-" + Long.toString(r.end) + "/" + Long.toString(reader.getSize());
res.setHeader(HEADER_CONTENT_RANGE, contentRange);
res.setHeader(HEADER_CONTENT_LENGTH, Long.toString((r.end - r.start) + 1L));
if (getLogger().isDebugEnabled())
getLogger().debug("Processing: Content-Range: " + contentRange);
InputStream is = null;
try
{
// output the binary data for the range
ServletOutputStream os = res.getOutputStream();
is = reader.getContentInputStream();
streamRangeBytes(r, is, os, 0L);
os.close();
processedRange = true;
}
catch (IOException err)
{
if (getLogger().isDebugEnabled())
getLogger().debug("Unable to process single range due to IO Exception: " + err.getMessage());
throw err;
}
finally
{
if (is != null) is.close();
}
return processedRange;
}
/**
* Process multiple ranges.
*
* @param res HttpServletResponse
* @param range Range header value
* @param ref NodeRef to the content for streaming
* @param property Content Property for the content
* @param mimetype Mimetype of the content
* @param userAgent User Agent of the caller
*
* @return true if processed range, false otherwise
*/
private boolean processMultiRange(
HttpServletResponse res, String range, NodeRef ref, QName property, String mimetype, String userAgent)
throws IOException
{
final Log logger = getLogger();
// return the sets of bytes as requested in the content-range header
// the response will be formatted as multipart/byteranges media type message
/* Examples of byte-ranges-specifier values (assuming an entity-body of length 10000):
- The first 500 bytes (byte offsets 0-499, inclusive): bytes=0-499
- The second 500 bytes (byte offsets 500-999, inclusive):
bytes=500-999
- The final 500 bytes (byte offsets 9500-9999, inclusive):
bytes=-500
- Or bytes=9500-
- The first and last bytes only (bytes 0 and 9999): bytes=0-0,-1
- Several legal but not canonical specifications of byte offsets 500-999, inclusive:
bytes=500-600,601-999
bytes=500-700,601-999 */
boolean processedRange = false;
// get the content reader
ContentService contentService = getServiceRegistry(getServletContext()).getContentService();
ContentReader reader = contentService.getReader(ref, property);
final List<Range> ranges = new ArrayList<Range>(8);
long entityLength = reader.getSize();
for (StringTokenizer t=new StringTokenizer(range, ", "); t.hasMoreTokens(); /**/)
{
try
{
ranges.add(Range.constructRange(t.nextToken(), mimetype, entityLength));
}
catch (IllegalArgumentException err)
{
if (getLogger().isDebugEnabled())
getLogger().debug("Failed to parse range header - returning 416 status code: " + err.getMessage());
res.setStatus(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);
res.setHeader(HEADER_CONTENT_RANGE, "\"*\"");
res.getOutputStream().close();
return true;
}
}
if (ranges.size() != 0)
{
// merge byte ranges if possible - IE handles this well, FireFox not so much
if (userAgent == null || userAgent.indexOf("MSIE ") != -1)
{
Collections.sort(ranges);
for (int i=0; i<ranges.size() - 1; i++)
{
Range first = ranges.get(i);
Range second = ranges.get(i + 1);
if (first.end + 1 >= second.start)
{
if (logger.isDebugEnabled())
logger.debug("Merging byte range: " + first + " with " + second);
if (first.end < second.end)
{
// merge second range into first
first.end = second.end;
}
// else we simply discard the second range - it is contained within the first
// delete second range
ranges.remove(i + 1);
// reset loop index
i--;
}
}
}
// calculate response content length
long length = MULTIPART_BYTERANGES_BOUNDRY_END.length() + 2;
for (Range r : ranges)
{
length += r.getLength();
}
// output headers as we have at least one range to process
res.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT);
res.setHeader(HEADER_CONTENT_TYPE, MULTIPART_BYTERANGES_HEADER);
res.setHeader(HEADER_CONTENT_LENGTH, Long.toString(length));
ServletOutputStream os = res.getOutputStream();
InputStream is = null;
try
{
for (Range r : ranges)
{
if (logger.isDebugEnabled())
logger.debug("Processing: " + r.getContentRange());
try
{
// output the header bytes for the range
r.outputHeader(os);
// output the binary data for the range
// need a new reader for each new InputStream
is = contentService.getReader(ref, property).getContentInputStream();
streamRangeBytes(r, is, os, 0L);
is.close();
is = null;
// section marker and flush stream
os.println();
os.flush();
}
catch (IOException err)
{
if (getLogger().isDebugEnabled())
getLogger().debug("Unable to process multiple range due to IO Exception: " + err.getMessage());
throw err;
}
}
}
finally
{
if (is != null)
{
is.close();
}
}
// end marker
os.println(MULTIPART_BYTERANGES_BOUNDRY_END);
os.close();
processedRange = true;
}
return processedRange;
}
/**
* Stream a range of bytes from the given InputStream to the ServletOutputStream
*
* @param r Byte Range to process
* @param is InputStream
* @param os ServletOutputStream
* @param offset Assumed InputStream position - to calculate skip bytes from
*
* @return current InputStream position - so the stream can be reused if required
*/
private void streamRangeBytes(final Range r, final InputStream is, final ServletOutputStream os, long offset)
throws IOException
{
final Log logger = getLogger();
final boolean trace = logger.isTraceEnabled();
// TODO: investigate using getFileChannel() on ContentReader
if (r.start != 0L && r.start > offset)
{
long skipped = offset + is.skip(r.start - offset);
if (skipped < r.start)
{
// Nothing left to download!
