feat: Implement custom stickiness

.github/workflows/pull_request.yml

@@ -31,7 +31,7 @@ jobs:
       - name: Install dependencies
         run: bundle install
       - name: Download test cases
-        run: git clone --depth 5 --branch v3.3.0 https://github.com/Unleash/client-specification.git client-specification
+        run: git clone --depth 5 --branch v4.0.0 https://github.com/Unleash/client-specification.git client-specification
       - name: rubocop
         uses: reviewdog/action-rubocop@v2
         with:

lib/unleash/feature_toggle.rb

@@ -40,8 +40,7 @@ def get_variant(context, fallback_variant = Unleash::FeatureToggle.disabled_vari
       return Unleash::FeatureToggle.disabled_variant unless self.enabled && am_enabled?(context, true)
       return Unleash::FeatureToggle.disabled_variant if sum_variant_defs_weights <= 0
 
-      variant = variant_from_override_match(context)
-      variant = variant_from_weights(context) if variant.nil?
+      variant = variant_from_override_match(context) || variant_from_weights(context, resolve_stickiness)
 
       Unleash.toggle_metrics.increment_variant(self.name, variant.name) unless Unleash.configuration.disable_metrics
       variant
@@ -53,6 +52,10 @@ def self.disabled_variant
 
     private
 
+    def resolve_stickiness
+      self.variant_definitions&.map(&:stickiness)&.compact&.first || "default"
+    end
+
     # only check if it is enabled, do not do metrics
     def am_enabled?(context, default_result)
       result =
@@ -85,7 +88,8 @@ def sum_variant_defs_weights
       self.variant_definitions.map(&:weight).reduce(0, :+)
     end
 
-    def variant_salt(context)
+    def variant_salt(context, stickiness = "default")
+      return context.get_by_name(stickiness) unless stickiness == "default"
       return context.user_id unless context.user_id.to_s.empty?
       return context.session_id unless context.session_id.to_s.empty?
       return context.remote_address unless context.remote_address.to_s.empty?
@@ -100,8 +104,8 @@ def variant_from_override_match(context)
       Unleash::Variant.new(name: variant.name, enabled: true, payload: variant.payload)
     end
 
-    def variant_from_weights(context)
-      variant_weight = Unleash::Strategy::Util.get_normalized_number(variant_salt(context), self.name, sum_variant_defs_weights)
+    def variant_from_weights(context, stickiness)
+      variant_weight = Unleash::Strategy::Util.get_normalized_number(variant_salt(context, stickiness), self.name, sum_variant_defs_weights)
       prev_weights = 0
 
       variant_definition = self.variant_definitions
@@ -150,6 +154,7 @@ def initialize_variant_definitions(params)
             v.fetch('name', ''),
             v.fetch('weight', 0),
             v.fetch('payload', nil),
+            v.fetch('stickiness', nil),
             v.fetch('overrides', [])
           )
         end || []

lib/unleash/strategy/flexible_rollout.rb

@@ -38,16 +38,16 @@ def random
 
       def resolve_stickiness(stickiness, context)
         case stickiness
-        when 'userId'
-          context.user_id
-        when 'sessionId'
-          context.session_id
         when 'random'
           random
         when 'default'
           context.user_id || context.session_id || random
         else
-          nil
+          begin
+            context.get_by_name(stickiness)
+          rescue KeyError
+            nil
+          end
         end
       end
     end

lib/unleash/variant_definition.rb

@@ -2,13 +2,13 @@
 
 module Unleash
   class VariantDefinition
-    attr_accessor :name, :weight, :payload, :overrides
+    attr_accessor :name, :weight, :payload, :overrides, :stickiness
 
-    def initialize(name, weight = 0, payload = nil, overrides = [])
+    def initialize(name, weight = 0, payload = nil, stickiness = nil, overrides = [])
       self.name = name
       self.weight = weight
       self.payload = payload
-      # self.overrides = overrides
+      self.stickiness = stickiness
       self.overrides = (overrides || [])
         .select{ |v| v.is_a?(Hash) && v.has_key?('contextName') }
         .map{ |v| VariantOverride.new(v.fetch('contextName', ''), v.fetch('values', [])) } || []
@@ -19,7 +19,8 @@ def override_matches_context?(context)
     end
 
     def to_s
-      "<VariantDefinition: name=#{self.name},weight=#{self.weight},payload=#{self.payload},overrides=#{self.overrides}>"
+      "<VariantDefinition: name=#{self.name},weight=#{self.weight},payload=#{self.payload},stickiness=#{self.stickiness}" \
+          ",overrides=#{self.overrides}>"
     end
   end
 end

spec/unleash/client_spec.rb

@@ -376,6 +376,7 @@
         {
           name: "a",
           weight: 50,
+          stickiness: "default",
           payload: {
             type: "string",
             value: ""

