Support for downloading files in zip format (format=zip)

[PBruin]

I have been having some problems with downloading files from the Browser as none of the mime types have been specified in the repository I use. To make it easier to download files I have added a Zip Archive format next to the Original Format at the bottom of the file view in the Browser. This will download the file in zip format.
I also used the mime_type instead of the node.content_type for the 'format=raw' to prevent those ugly errors when trying to view a file has no mime_type defined in svn.
Do you think this could be added to the trunk?

Index: Browser.py
===================================================================
--- Browser.py	(revision 1579)
+++ Browser.py	(working copy)
@@ -174,7 +174,7 @@

         if req.args.get('format') == 'raw':
             req.send_response(200)
-            req.send_header('Content-Type', node.content_type)
+            req.send_header('Content-Type', mime_type)
             req.send_header('Content-Length', node.content_length)
             req.send_header('Last-Modified', util.http_date(node.last_modified))
             req.end_headers()
@@ -185,7 +185,27 @@
                 if not chunk:
                     break
                 req.write(chunk)
+        elif req.args.get('format') == 'zip':
+            req.send_header('Content-Type', 'application/zip')
+            req.send_header('Content-Disposition',
+                            'filename=%s.zip' % node.name )
+            req.end_headers()

+            try:
+                from cStringIO import StringIO
+            except ImportError:
+                from StringIO import StringIO
+            from zipfile import ZipFile, ZipInfo, ZIP_DEFLATED
+
+            buf = StringIO()
+            zipfile = ZipFile(buf, 'w', ZIP_DEFLATED)
+            zipinfo = ZipInfo()
+            zipinfo.filename = node.name
+            zipinfo.date_time = time.gmtime(node.last_modified)[:6]
+            zipinfo.compress_type = ZIP_DEFLATED
+            zipfile.writestr(zipinfo, node.get_content().read())
+            zipfile.close()
+            req.write(buf.getvalue())
         else:
             # Generate HTML preview
             content = util.to_utf8(node.get_content().read(DISP_MAX_FILE_SIZE),
@@ -205,6 +225,10 @@
             req.hdf['file.raw_href'] = raw_href
             add_link(req, 'alternate', raw_href, 'Original Format', mime_type)

+            add_link(req, 'alternate',
+                     self.env.href.browser(node.path, rev=rev and node.rev, format='zip'),
+                     'Zip Archive', 'application/zip' )
+
             req.display('browser.cs')

[Christopher Lenz]

This is basically a duplicate of #238.