All The Get Alls

.rubocop.yml

@@ -40,3 +40,6 @@ Style/TrailingCommaInLiteral:
 
 RSpec/InstanceVariable:
   Enabled: false
+
+Style/AccessorMethodName:
+  Enabled: false

lib/flipper/adapters/active_record.rb

@@ -86,6 +86,21 @@ def get_multi(features)
         result
       end
 
+      def get_all
+        joins = <<-EOJ
+          INNER JOIN #{@feature_class.table_name}
+          ON #{@feature_class.table_name}.key = #{@gate_class.table_name}.feature_key
+        EOJ
+        db_gates = @gate_class.joins(joins).all.to_a
+        grouped_db_gates = db_gates.group_by(&:feature_key)
+        result = Hash.new { |hash, key| hash[key] = default_config }
+        features = grouped_db_gates.keys.map { |key| Flipper::Feature.new(key, self) }
+        features.each do |feature|
+          result[feature.key] = result_for_feature(feature, grouped_db_gates[feature.key])
+        end
+        result
+      end
+
       # Public: Enables a gate for a given thing.
       #
       # feature - The Flipper::Feature for the gate.

lib/flipper/adapters/active_support_cache_store.rb

@@ -9,6 +9,7 @@ class ActiveSupportCacheStore
       Version = 'v1'.freeze
       Namespace = "flipper/#{Version}".freeze
       FeaturesKey = "#{Namespace}/features".freeze
+      GetAllKey = "#{Namespace}/get_all".freeze
 
       # Private
       def self.key_for(key)
@@ -27,14 +28,12 @@ def initialize(adapter, cache, expires_in: nil)
         @name = :active_support_cache_store
         @cache = cache
         @write_options = {}
-        @write_options.merge!(expires_in: expires_in) if expires_in
+        @write_options[:expires_in] = expires_in if expires_in
       end
 
       # Public
       def features
-        @cache.fetch(FeaturesKey, @write_options) do
-          @adapter.features
-        end
+        read_feature_keys
       end
 
       # Public
@@ -67,17 +66,21 @@ def get(feature)
       end
 
       def get_multi(features)
-        keys = features.map { |feature| key_for(feature.key) }
-        result = @cache.read_multi(keys)
-        uncached_features = features.reject { |feature| result[feature.key] }
-        if uncached_features.any?
-          response = @adapter.get_multi(uncached_features)
+        read_many_features(features)
+      end
+
+      def get_all
+        if @cache.write(GetAllKey, Time.now.to_i, @write_options.merge(unless_exist: true))
+          response = @adapter.get_all
           response.each do |key, value|
             @cache.write(key_for(key), value, @write_options)
-            result[key] = value
           end
+          @cache.write(FeaturesKey, response.keys.to_set, @write_options)
+          response
+        else
+          features = read_feature_keys.map { |key| Flipper::Feature.new(key, self) }
+          read_many_features(features)
         end
-        result
       end
 
       ## Public
@@ -99,6 +102,33 @@ def disable(feature, gate, thing)
       def key_for(key)
         self.class.key_for(key)
       end
+
+      # Internal: Returns an array of the known feature keys.
+      def read_feature_keys
+        @cache.fetch(FeaturesKey, @write_options) { @adapter.features }
+      end
+
+      # Internal: Given an array of features, attempts to read through cache in
+      # as few network calls as possible.
+      def read_many_features(features)
+        keys = features.map { |feature| key_for(feature.key) }
+        cache_result = @cache.read_multi(*keys)
+        uncached_features = features.reject { |feature| cache_result[key_for(feature)] }
+
+        if uncached_features.any?
+          response = @adapter.get_multi(uncached_features)
+          response.each do |key, value|
+            @cache.write(key_for(key), value, @write_options)
+            cache_result[key_for(key)] = value
+          end
+        end
+
+        result = {}
+        features.each do |feature|
+          result[feature.key] = cache_result[key_for(feature.key)]
+        end
+        result
+      end
     end
   end
 end

lib/flipper/adapters/dalli.rb

@@ -10,6 +10,7 @@ class Dalli
       Version = 'v1'.freeze
       Namespace = "flipper/#{Version}".freeze
       FeaturesKey = "#{Namespace}/features".freeze
+      GetAllKey = "#{Namespace}/get_all".freeze
 
       # Private
       def self.key_for(key)
@@ -22,6 +23,9 @@ def self.key_for(key)
       # Public: The name of the adapter.
       attr_reader :name
 
+      # Public: The ttl for all cached data.
+      attr_reader :ttl
+
       # Public
       def initialize(adapter, cache, ttl = 0)
         @adapter = adapter
@@ -32,9 +36,7 @@ def initialize(adapter, cache, ttl = 0)
 
       # Public
       def features
-        @cache.fetch(FeaturesKey, @ttl) do
-          @adapter.features
-        end
+        read_feature_keys
       end
 
       # Public
@@ -67,19 +69,21 @@ def get(feature)
       end
 
       def get_multi(features)
-        keys = features.map { |feature| key_for(feature.key) }
-        result = @cache.get_multi(keys)
-        uncached_features = features.reject { |feature| result[key_for(feature.key)] }
+        read_many_features(features)
+      end
 