spec/unleash/feature_toggle_spec.rb

@@ -156,11 +156,13 @@
         "variants" => [
           {
             "name" => "variant1",
-            "weight" => 50
+            "weight" => 50,
+            "stickiness" => "default"
           },
           {
             "name" => "variant2",
-            "weight" => 50
+            "weight" => 50,
+            "stickiness" => "default"
           }
         ],
         "createdAt" => "2019-01-24T10:41:45.236Z"
@@ -207,15 +209,18 @@
         "variants" => [
           {
             "name" => "variantA",
-            "weight" => 0
+            "weight" => 0,
+            "stickiness" => "default"
           },
           {
             "name" => "variantB",
-            "weight" => 10
+            "weight" => 10,
+            "stickiness" => "default"
           },
           {
             "name" => "variantC",
-            "weight" => 20
+            "weight" => 20,
+            "stickiness" => "default"
           }
         ],
         "createdAt" => "2019-01-24T10:41:45.236Z"
@@ -303,6 +308,7 @@
           {
             "name" => "variant1",
             "weight" => 50,
+            "stickiness" => "default",
             "payload" => {
               "type" => "string",
               "value" => "val1"
@@ -315,6 +321,7 @@
           {
             "name" => "variant2",
             "weight" => 50,
+            "stickiness" => "default",
             "payload" => {
               "type" => "string",
               "value" => "val2"
@@ -528,4 +535,90 @@
       expect(ret.name).to eq 'disabled'
     end
   end
+
+  describe 'FeatureToggle with custom stickiness' do
+    let(:feature_toggle) do
+      Unleash::FeatureToggle.new(
+        "name" => "toggleName",
+        "description" => nil,
+        "enabled" => true,
+        "variants" => [
+          {
+            "name" => "variant1",
+            "weight" => 25,
+            "stickiness" => "organization"
+          },
+          {
+            "name" => "variant2",
+            "weight" => 25,
+            "stickiness" => "organization"
+          },
+          {
+            "name" => "variant3",
+            "weight" => 25,
+            "stickiness" => "organization"
+          },
+          {
+            "name" => "variant4",
+            "weight" => 25,
+            "stickiness" => "organization"
+          }
+
+        ],
+        "createdAt" => "2019-01-24T10:41:45.236Z"
+      )
+    end
+
+    it 'should return variant1 organization 726' do
+      context = Unleash::Context.new(
+        properties: {
+          organization: '726'
+        }
+      )
+
+      expect(feature_toggle.get_variant(context)).to have_attributes(
+        name: "variant1",
+        enabled: true
+      )
+    end
+
+    it 'should return variant2 organization 48' do
+      context = Unleash::Context.new(
+        properties: {
+          organization: '48'
+        }
+      )
+
+      expect(feature_toggle.get_variant(context)).to have_attributes(
+        name: "variant2",
+        enabled: true
+      )
+    end
+
+    it 'should return variant3 organization 381' do
+      context = Unleash::Context.new(
+        properties: {
+          organization: '381'
+        }
+      )
+
+      expect(feature_toggle.get_variant(context)).to have_attributes(
+        name: "variant3",
+        enabled: true
+      )
+    end
+
+    it 'should return variant4 organization 222' do
+      context = Unleash::Context.new(
+        properties: {
+          organization: '222'
+        }
+      )
+
+      expect(feature_toggle.get_variant(context)).to have_attributes(
+        name: "variant4",
+        enabled: true
+      )
+    end
+  end
 end

spec/unleash/strategy/flexible_rollout_spec.rb

@@ -29,5 +29,37 @@
       expect(strategy.is_enabled?(params.merge({ 'rollout' => 15 }), unleash_context)).to be_truthy
       expect(strategy.is_enabled?(params.merge({ 'rollout' => 16 }), unleash_context)).to be_truthy
     end
+
+    it 'should be enabled when stickiness=customerId and customerId=61 and rollout=10' do
+      params = {
+        'groupId' => 'Demo',
+        'rollout' => 10,
+        'stickiness' => 'customerId'
+      }
+
+      custom_context = Unleash::Context.new(
+        properties: {
+          customer_id: '61'
+        }
+      )
+
+      expect(strategy.is_enabled?(params, custom_context)).to be_truthy
+    end
+
+    it 'should be disabled when stickiness=customerId and customerId=63 and rollout=10' do
+      params = {
+        'groupId' => 'Demo',
+        'rollout' => 10,
+        'stickiness' => 'customerId'
+      }
+
+      custom_context = Unleash::Context.new(
+        properties: {
+          customer_id: '63'
+        }
+      )
+
+      expect(strategy.is_enabled?(params, custom_context)).to be_falsey
+    end
   end
 end