patch for using namespaces with git-mediawiki

git-remote-mediawiki.namespaces.main.diff

patch works on:
* https://github.com/git/git/raw/9742fb7e53b2f3bd85b5f01e563aee2cad7e77b8/contrib/mw-to-git/git-remote-mediawiki.perl
* https://packages.debian.org/jessie/git-mediawiki

source:
* https://gist.github.com/anarcat/f821fa285c6b8b6b16a5

improvement:
* allows to get everything from main-namespace + selected namespaces/categories/pages

usage:
* git clone mediawiki::http://example.org/mediawiki -c 'remote.origin.namespaces=MAIN Howto Faq Todo'

--- git-remote-mediawiki.orig
+++ git-remote-mediawiki
@@ -18,6 +18,7 @@
 use Git::Mediawiki qw(clean_filename smudge_filename connect_maybe
 					EMPTY HTTP_CODE_OK);
 use DateTime::Format::ISO8601;
+use Scalar::Util;
 use warnings;
 
 # By default, use UTF-8 to communicate with Git and the user
@@ -64,6 +65,16 @@
 my @tracked_categories = split(/[ \n]/, run_git("config --get-all remote.${remotename}.categories"));
 chomp(@tracked_categories);
 
+# Just like @tracked_categories, but for MediaWiki namespaces.
+# "MAIN" is removed from @tracked_namespaces, but will be set as $main_namespace
+my $tracked_namespaces_str = run_git("config --get-all remote.${remotename}.namespaces");
+$tracked_namespaces_str =~ s/ ?MAIN ?//g;
+my @tracked_namespaces = split(/[ \n]/, $tracked_namespaces_str);
+chomp(@tracked_namespaces);
+
+# $main_namespace allows to get everything from main-namespace + selected namespaces/categories/pages (ignore $user_defined)
+my $main_namespace = run_git("config --get-all remote.${remotename}.namespaces") =~ /(^|[ ])MAIN([ ]|$)/;
+
 # Import media files on pull
 my $import_media = run_git("config --get --bool remote.${remotename}.mediaimport");
 chomp($import_media);
@@ -257,6 +268,23 @@
 	return;
 }
 
+sub get_mw_tracked_namespaces {
+    my $pages = shift;
+    foreach my $local_namespace (@tracked_namespaces) {
+        my $mw_pages = $mediawiki->list( {
+            action => 'query',
+            list => 'allpages',
+            apnamespace => get_mw_namespace_id($local_namespace),
+            aplimit => 'max' } )
+            || die $mediawiki->{error}->{code} . ': '
+                . $mediawiki->{error}->{details} . "\n";
+        foreach my $page (@{$mw_pages}) {
+            $pages->{$page->{title}} = $page;
+        }
+    }
+    return;
+}
+
 sub get_mw_all_pages {
 	my $pages = shift;
 	# No user-provided list, get the list of pages from the API.
@@ -320,7 +348,11 @@
 		$user_defined = 1;
 		get_mw_tracked_categories(\%pages);
 	}
-	if (!$user_defined) {
+    if (@tracked_namespaces) {
+        $user_defined = 1;
+        get_mw_tracked_namespaces(\%pages);
+    }
+	if (!$user_defined || $main_namespace) {
 		get_mw_all_pages(\%pages);
 	}
 	if ($import_media) {
@@ -1264,7 +1296,6 @@
 sub get_mw_namespace_id {
 	$mediawiki = connect_maybe($mediawiki, $remotename, $url);
 	my $name = shift;
-
 	if (!exists $namespace_id{$name}) {
 		# Look at configuration file, if the record for that namespace is
 		# already cached. Namespaces are stored in form:
@@ -1332,7 +1363,12 @@
 sub get_mw_namespace_id_for_page {
 	my $namespace = shift;
 	if ($namespace =~ /^([^:]*):/) {
-		return get_mw_namespace_id($namespace);
+		my ($ns, $id) = split(/:/, $namespace);
+		if (Scalar::Util::looks_like_number($id)) {
+			return get_mw_namespace_id($ns);
+		} else{
+			return
+		}
 	} else {
 		return;
 	}