Merge pull request rails#50276 from fusion2004/fix-read-multi-raw-with-mem-cache-store

fix LocalCache#read_multi_entries not namespacing keys & not deserializing raw values correctly

Author: jonathanhefner

activesupport/lib/active_support/cache.rb

@@ -826,7 +826,7 @@ def serialize_entry(entry, **options)
           end
         end
 
-        def deserialize_entry(payload)
+        def deserialize_entry(payload, **)
           payload.nil? ? nil : @coder.load(payload)
         rescue DeserializationError
           nil

activesupport/lib/active_support/cache/strategy/local_cache.rb

@@ -131,17 +131,20 @@ def read_serialized_entry(key, raw: false, **options)
             end
           end
 
-          def read_multi_entries(keys, **options)
+          def read_multi_entries(names, **options)
             return super unless local_cache
 
-            local_entries = local_cache.read_multi_entries(keys)
+            keys_to_names = names.index_by { |name| normalize_key(name, options) }
+
+            local_entries = local_cache.read_multi_entries(keys_to_names.keys)
+            local_entries.transform_keys! { |key| keys_to_names[key] }
             local_entries.transform_values! do |payload|
-              deserialize_entry(payload)&.value
+              deserialize_entry(payload, **options)&.value
             end
-            missed_keys = keys - local_entries.keys
+            missed_names = names - local_entries.keys
 
-            if missed_keys.any?
-              local_entries.merge!(super(missed_keys, **options))
+            if missed_names.any?
+              local_entries.merge!(super(missed_names, **options))
             else
               local_entries
             end

activesupport/test/cache/behaviors/local_cache_behavior.rb

@@ -190,6 +190,7 @@ def test_local_cache_of_increment
     @cache.with_local_cache do
       @cache.write(key, 1, raw: true)
       @peek.write(key, 2, raw: true)
+
       @cache.increment(key)
 
       expected = @peek.read(key, raw: true)
@@ -205,6 +206,7 @@ def test_local_cache_of_decrement
       @peek.write(key, 3, raw: true)
 
       @cache.decrement(key)
+
       expected = @peek.read(key, raw: true)
       assert_equal 2, Integer(expected)
       assert_equal expected, @cache.read(key, raw: true)
@@ -230,7 +232,7 @@ def test_local_cache_of_read_multi
     other_value = SecureRandom.alphanumeric
     @cache.with_local_cache do
       @cache.write(key, value, raw: true)
-      @cache.write(other_key, other_value, raw: true)
+      @peek.write(other_key, other_value, raw: true)
       values = @cache.read_multi(key, other_key, raw: true)
       assert_equal value, @cache.read(key, raw: true)
       assert_equal other_value, @cache.read(other_key, raw: true)
@@ -239,6 +241,16 @@ def test_local_cache_of_read_multi
     end
   end
 
+  def test_local_cache_of_read_multi_prioritizes_local_entries
+    key = "key#{rand}"
+    @cache.with_local_cache do
+      @cache.write(key, "foo")
+      @cache.send(:bypass_local_cache) { @cache.write(key, "bar") }
+
+      assert_equal({ key => "foo" }, @cache.read_multi(key))
+    end
+  end
+
   def test_initial_object_mutation_after_write
     key = SecureRandom.uuid
     @cache.with_local_cache do