watch: use detect_indexlevel for unconfigured inboxes

I favor leaving the publicinbox.<name>.indexlevel parameter
out of config files to make it easier to alter and reduce
sources of truth.  It worked well in most cases, but
public-inbox-watch also needs to detect the indexlevel.

Moving the sub to InboxWritable (from Admin) probably makes
sense since it's a per-inbox attribute and allows -watch
to reuse it.

1 files changed, 27 insertions, 0 deletions

diff --git a/lib/PublicInbox/InboxWritable.pm b/lib/PublicInbox/InboxWritable.pm
index 17dfbe18..022e2a69 100644
--- a/lib/PublicInbox/InboxWritable.pm
+++ b/lib/PublicInbox/InboxWritable.pm
@@ -245,4 +245,31 @@ sub git_dir_latest {
                 "$self->{inboxdir}/git/$$max.git" : undef;
 }
 
+# for unconfigured inboxes
+sub detect_indexlevel ($) {
+        my ($ibx) = @_;
+
+        my $over = $ibx->over;
+        my $srch = $ibx->search;
+        delete @$ibx{qw(over search)}; # don't leave open FDs lying around
+
+        # brand new or never before indexed inboxes default to full
+        return 'full' unless $over;
+        my $l = 'basic';
+        return $l unless $srch;
+        if (my $xdb = $srch->xdb) {
+                $l = 'full';
+                my $m = $xdb->get_metadata('indexlevel');
+                if ($m eq 'medium') {
+                        $l = $m;
+                } elsif ($m ne '') {
+                        warn <<"";
+$ibx->{inboxdir} has unexpected indexlevel in Xapian: $m
+
+                }
+                $ibx->{-skip_docdata} = 1 if $xdb->get_metadata('skip_docdata');
+        }
+        $l;
+}
+
 1;