simple handler dispatcher for hostname-based virtual hosting

1 files changed, 17 insertions, 0 deletions

diff --git a/handler.go b/handler.go
index bf6a21d..1c2d6dc 100644
--- a/handler.go
+++ b/handler.go
@@ -64,3 +64,20 @@ func Filter(
 		})
 	}
 }
+
+// VirtualHosts builds a handler which dispatches to site handlers by hostname.
+//
+// The 'catchall' argument may be used to specify a handler for use when no hostname
+// match is found. If the catchall is nil and no match is found, the VirtualHosts
+// handler returns a nil response.
+func VirtualHosts(hosts map[string]Handler, catchall Handler) Handler {
+	return HandlerFunc(func(ctx context.Context, request *Request) *Response {
+		if h := hosts[request.Hostname()]; h != nil {
+			return h.Handle(ctx, request)
+		}
+		if catchall != nil {
+			return catchall.Handle(ctx, request)
+		}
+		return nil
+	})
+}