Adding support for using the refresh token once an access token is expired

Author: Nick Bragdon

server/src/app/views.py

@@ -72,7 +72,7 @@ def authorizationCallback():
         configSettings = getConfigSettings(myEnv)
 
         # this gets the token from Medicare.gov once the 'user' authenticates their Medicare.gov account
-        response = getAccessToken(requestQuery.get('code'),requestQuery.get('state'),configSettings=configSettings,settings=settings)
+        authToken = getAccessToken(requestQuery.get('code'),requestQuery.get('state'),configSettings=configSettings,settings=settings)
 
         """DEVELOPER NOTES:
         * This is where you would most likely place some type of
@@ -82,7 +82,6 @@ def authorizationCallback():
         * Here we are however, just updating the loggedInUser we pulled from our MockDb, but we aren't persisting that change
         * back into our mocked DB, normally you would want to do this
         """
-        authToken = json.loads(response.text)
 
         #Here we are grabbing the mocked 'user' for our application
         # to be able to store the access token for that user

server/src/utils/bb2Util.py

@@ -6,6 +6,7 @@
 import requests
 from requests_toolbelt.multipart.encoder import MultipartEncoder
 import urllib
+import datetime
 
 """ DEVELOPER NOTES:
 * This is our mocked Data Service layer for both the BB2 API
@@ -53,11 +54,30 @@ def getAccessToken(code, state, configSettings, settings):
     # and provide a header with the content type including the boundary or this call will fail
     mp_encoder = MultipartEncoder(PARAMS)
     myResponse = requests.post(url=BB2_ACCESS_TOKEN_URL,data=mp_encoder,headers={'content-type':mp_encoder.content_type})
-    return myResponse
+    response_json = myResponse.json()
+    response_json['expires_at'] = datetime.datetime.now() + datetime.timedelta(seconds=response_json['expires_in'])
+    return response_json
+
+def refreshAccessToken(refresh_token, configSettings, settings):
+    BB2_ACCESS_TOKEN_URL = configSettings.get('bb2BaseUrl')+'/'+settings.version+'/o/token/'
+    params = {
+        'client_id':configSettings.get('bb2ClientId'),
+        'grant_type': 'refresh_token',
+        'refresh_token': refresh_token
+    }
+
+    myResponse = requests.post(url=BB2_ACCESS_TOKEN_URL, params=params, auth=(configSettings.get('bb2ClientId'), configSettings.get('bb2ClientSecret')))
+    response_json = myResponse.json()
+    response_json['expires_at'] = datetime.datetime.now() + datetime.timedelta(seconds=response_json['expires_in'])
+    return response_json
 
 # this function is used to query eob data for the authenticated Medicare.gov
 #  user and returned - we are then storing in a mocked DB
 def getBenefitData(settings, configsSettings, query, loggedInUser):
+    if (datetime.datetime.now() > loggedInUser.get('authToken').get('expires_at')):
+        updated_auth_token = refreshAccessToken(loggedInUser.get('authToken').get('refresh_token'), configsSettings, settings)
+        loggedInUser.update({'authToken':updated_auth_token})
+
     PARAMS = {
         'code':query.get('code'),
         'state':query.get('state')