[Rails 5] Add select_prepared to whitelist, duplicate 4.2 QueryCache …

…behavior (#19)

lib/replica_pools/engine.rb

@@ -15,12 +15,18 @@ class Engine < Rails::Engine
             :select_rows, :select, :verify!, :raw_connection, :active?, :reconnect!,
             :disconnect!, :reset_runtime, :log, :log_info
           ]
-        elsif [4, 5].include? ActiveRecord::VERSION::MAJOR
+        elsif ActiveRecord::VERSION::MAJOR == 4
           [
             :select_all, :select_one, :select_value, :select_values,
             :select_rows, :select, :verify!, :raw_connection, :active?, :reconnect!,
             :disconnect!, :reset_runtime, :log
           ]
+        elsif ActiveRecord::VERSION::MAJOR == 5
+          [
+           :select_all, :select_one, :select_value, :select_values,
+           :select_rows, :select, :select_prepared, :verify!, :raw_connection,
+           :active?, :reconnect!, :disconnect!, :reset_runtime, :log
+          ]
         else
           warn "Unsupported ActiveRecord version #{ActiveRecord.version}. Please whitelist the safe methods."
         end

lib/replica_pools/query_cache.rb

@@ -21,20 +21,29 @@ def #{method_name}(*a, &b)
     # connection for cache logic, but ultimately pass its query
     # through to whatever connection is current.
     def select_all(*args)
-      # there are more args, but we only care about arel, name, and binds for caching
-      arel, name, binds = args
-      if query_cache_enabled && !locked?(arel)
-        sql = to_sql(arel, binds)
-        args[0] = sql
-
-        if ActiveRecord::VERSION::STRING >= '5.1'
-          cache_sql(sql, name, binds) { route_to(current, :select_all, *args) }
-        else
-          cache_sql(sql, binds) { route_to(current, :select_all, *args) }
-        end
+      # there may be more args for Rails 5.0+, but we only care about arel, name, and binds for caching.
+      relation, name, raw_binds = args
+
+      if !query_cache_enabled || locked?(relation)
+        return route_to(current, :select_all, *args)
+      end
+
+      # duplicate binds_from_relation behavior introduced in 4.2.
+      if raw_binds.blank? && relation.is_a?(ActiveRecord::Relation)
+        arel, binds = relation.arel, relation.bind_values
+      else
+        arel, binds = relation, raw_binds
+      end
+
+      sql = to_sql(arel, binds)
+
+      args[0] = sql
+      args[2] = binds
 
+      if Gem::Version.new(ActiveRecord.version) < Gem::Version.new('5.1')
+        cache_sql(sql, binds) { route_to(current, :select_all, *args) }
       else
-        route_to(current, :select_all, *args)
+        cache_sql(sql, name, binds) { route_to(current, :select_all, *args) }
       end
     end
 

lib/replica_pools/version.rb

@@ -1,3 +1,3 @@
 module ReplicaPools
-  VERSION = "2.1.0.rc1"
+  VERSION = "2.1.0"
 end

spec/query_cache_spec.rb

@@ -2,7 +2,6 @@
 require_relative 'spec_helper'
 
 describe ReplicaPools::QueryCache do
-
   before(:each) do
     @sql = 'SELECT NOW()'
 
@@ -104,5 +103,4 @@ def executor
       end
     end
   end
-
 end