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@@ -1,2 +1,18 @@
 # auth
 auth system for ushio system
+
+
+## Key Logic
+ - three kinds of account: admin, user, visitor
+ - usr can be authed by email, phone, passwd
+ - after logined, the client id and secret can be generated and assigned
+ - every domain is an single app, it needs a new client id and secret.
+ - the app use the id and secret to get a time-expired token
+ - the client id and secret can be managed
+ 
+
+
+## Process Flow
+```
+
+```