[bin] automatically execute rover exec when needed

Author: mikz

apicast/bin/apicast

@@ -7,11 +7,21 @@ use Cwd qw(abs_path);
 
 my $apicast = $ENV{APICAST_DIR} || abs_path(dirname(abs_path(__FILE__)) . '/..');
 my $bindir = $apicast . '/bin';
-my $lua_path = $ENV{LUA_PATH} || ';';
+my $lua_path = $ENV{LUA_PATH};
+
+chomp(my $rover = `which rover`);
+if ($rover) { $rover = abs_path($rover) }
+
+if ($rover && !$lua_path) {
+    exec '/usr/bin/env', $rover, 'exec', $0, @ARGV
+} else {
+    $lua_path ||= ';';
+}
 
 chdir $apicast;
 
 $ENV{LUA_PATH} = "$apicast/src/?.lua;${lua_path}";
 
-exec '/usr/bin/env', 'resty',
-    "$bindir/cli", @ARGV;
+my @args = ('resty', "$bindir/cli", @ARGV);
+
+exec '/usr/bin/env', @args;