Add personId partitionKey generator (#125)

* Add personId partitionKey generator

ask-sdk-dynamodb-persistence-adapter/ask_sdk_dynamodb/partition_keygen.py

@@ -59,3 +59,32 @@ def device_id_partition_keygen(request_envelope):
     except AttributeError:
         raise PersistenceException("Couldn't retrieve device id from "
                                    "request envelope, for partition key use")
+
+
+def person_id_partition_keygen(request_envelope):
+    # type: (RequestEnvelope) -> str
+    """Retrieve person id from request envelope, to use as object key.
+
+    This method retrieves the `person id` specific to a voice profile from
+    the request envelope if it exists, to be used as an object key. If it
+    doesn't exist, then the `user id` is returned instead.
+
+    :param request_envelope: Request Envelope passed during skill
+        invocation
+    :type request_envelope: ask_sdk_model.RequestEnvelope
+    :return: person Id retrieved from request envelope if exists, else
+        fall back on User Id
+    :rtype: str
+    :raises: :py:class:`ask_sdk_core.exceptions.PersistenceException`
+    """
+    try:
+        person_id = request_envelope.context.system.person.person_id
+    except AttributeError:
+        try:
+            person_id = user_id_partition_keygen(
+                request_envelope=request_envelope)
+        except PersistenceException:
+            raise PersistenceException(
+                "Couldn't retrieve person id or user id from request envelope, "
+                "for partition key use")
+    return person_id

ask-sdk-dynamodb-persistence-adapter/tests/unit/test_partition_keygen.py

@@ -17,11 +17,12 @@
 #
 import unittest
 
-from ask_sdk_model import RequestEnvelope, Context, User, Device
+from ask_sdk_model import RequestEnvelope, Context, User, Device, Person
 from ask_sdk_model.interfaces.system import SystemState
 from ask_sdk_core.exceptions import PersistenceException
 from ask_sdk_dynamodb.partition_keygen import (
-    user_id_partition_keygen, device_id_partition_keygen)
+    user_id_partition_keygen, device_id_partition_keygen,
+    person_id_partition_keygen)
 
 
 class TestPartitionKeyGenerators(unittest.TestCase):
@@ -31,6 +32,7 @@ def setUp(self):
         self.system = SystemState()
         self.user = User()
         self.device = Device()
+        self.person = Person()
 
     def test_valid_user_id_partition_keygen(self):
         self.user.user_id = "123"
@@ -138,6 +140,74 @@ def test_device_id_partition_keygen_raise_error_when_device_null(self):
             "null device provided in context.system of "
             "request envelope")
 
+    def test_valid_person_id_partition_keygen(self):
+        self.person.person_id = "123"
+        self.system.person = self.person
+        self.context.system = self.system
+        self.request_envelope.context = self.context
+
+        assert person_id_partition_keygen(self.request_envelope) == "123", (
+            "Person Id Partition Key Generation retrieved wrong person id from "
+            "valid person object in request envelope")
+
+    def test_person_id_partition_keygen_return_user_id_when_person_null(self):
+        self.person = None
+        self.system.person = self.person
+        self.user.user_id = "123"
+        self.system.user = self.user
+        self.context.system = self.system
+        self.request_envelope.context = self.context
+
+        assert person_id_partition_keygen(self.request_envelope) == "123", (
+            "Person Id Partition Key Generation retrieved wrong id from "
+            "request envelope when person is none and user id exists")
+
+    def test_person_id_partition_keygen_raise_error_when_person_null_user_null(
+            self):
+        self.context.system = self.system
+        self.request_envelope.context = self.context
+        with self.assertRaises(PersistenceException) as exc:
+            person_id_partition_keygen(request_envelope=self.request_envelope)
+
+        assert ("Couldn't retrieve person id or user id from request "
+                "envelope") in str(
+            exc.exception), (
+            "Person Id Partition Key Generation didn't throw exception when "
+            "person and user are null in request envelope")
+
+    def test_person_id_partition_keygen_raise_error_when_request_envelope_null(self):
+        with self.assertRaises(PersistenceException) as exc:
+            person_id_partition_keygen(request_envelope=None)
+
+        assert ("Couldn't retrieve person id or user id from request "
+                "envelope") in str(
+            exc.exception), (
+            "Person Id Partition Key Generation didn't throw exception when "
+            "null request envelope is provided")
+
+    def test_person_id_partition_keygen_raise_error_when_context_null(self):
+        with self.assertRaises(PersistenceException) as exc:
+            person_id_partition_keygen(request_envelope=self.request_envelope)
+
+        assert ("Couldn't retrieve person id or user id from request "
+                "envelope") in str(
+            exc.exception), (
+            "Person Id Partition Key Generation didn't throw exception when "
+            "null context provided in request envelope")
+
+    def test_person_id_partition_keygen_raise_error_when_system_null(self):
+        self.request_envelope.context = self.context
+
+        with self.assertRaises(PersistenceException) as exc:
+            person_id_partition_keygen(request_envelope=self.request_envelope)
+
+        assert ("Couldn't retrieve person id or user id from request "
+                "envelope") in str(
+            exc.exception), (
+            "Partition Id Partition Key Generation didn't throw exception when "
+            "null system provided in context of "
+            "request envelope")
+
     def tearDown(self):
         self.request_envelope = None
         self.context = None