Some memoization

example.py

@@ -1,17 +1,53 @@
 import wideq
+import json
+
+STATE_FILE = 'wideq_state.json'
+
+
+def load_state():
+    """Load the current state data for this example.
+    """
+
+    try:
+        with open(STATE_FILE) as f:
+            return json.load(f)
+    except IOError:
+        return {}
+
+
+def save_state(state):
+    """Dump the current state to disk.
+    """
+
+    with open(STATE_FILE, 'w') as f:
+        json.dump(state, f)
 
 
 def example():
-    gw = wideq.gateway_info()
-    oauth_base = gw['empUri']
-    api_root = gw['thinqUri']
-    print(wideq.oauth_url(oauth_base))
+    state = load_state()
 
-    access_token = wideq.parse_oauth_callback(input())
-    print(access_token)
+    # Get the URLs for the API.
+    if 'oauth_base' not in state and 'api_root' not in state:
+        gw = wideq.gateway_info()
+        state['oauth_base'] = gw['empUri']
+        state['api_root'] = gw['thinqUri']
+    oauth_base = state['oauth_base']
+    api_root = state['api_root']
 
-    session_info = wideq.login(api_root, access_token)
-    print(session_info)
+    # If we don't have an access token, authenticate.
+    if 'access_token' not in state:
+        login_url = wideq.oauth_url(oauth_base)
+        print('Log in here:')
+        print(login_url)
+        print('Then paste the URL where the browser is redirected:')
+        callback_url = input()
+        state['access_token'] = wideq.parse_oauth_callback(callback_url)
+    access_token = state['access_token']
+
+    # If we don't have a session, log in.
+    if 'session_id' not in state:
+        session_info = wideq.login(api_root, access_token)
+        print(session_info)
 
 
 if __name__ == '__main__':