Client support for custom stickiness (#143)

* Allow custom fields in FlexibleRollout Strategy.

* Allow custom fields in Variants.

* Add spec tests for "11-strategy-constraints-edge-cases.json"

* Add spec tests for "12-custom-stickiness.json".

* Update changelog.

* Add spec tests to Makefile.

Makefile

@@ -5,7 +5,7 @@ PROJECT_NAME = UnleashClient
 #-----------------------------------------------------------------------
 # Rules of Rules : Grouped rules that _doathing_
 #-----------------------------------------------------------------------
-test: lint pytest
+test: lint pytest specification-test
 
 precommit: clean generate-requirements
 
@@ -32,6 +32,10 @@ pytest:
 	export PYTHONPATH=${ROOT_DIR}: $$PYTHONPATH && \
 	py.test --flake8 --cov ${PROJECT_NAME} tests/unit_tests
 
+specification-test:
+	export PYTHONPATH=${ROOT_DIR}: $$PYTHONPATH && \
+	py.test tests/specification_tests
+
 tox-osx:
 	tox -c tox-osx.ini --parallel auto
 

UnleashClient/strategies/FlexibleRolloutStrategy.py

@@ -25,7 +25,7 @@ def apply(self, context: dict = None) -> bool:
                 calculated_percentage = normalized_hash(context['sessionId'], activation_group)
             else:
                 calculated_percentage = self.random_hash()
-        elif stickiness in ['userId', 'sessionId']:
+        elif stickiness in context.keys():
             calculated_percentage = normalized_hash(context[stickiness], activation_group)
         else:
             # This also handles the stickiness == random scenario.

UnleashClient/variants/Variants.py

@@ -34,16 +34,19 @@ def _apply_overrides(self, context: dict) -> dict:
         return override_variant
 
     @staticmethod
-    def _get_seed(context: dict) -> str:
+    def _get_seed(context: dict, stickiness_selector: str = "default") -> str:
         """Grabs seed value from context."""
         seed = str(random.random() * 10000)
 
-        if 'userId' in context:
-            seed = context['userId']
-        elif 'sessionId' in context:
-            seed = context['sessionId']
-        elif 'remoteAddress' in context:
-            seed = context['remoteAddress']
+        if stickiness_selector == "default":
+            if 'userId' in context:
+                seed = context['userId']
+            elif 'sessionId' in context:
+                seed = context['sessionId']
+            elif 'remoteAddress' in context:
+                seed = context['remoteAddress']
+        elif stickiness_selector in context.keys():
+            seed = context[stickiness_selector]
 
         return seed
 
@@ -53,6 +56,8 @@ def _format_variation(variation: dict) -> dict:
         del formatted_variation['weight']
         if 'overrides' in formatted_variation:
             del formatted_variation['overrides']
+        if 'stickiness' in formatted_variation:
+            del formatted_variation['stickiness']
         return formatted_variation
 
     def get_variant(self, context: dict) -> dict:
@@ -73,7 +78,9 @@ def get_variant(self, context: dict) -> dict:
             if total_weight <= 0:
                 return fallback_variant
 
-            target = utils.normalized_hash(self._get_seed(context), self.feature_name, total_weight)
+            stickiness_selector = self.variants[0]['stickiness'] if 'stickiness' in self.variants[0].keys() else "default"
+
+            target = utils.normalized_hash(self._get_seed(context, stickiness_selector), self.feature_name, total_weight)
             counter = 0
             for variation in self.variants:
                 counter += variation['weight']

docs/changelog.md

@@ -1,5 +1,8 @@
 ## Next version
 
+## Next
+* (Minor) Support custom stickiness for FlexibleRollout strategy and varients.
+
 ## v4.1.0
 * (Minor) Support project-based feature flag loading.
 