-        if uncached_features.any?
-          response = @adapter.get_multi(uncached_features)
+      def get_all
+        if @cache.add(GetAllKey, Time.now.to_i, @ttl)
+          response = @adapter.get_all
           response.each do |key, value|
             @cache.set(key_for(key), value, @ttl)
-            result[key] = value
           end
+          @cache.set(FeaturesKey, response.keys.to_set, @ttl)
+          response
+        else
+          features = read_feature_keys.map { |key| Flipper::Feature.new(key, self) }
+          read_many_features(features)
         end
-
-        result
       end
 
       # Public
@@ -101,6 +105,32 @@ def disable(feature, gate, thing)
       def key_for(key)
         self.class.key_for(key)
       end
+
+      def read_feature_keys
+        @cache.fetch(FeaturesKey, @ttl) { @adapter.features }
+      end
+
+      # Internal: Given an array of features, attempts to read through cache in
+      # as few network calls as possible.
+      def read_many_features(features)
+        keys = features.map { |feature| key_for(feature.key) }
+        cache_result = @cache.get_multi(keys)
+        uncached_features = features.reject { |feature| cache_result[key_for(feature.key)] }
+
+        if uncached_features.any?
+          response = @adapter.get_multi(uncached_features)
+          response.each do |key, value|
+            @cache.set(key_for(key), value, @ttl)
+            cache_result[key_for(key)] = value
+          end
+        end
+
+        result = {}
+        features.each do |feature|
+          result[feature.key] = cache_result[key_for(feature.key)]
+        end
+        result
+      end
     end
   end
 end

lib/flipper/adapters/memoizable.rb

@@ -9,6 +9,7 @@ class Memoizable < SimpleDelegator
       include ::Flipper::Adapter
 
       FeaturesKey = :flipper_features
+      GetAllKey = :all_memoized
 
       # Internal
       attr_reader :cache
@@ -19,14 +20,18 @@ class Memoizable < SimpleDelegator
       # Internal: The adapter this adapter is wrapping.
       attr_reader :adapter
 
+      # Private
+      def self.key_for(key)
+        "feature/#{key}"
+      end
+
       # Public
       def initialize(adapter, cache = nil)
         super(adapter)
         @adapter = adapter
         @name = :memoizable
         @cache = cache || {}
         @memoize = false
-        @all_fetched = false
       end
 
       # Public
@@ -63,7 +68,7 @@ def clear(feature)
       # Public
       def get(feature)
         if memoizing?
-          cache.fetch(feature.key) { cache[feature.key] = @adapter.get(feature) }
+          cache.fetch(key_for(feature.key)) { cache[key_for(feature.key)] = @adapter.get(feature) }
         else
           @adapter.get(feature)
         end
@@ -72,18 +77,18 @@ def get(feature)
       # Public
       def get_multi(features)
         if memoizing?
-          uncached_features = features.reject { |feature| cache[feature.key] }
+          uncached_features = features.reject { |feature| cache[key_for(feature.key)] }
 
           if uncached_features.any?
             response = @adapter.get_multi(uncached_features)
             response.each do |key, hash|
-              cache[key] = hash
+              cache[key_for(key)] = hash
             end
           end
 
           result = {}
           features.each do |feature|
-            result[feature.key] = cache[feature.key]
+            result[feature.key] = cache[key_for(feature.key)]
           end
           result
         else
@@ -93,20 +98,25 @@ def get_multi(features)
 
       def get_all
         if memoizing?
-          unless @all_fetched
-            result = @adapter.get_all
-            result.each do |key, value|
-              cache[key] = value
+          response = nil
+          if cache[GetAllKey]
+            response = {}
+            cache[FeaturesKey].each do |key|
+              response[key] = cache[key_for(key)]
             end
-            cache[FeaturesKey] = result.keys.to_set
-            @all_fetched = true
+          else
+            response = @adapter.get_all
+            response.each do |key, value|
+              cache[key_for(key)] = value
+            end
+            cache[FeaturesKey] = response.keys.to_set
+            cache[GetAllKey] = true
           end
 
-          result = {}
-          features.each do |key|
-            result[key] = cache[key]
-          end
-          result
+          # Ensures that looking up other features that do not exist doesn't
+          # result in N+1 adapter calls.
+          response.default_proc = ->(memo, key) { memo[key] = default_config }
+          response
         else
           @adapter.get_all
         end
@@ -130,7 +140,6 @@ def disable(feature, gate, thing)
       #
       # value - The Boolean that decides if local caching is on.
       def memoize=(value)
-        @all_fetched = false
         cache.clear
         @memoize = value
       end
@@ -142,8 +151,12 @@ def memoizing?
 
       private
 
+      def key_for(key)
+        self.class.key_for(key)
+      end
+
       def expire_feature(feature)
-        cache.delete(feature.key) if memoizing?
+        cache.delete(key_for(feature.key)) if memoizing?
       end
 
       def expire_features_set