# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1407692076 -7200
# Node ID 484cacbd943664328bd34bdf698a3ff66ce850e3
# Parent  debb4b2401fbcb2eebf2b83efa59e9d0cc24f6f9
Added support for attachment downloads via the /download/attachment URL syntax.

diff -r debb4b2401fb -r 484cacbd9436 README.txt
--- a/README.txt	Sun Aug 10 18:44:07 2014 +0200
+++ b/README.txt	Sun Aug 10 19:34:36 2014 +0200
@@ -264,11 +264,12 @@
 information.
 
 The redirect.py script, apart from supporting identifier-to-page redirects,
-also supports PDF page exports since the "doexportpage" action uses
-identifiers to indicate which page is to be exported. In an environment that
-uses .htaccess and mod_rewrite, the redirect.py script should also be deployed
-under separate names (such as export.py and exportpdf.py) so that it can
-discover whether it should be exporting a page instead of just showing it.
+also supports attachment downloads and PDF page exports, since both kinds of
+resource employ identifiers to indicate which page is involved. In an
+environment that uses .htaccess and mod_rewrite, the redirect.py script should
+also be deployed under separate names (such as export.py and exportpdf.py) so
+that it can discover whether it should be exporting a page instead of just
+showing it.
 
 The search.py script redirects search requests in a suitable form to the
 MoinMoin "fullsearch" action.
diff -r debb4b2401fb -r 484cacbd9436 config/mailmanwiki-redirect
--- a/config/mailmanwiki-redirect	Sun Aug 10 18:44:07 2014 +0200
+++ b/config/mailmanwiki-redirect	Sun Aug 10 19:34:36 2014 +0200
@@ -4,3 +4,4 @@
 ScriptAlias /spaces/flyingpdf/pdfpageexport.action "/var/www/mmwiki-scripts/redirect.py"
 ScriptAlias /dosearchsite.action "/var/www/mmwiki-scripts/search.py"
 ScriptAlias /dashboard.action "/var/www/mmwiki-scripts/dashboard.py"
+ScriptAlias /download/attachment "/var/www/mmwiki-scripts/redirect.py"
diff -r debb4b2401fb -r 484cacbd9436 config/mailmanwiki-redirect-htaccess
--- a/config/mailmanwiki-redirect-htaccess	Sun Aug 10 18:44:07 2014 +0200
+++ b/config/mailmanwiki-redirect-htaccess	Sun Aug 10 19:34:36 2014 +0200
@@ -21,3 +21,7 @@
 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
 RewriteRule ^dashboard.action /dashboard.py [PT,L,QSA]
+
+RewriteCond %{REQUEST_FILENAME} !-f
+RewriteCond %{REQUEST_FILENAME} !-d
+RewriteRule ^/download/attachment/(.*) /redirect.py/$1 [PT,L,QSA]
diff -r debb4b2401fb -r 484cacbd9436 scripts/redirect.py
--- a/scripts/redirect.py	Sun Aug 10 18:44:07 2014 +0200
+++ b/scripts/redirect.py	Sun Aug 10 19:34:36 2014 +0200
@@ -16,17 +16,32 @@
 # An empty string means that the wiki is anchored at the site root.
 
 URL_PREFIX = ""
+DOWNLOAD_SCRIPT = "/download.py"
 EXPORT_SCRIPT = "/export.py"
 EXPORT_PDF_SCRIPT = "/exportpdf.py"
 
-# See the scripts/tiny.py program for similar code in a stand-alone program.
+# Conversion of tiny identifiers to verbose identifiers.
 
 from base64 import b64decode
 from struct import unpack
 
 def identifier(s):
+
+    "Extract an identifier from the given string 's'."
+
+    # Isolate numeric identifiers for things like downloads:
+    # /download/attachment/<pageid>/<filename>?<args>
+
+    if s.split("/")[0].isdigit():
+        return s.split("/")[0]
+
+    # Reject strings that are too long for tiny identifiers.
+
     if len(s) > 6:
         return None
+
+    # Attempt to unpack tiny identifiers.
+
     bytes = b64decode(s.replace("-", "/").replace("_", "+") + "=" * (6 - len(s)))
     return str(unpack("<I", bytes + "\x00" * (4 - len(bytes)))[0])
 
@@ -47,8 +62,13 @@
 """ % (pageid and " (%s)" % pageid or "")
     sys.exit(0)
 
-def redirect(pagename, export=False):
-    location = "%s/%s%s" % (URL_PREFIX, quote(pagename), export and "?action=ExportPDF" or "")
+def redirect(pagename, download=None, export=False):
+    location = "%s/%s%s" % (
+        URL_PREFIX, quote(pagename),
+        download and "?action=AttachFile&do=get&target=%s" % download
+        or export and "?action=ExportPDF"
+        or ""
+        )
 
     print """\
 Status: 302 Redirect to page
@@ -81,6 +101,10 @@
     if pageid is None:
         fail(pageid)
 
+    download = (script.endswith(DOWNLOAD_SCRIPT) or
+                script.endswith("/download/attachment")
+               ) and path.rsplit("/", 1)[1] or None
+
     export = (script.endswith(EXPORT_SCRIPT) or
               script.endswith("/pages/doexportpage.action")
              ) and args.get("type", [""])[0] == "TYPE_PDF" or \
@@ -101,7 +125,7 @@
 
         # Redirect to the page.
 
-        redirect(pagename, export)
+        redirect(pagename, download, export)
 
     finally:
         f.close()