TT#65651 - Display correct DBIx error on duplicate subscriber

* Add check for provisioning subscriber
	   webusername so the API trhows the correct
	   error when encountering a duplicate

	 * This implementation relies on the DBIx
	   error to keep the database integrity

Change-Id: Ica3e2673cead28759ad25f5edb3f7ca0f32e1c1e

lib/NGCP/Panel/Controller/API/Subscribers.pm

@@ -406,10 +406,20 @@ sub POST :Allow {
                 c => $c, schema => $schema,
                 events_to_create => \@events_to_create,
             );
-        } catch(DBIx::Class::Exception $e where { /Duplicate entry '([^']+)' for key 'number_idx'/ }) {
-            $e =~ /Duplicate entry '([^']+)' for key 'number_idx'/;
-            $c->log->error("failed to create subscriber, number " . $c->qs($1) . " already exists"); # TODO: user, message, trace, ...
-            $self->error($c, HTTP_UNPROCESSABLE_ENTITY, "Number '" . $1 . "' already exists.", "Number already exists.");
+        } catch(DBIx::Class::Exception $e where { /Duplicate entry '([^']+)' for key ('number_idx'|'webuser_dom_idx')/ }) {
+            $e =~ /Duplicate entry '([^']+)' for key ('number_idx'|'webuser_dom_idx')/;
+            my $log_error;
+            my @http_errors;
+            if ($2 eq '\'number_idx\'') {
+                $log_error = "failed to create subscriber, number " . $c->qs($1) . " already exists";
+                @http_errors = ("Number '" . $1 . "' already exists.", "Number already exists.");
+            }
+            elsif ($2 eq '\'webuser_dom_idx\'') {
+                $log_error = "failed to create subscriber, webusername-domain combination " . $c->qs($1) . " already exists";
+                @http_errors = ("Webusername-Domain combination '" . $1 . "' already exists.", "Webusername-Domain combination already exists.");
+            }
+            $c->log->error($log_error); # TODO: user, message, trace, ...
+            $self->error($c, HTTP_UNPROCESSABLE_ENTITY, $http_errors[0], $http_errors[1]);
             last;
         } catch($e) {
             if (ref $error_info->{extended} eq 'HASH' && $error_info->{extended}->{response_code}) {