proxy.rb in ar-octopus-0.5.0

- old
+ new

@@ -1,48 +1,55 @@
 require "set"
 
 class Octopus::Proxy
-  attr_accessor :current_model, :current_shard, :current_group, :block, :using_enabled, :last_current_shard, :config
+  attr_accessor :config
 
-  def initialize(config)
+  def initialize(config = Octopus.config)
     initialize_shards(config)
     initialize_replication(config) if !config.nil? && config["replicated"]
   end
 
   def initialize_shards(config)
     @shards = HashWithIndifferentAccess.new
-    @groups = HashWithIndifferentAccess.new
+    @groups = {}
     @adapters = Set.new
-    @shards[:master] = ActiveRecord::Base.connection_pool()
-    @config = ActiveRecord::Base.connection_pool.connection.instance_variable_get(:@config)
-    @current_shard = :master
-    
+    @shards[:master] = ActiveRecord::Base.connection_pool_without_octopus()
+    @config = ActiveRecord::Base.connection_pool_without_octopus.connection.instance_variable_get(:@config)
+
     if !config.nil? && config.has_key?("verify_connection")
       @verify_connection = config["verify_connection"]
     else
       @verify_connection = false
     end
-    
+
     if !config.nil?
-      @entire_sharded = config['entire_sharded']  
-      shards_config = config[Octopus.rails_env()] 
+      @entire_sharded = config['entire_sharded']
+      shards_config = config[Octopus.rails_env()]
     end
-    
+
     shards_config ||= []
 
     shards_config.each do |key, value|
-      if value.has_key?("adapter")
+      if value.is_a?(String) && Octopus.rails32?
+        value = resolve_string_connection(value).merge(:octopus_shard => key)
         initialize_adapter(value['adapter'])
         @shards[key.to_sym] = connection_pool_for(value, "#{value['adapter']}_connection")
-      else
-        @groups[key.to_sym] = []
+      elsif value.is_a?(Hash) && value.has_key?("adapter")
+        value.merge!(:octopus_shard => key)
+        initialize_adapter(value['adapter'])
+        @shards[key.to_sym] = connection_pool_for(value, "#{value['adapter']}_connection")
+      elsif value.is_a?(Hash)
+        @groups[key.to_s] = []
 
         value.each do |k, v|
           raise "You have duplicated shard names!" if @shards.has_key?(k.to_sym)
+
           initialize_adapter(v['adapter'])
-          @shards[k.to_sym] = connection_pool_for(v, "#{v['adapter']}_connection")
-          @groups[key.to_sym] << k.to_sym
+          config_with_octopus_shard = v.merge(:octopus_shard => k)
+
+          @shards[k.to_sym] = connection_pool_for(config_with_octopus_shard, "#{v['adapter']}_connection")
+          @groups[key.to_s] << k.to_sym
         end
       end
     end
   end
 
@@ -51,51 +58,111 @@
     if config.has_key?("fully_replicated")
       @fully_replicated = config["fully_replicated"]
     else
       @fully_replicated = true
     end
-    @slaves_list = @shards.keys.map {|sym| sym.to_s}.sort 
-    @slaves_list.delete('master')   
+    @slaves_list = @shards.keys.map {|sym| sym.to_s}.sort
+    @slaves_list.delete('master')
+    @slave_index = 0
   end
 
+  def current_model
+    Thread.current["octopus.current_model"]
+  end
+
+  def current_model=(model)
+    Thread.current["octopus.current_model"] = model.is_a?(ActiveRecord::Base) ? model.class : model
+  end
+
+  def current_shard
+    Thread.current["octopus.current_shard"] ||= :master
+  end
+
   def current_shard=(shard_symbol)
     if shard_symbol.is_a?(Array)
       shard_symbol.each {|symbol| raise "Nonexistent Shard Name: #{symbol}" if @shards[symbol].nil? }
     else
       raise "Nonexistent Shard Name: #{shard_symbol}" if @shards[shard_symbol].nil?
     end
 
-    @current_shard = shard_symbol
+    Thread.current["octopus.current_shard"] = shard_symbol
   end
 
+  def current_group
+    Thread.current["octopus.current_group"]
+  end
+
   def current_group=(group_symbol)
-    if group_symbol.is_a?(Array)
-      group_symbol.each {|symbol| raise "Nonexistent Group Name: #{symbol}" if @groups[symbol].nil? }
-    else
-      raise "Nonexistent Group Name: #{group_symbol}" if @groups[group_symbol].nil?
+    # TODO: Error message should include all groups if given more than one bad name.
+    [group_symbol].flatten.compact.each do |group|
+      raise "Nonexistent Group Name: #{group}" unless has_group?(group)
     end
 
-    @current_group = group_symbol
+    Thread.current["octopus.current_group"] = group_symbol
   end
 
-  def current_model=(model)
-    @current_model = model.is_a?(ActiveRecord::Base) ? model.class : model
+  def block
+    Thread.current["octopus.block"]
   end
 