tests/specification_tests/test_11_strategy_constraints_edge_cases.py

@@ -0,0 +1,165 @@
+import uuid
+import json
+import pytest
+import responses
+from UnleashClient import UnleashClient
+from UnleashClient.constants import FEATURES_URL, METRICS_URL, REGISTER_URL
+from tests.utilities.testing_constants import URL, APP_NAME
+
+
+MOCK_JSON = """
+{
+    "version": 1,
+    "features": [
+        {
+            "name": "Feature.constraints.no_values",
+            "description": "Not enabled with constraints and no values",
+            "enabled": true,
+            "strategies": [
+                {
+                    "name": "default",
+                    "parameters": {},
+                    "constraints": [
+                        {
+                            "contextName": "environment",
+                            "operator": "IN",
+                            "values": []
+
+                        }
+                    ]
+                }
+            ]
+        },
+        {
+            "name": "Feature.constraints.no_values_NOT_IN",
+            "description": "Is enabled with constraints and NOT_IN empty values",
+            "enabled": true,
+            "strategies": [
+                {
+                    "name": "default",
+                    "parameters": {},
+                    "constraints": [
+                        {
+                            "contextName": "environment",
+                            "operator": "NOT_IN",
+                            "values": []
+
+                        }
+                    ]
+                }
+            ]
+        },
+        {
+            "name": "Feature.constraints.empty",
+            "description": "Is enabled with empty constraints array",
+            "enabled": true,
+            "strategies": [
+                {
+                    "name": "default",
+                    "parameters": {},
+                    "constraints": []
+                }
+            ]
+        }
+    ]
+}
+"""
+
+
+@pytest.fixture()
+def unleash_client():
+    unleash_client = UnleashClient(url=URL,
+                                   app_name=APP_NAME,
+                                   instance_id='pytest_%s' % uuid.uuid4())
+    yield unleash_client
+    unleash_client.destroy()
+
+
+@responses.activate
+def test_feature_constraints_novalue_defaultenv(unleash_client):
+    """
+    Feature.constraints.no_value should not be enabled in default environment
+    """
+    # Set up API
+    responses.add(responses.POST, URL + REGISTER_URL, json={}, status=202)
+    responses.add(responses.GET, URL + FEATURES_URL, json=json.loads(MOCK_JSON), status=200)
+    responses.add(responses.POST, URL + METRICS_URL, json={}, status=202)
+
+    # Tests
+    unleash_client.initialize_client()
+    assert not unleash_client.is_enabled("Feature.constraints.no_values", {'environment': 'default'})
+
+
+@responses.activate
+def test_feature_constraints_novalue_emptyenv(unleash_client):
+    """
+    Feature.constraints.no_value should not be enabled in empty environment
+    """
+    # Set up API
+    responses.add(responses.POST, URL + REGISTER_URL, json={}, status=202)
+    responses.add(responses.GET, URL + FEATURES_URL, json=json.loads(MOCK_JSON), status=200)
+    responses.add(responses.POST, URL + METRICS_URL, json={}, status=202)
+
+    # Tests
+    unleash_client.initialize_client()
+    assert not unleash_client.is_enabled("Feature.constraints.no_values", {})
+
+
+@responses.activate
+def test_feature_constraints_novalue_defaultenv_notin(unleash_client):
+    """
+    Feature.constraints.no_values_NOT_IN should be enabled in default environment
+    """
+    # Set up API
+    responses.add(responses.POST, URL + REGISTER_URL, json={}, status=202)
+    responses.add(responses.GET, URL + FEATURES_URL, json=json.loads(MOCK_JSON), status=200)
+    responses.add(responses.POST, URL + METRICS_URL, json={}, status=202)
+
+    # Tests
+    unleash_client.initialize_client()
+    assert unleash_client.is_enabled("Feature.constraints.no_values_NOT_IN", {'environment': 'default'})
+
+
+@responses.activate
+def test_feature_constraints_novalue_emptyenv_notin(unleash_client):
+    """
+    Feature.constraints.no_values_NOT_IN should be enabled in empty environment
+    """
+    # Set up API
+    responses.add(responses.POST, URL + REGISTER_URL, json={}, status=202)
+    responses.add(responses.GET, URL + FEATURES_URL, json=json.loads(MOCK_JSON), status=200)
+    responses.add(responses.POST, URL + METRICS_URL, json={}, status=202)
+
+    # Tests
+    unleash_client.initialize_client()
+    assert unleash_client.is_enabled("Feature.constraints.no_values_NOT_IN", {})
+
+
+@responses.activate
+def test_feature_constraints_empty_defaultenv(unleash_client):
+    """
+    Feature.constraints.empty should be enabled
+    """
+    # Set up API
+    responses.add(responses.POST, URL + REGISTER_URL, json={}, status=202)
+    responses.add(responses.GET, URL + FEATURES_URL, json=json.loads(MOCK_JSON), status=200)
+    responses.add(responses.POST, URL + METRICS_URL, json={}, status=202)
+
+    # Tests
+    unleash_client.initialize_client()
+    assert unleash_client.is_enabled("Feature.constraints.no_values_NOT_IN", {'environment': 'default'})
+
+
+@responses.activate
+def test_feature_constraints_empty_emptyenv(unleash_client):
+    """
+    Feature.constraints.empty should be enabled
+    """
+    # Set up API
+    responses.add(responses.POST, URL + REGISTER_URL, json={}, status=202)
+    responses.add(responses.GET, URL + FEATURES_URL, json=json.loads(MOCK_JSON), status=200)
+    responses.add(responses.POST, URL + METRICS_URL, json={}, status=202)
+
+    # Tests
+    unleash_client.initialize_client()
+    assert unleash_client.is_enabled("Feature.constraints.no_values_NOT_IN", {})