diff --git a/deps/coro-websocket.lua b/deps/coro-websocket.lua
index 8841617..a3ea52a 100644
--- a/deps/coro-websocket.lua
+++ b/deps/coro-websocket.lua
@@ -19,7 +19,10 @@ local websocketCodec = require('websocket-codec')
 local net = require('coro-net')
 
 local function parseUrl(url)
-  local protocol, host, port, pathname = string.match(url, "^(wss?)://([^:/]+):?(%d*)(/?[^#?]*)")
+  local protocol, host, port, pathname = string.match(url, "^(wss?)://([^:/]+):?(%d*)(/?[^#]*)")
+  if not protocol or not host or host == "" then
+    return nil, "Invalid URL"
+  end
   local tls
   if protocol == "ws" then
     port = tonumber(port) or 80
@@ -30,6 +33,9 @@ local function parseUrl(url)
   else
     return nil, "Sorry, only ws:// or wss:// protocols supported"
   end
+  if pathname == "" then
+    pathname = "/"
+  end
   return {
     host = host,
     port = port,