cgi: /$LISTNAME/ and /$LISTNAME/index.html are equal

This prevents ambiguity when switching URLs between static
file servers and CGI.

The /$LISTNAME/index.html URL appearing in the wild is inevitable
because of our static file server support.  Worst yet, there's
no easy/consistent way to get all installations detect and 301
them to the shorter /$LISTNAME/.  So we make the CGI support
/$LISTNAME/index.html.

The downside of this is the potential duplicate entry in all caches.

3 files changed, 11 insertions, 4 deletions

diff --git a/lib/PublicInbox/Feed.pm b/lib/PublicInbox/Feed.pm
index a6c1b9c1..da4cc04a 100644
--- a/lib/PublicInbox/Feed.pm
+++ b/lib/PublicInbox/Feed.pm
@@ -116,8 +116,12 @@ sub get_feedopts {
         if ($cgi) {
                 my $cgi_url = $cgi->self_url;
                 $url_base = $cgi_url;
-                $url_base =~ s!/?(?:index|all)\.atom\.xml\z!!;
-                $rv{atomurl} = $cgi_url;
+                if ($url_base =~ s!/(?:|index\.html)?\z!!) {
+                        $rv{atomurl} = "$url_base/index.atom.xml";
+                } else {
+                        $url_base =~ s!/?(?:index|all)\.atom\.xml\z!!;
+                        $rv{atomurl} = $cgi_url;
+                }
         } else {
                 $url_base = "http://example.com";
                 $rv{atomurl} = "$url_base/index.atom.xml";
diff --git a/public-inbox-cgi b/public-inbox-cgi
index cd79a4a7..828c94c1 100755
--- a/public-inbox-cgi
+++ b/public-inbox-cgi
@@ -55,7 +55,7 @@ sub main {
         # top-level indices and feeds
         if ($path_info eq "/") {
                 r404();
-        } elsif ($path_info =~ m!$LISTNAME_RE/?\z!o) {
+        } elsif ($path_info =~ m!$LISTNAME_RE(?:/|/index\.html)?\z!o) {
                 invalid_list(\%ctx, $1) || get_index(\%ctx, $cgi, 1);
         } elsif ($path_info =~ m!$LISTNAME_RE/index\.atom\.xml\z!o) {
                 invalid_list(\%ctx, $1) || get_atom(\%ctx, $cgi, 1);
diff --git a/t/cgi.t b/t/cgi.t
index a19f2cf1..93a48d00 100644
--- a/t/cgi.t
+++ b/t/cgi.t
@@ -119,10 +119,13 @@ EOF
         local $ENV{HOME} = $home;
         my $res = cgi_run("/test/");
         like($res->{head}, qr/Status: 200 OK/, "index returns 200");
+
+        my $idx = cgi_run("/test/index.html");
+        is_deeply($res, $idx,
+                '/$LISTNAME/ and /$LISTNAME/index.html are identical');
         # more checks in t/feed.t
 }
 
-
 {
         local $ENV{HOME} = $home;
         my $res = cgi_run("/test/m/blahblah\@example.com.txt");