doc: add design documentation for WWW interface

Mainly, start with URL routes since that's what users usually
see, first.

diff --git a/Documentation/design_www.txt b/Documentation/design_www.txt
new file mode 100644 (file)
index 0000000..f6ed26a
--- /dev/null
+++ b/Documentation/design_www.txt
@@ -0,0 +1,12 @@
+URL naming
+----------
+
+/$LISTNAME/?before=$GIT_COMMIT                  -> HTML only
+/$LISTNAME/all.html?before=$GIT_COMMIT          -> HTML only, includes replies
+/$LISTNAME/index.atom.xml                       -> Atom feed
+/$LISTNAME/all.atom.xml                         -> Atom feed, includes replies
+/$LISTNAME/mid/$MESSAGE_ID.html                 -> HTML content
+/$LISTNAME/mid/$MESSAGE_ID.txt                  -> raw text
+
+We use file name suffixes on all of these (except /) so URLs may easily
+cached/memoized using a static file server.