return;
}
}
long span = (r.end - r.start) + 1L;
long bytesLeft = span;
int read = 0;
byte[] buf = new byte[((int)bytesLeft) < CHUNKSIZE ? (int)bytesLeft : CHUNKSIZE];
while ((read = is.read(buf)) > 0 && bytesLeft != 0L)
{
os.write(buf, 0, read);
bytesLeft -= (long)read;
if (bytesLeft != 0L)
{
int resize = ((int)bytesLeft) < CHUNKSIZE ? (int)bytesLeft : CHUNKSIZE;
if (resize != buf.length)
{
buf = new byte[resize];
}
}
if (trace) logger.trace("...wrote " + read + " bytes, with " + bytesLeft + " to go...");
}
}
/**
* Representation of a single byte range.
*/
private static class Range implements Comparable<Range>
{
private long start;
private long end;
private long entityLength;
private String contentType;
private String contentRange;
/**
* Constructor
*
* @param contentType Mimetype of the range content
* @param start Start position in the parent entity
* @param end End position in the parent entity
* @param entityLength Length of the parent entity
*/
Range(String contentType, long start, long end, long entityLength)
{
this.contentType = HEADER_CONTENT_TYPE + ": " + contentType;
this.start = start;
this.end = end;
this.entityLength = entityLength;
}
/**
* Factory method to construct a byte range from a range header value.
*
* @param range Range header value
* @param contentType Mimetype of the range
* @param entityLength Length of the parent entity
*
* @return Range
*
* @throws IllegalArgumentException for an invalid range
*/
static Range constructRange(String range, String contentType, long entityLength)
{
if (range == null)
{
throw new IllegalArgumentException("Range argument is mandatory");
}
// strip total if present - it does not give us anything useful
if (range.indexOf('/') != -1)
{
range = range.substring(0, range.indexOf('/'));
}
// find the separator
int separator = range.indexOf('-');
if (separator == -1)
{
throw new IllegalArgumentException("Invalid range: " + range);
}
try
{
// split range and parse values
long start = 0L;
if (separator != 0)
{
start = Long.parseLong(range.substring(0, separator));
}
long end = entityLength - 1L;
if (separator != range.length() - 1)
{
end = Long.parseLong(range.substring(separator + 1));
}
// return object to represent the byte-range
return new Range(contentType, start, end, entityLength);
}
catch (NumberFormatException err)
{
throw new IllegalArgumentException("Unable to parse range value: " + range);
}
}
/**
* Output the header bytes for a multi-part byte range header
*/
void outputHeader(ServletOutputStream os) throws IOException
{
// output multi-part boundry separator
os.println(MULTIPART_BYTERANGES_BOUNDRY_SEP);
// output content type and range size sub-header for this part
os.println(this.contentType);
os.println(getContentRange());
os.println();
}
/**
* @return the length in bytes of the byte range content including the header bytes
*/
int getLength()
{
// length in bytes of range plus it's header plus section marker and line feed bytes
return MULTIPART_BYTERANGES_BOUNDRY_SEP.length() + 2 +
this.contentType.length() + 2 +
getContentRange().length() + 4 + (int)(this.end - this.start + 1L) + 2;
}
/**
* @return the Content-Range header string value for this byte range
*/
private String getContentRange()
{
if (this.contentRange == null)
{
this.contentRange = "Content-Range: bytes " + Long.toString(this.start) + "-" +
Long.toString(this.end) + "/" + Long.toString(this.entityLength);
}
return this.contentRange;
}
@Override
public String toString()
{
return this.start + "-" + this.end;
}
/**
* @see java.lang.Comparable#compareTo(java.lang.Object)
*/
public int compareTo(Range o)
{
return this.start > o.start ? 1 : -1;
}
}
/** /**
* Helper to generate a URL to a content node for downloading content from the server. * Helper to generate a URL to a content node for downloading content from the server.
* *