pass api url not site

ox/api.py

@@ -139,12 +139,17 @@ class API(object):
             shutil.move(tmpname, filename)
 
 
-def signin(site):
+def signin(url):
     import sys
     from getpass import getpass
     from .web import auth
 
-    api = API('https://%s/api/' % site)
+    if not url.startswith('http'):
+        site = url
+        url = 'https://%s/api/' % url
+    else:
+        site = url.split('/')[2]
+    api = API(url)
     update = False
     try:
         credentials = auth.get(site)