-  def select_connection()
-    @shards[shard_name].verify_active_connections! if @verify_connection 
+  def block=(block)
+    Thread.current["octopus.block"] = block
+  end
+
+  def last_current_shard
+    Thread.current["octopus.last_current_shard"]
+  end
+
+  def last_current_shard=(last_current_shard)
+    Thread.current["octopus.last_current_shard"] = last_current_shard
+  end
+
+  # Public: Whether or not a group exists with the given name converted to a
+  # string.
+  #
+  # Returns a boolean.
+  def has_group?(group)
+    @groups.has_key?(group.to_s)
+  end
+
+  # Public: Retrieves names of all loaded shards.
+  #
+  # Returns an array of shard names as symbols
+  def shard_names
+    @shards.keys
+  end
+
+  # Public: Retrieves the defined shards for a given group.
+  #
+  # Returns an array of shard names as symbols or nil if the group is not
+  # defined.
+  def shards_for_group(group)
+    @groups.fetch(group.to_s, nil)
+  end
+
+  def select_connection
+    @shards[shard_name].verify_active_connections! if @verify_connection
+    # Rails 3.1 sets automatic_reconnect to false when it removes
+    # connection pool.  Octopus can potentially retain a reference to a closed
+    # connection pool.  Previously, that would work since the pool would just
+    # reconnect, but in Rails 3.1 the flag prevents this.
+    if Octopus.rails31? || Octopus.rails32?
+      if !@shards[shard_name].automatic_reconnect
+        @shards[shard_name].automatic_reconnect = true
+      end
+    end
     @shards[shard_name].connection()
   end
 
   def shard_name
     current_shard.is_a?(Array) ? current_shard.first : current_shard
   end
-  
+
   def should_clean_table_name?
     @adapters.size > 1
   end
-  
+
   def run_queries_on_shard(shard, &block)
     older_shard = self.current_shard
     last_block = self.block
 
     begin
@@ -105,32 +172,31 @@
     ensure
       self.block = last_block || false
       self.current_shard = older_shard
     end
   end
-  
+
   def send_queries_to_multiple_shards(shards, &block)
     shards.each do |shard|
       self.run_queries_on_shard(shard, &block)
     end
   end
-  
+
   def clean_proxy()
-    @using_enabled = nil
-    @current_shard = :master
-    @current_group = nil
-    @block = false
+    self.current_shard = :master
+    self.current_group = nil
+    self.block = false
   end
-  
+
   def check_schema_migrations(shard)
-    if !ActiveRecord::Base.using(shard).connection.table_exists?(ActiveRecord::Migrator.schema_migrations_table_name())
-      ActiveRecord::Base.using(shard).connection.initialize_schema_migrations_table 
+    if !OctopusModel.using(shard).connection.table_exists?(ActiveRecord::Migrator.schema_migrations_table_name())
+      OctopusModel.using(shard).connection.initialize_schema_migrations_table
     end
   end
-  
+
   def transaction(options = {}, &block)
-    if @replicated && (current_model.read_inheritable_attribute(:replicated) || @fully_replicated)
+    if @replicated && (current_model.replicated || @fully_replicated)
       self.run_queries_on_shard(:master) do
         select_connection.transaction(options, &block)
       end
     else
       select_connection.transaction(options, &block)
@@ -142,23 +208,27 @@
       conn = select_connection()
       self.last_current_shard = self.current_shard
       clean_proxy()
       conn.send(method, *args, &block)
     elsif should_send_queries_to_replicated_databases?(method)
-      send_queries_to_selected_slave(method, *args, &block)      
+      send_queries_to_selected_slave(method, *args, &block)
     else
       select_connection().send(method, *args, &block)
     end
   end
 
   def respond_to?(method, include_private = false)
     super || select_connection.respond_to?(method, include_private)
   end
 
+  def connection_pool
+    return @shards[current_shard]
+  end
+
   protected
   def connection_pool_for(adapter, config)
-    ActiveRecord::ConnectionAdapters::ConnectionPool.new(ActiveRecord::Base::ConnectionSpecification.new(adapter, config))
+    ActiveRecord::ConnectionAdapters::ConnectionPool.new(ActiveRecord::Base::ConnectionSpecification.new(adapter.dup, config))
   end
 
   def initialize_adapter(adapter)
     @adapters << adapter
     begin
@@ -166,32 +236,33 @@
     rescue LoadError
       raise "Please install the #{adapter} adapter: `gem install activerecord-#{adapter}-adapter` (#{$!})"
     end
   end
 
+  def resolve_string_connection(spec)
+    ActiveRecord::Base::ConnectionSpecification::Resolver.new(spec, {}).spec.config.stringify_keys
+  end
+
   def should_clean_connection?(method)
     method.to_s =~ /insert|select|execute/ && !@replicated && !self.block
   end
 
   def should_send_queries_to_replicated_databases?(method)
-    @replicated && method.to_s =~ /select/ && !@block
+    @replicated && method.to_s =~ /select/ && !self.block
   end
 
-  def send_queries_to_selected_slave(method, *args, &block)        
+  def send_queries_to_selected_slave(method, *args, &block)
     old_shard = self.current_shard
-    
+
     begin
-      if current_model.read_inheritable_attribute(:replicated) || @fully_replicated
-        self.current_shard = @slaves_list.shift.to_sym
-        @slaves_list << self.current_shard
+      if current_model.replicated || @fully_replicated
+        self.current_shard = @slaves_list[@slave_index = (@slave_index + 1) % @slaves_list.length]
       else
         self.current_shard = :master
       end
-    
-      sql = select_connection().send(method, *args, &block)     
-      return sql    
+
+      select_connection.send(method, *args, &block)
     ensure
       self.current_shard = old_shard
-      @using_enabled = nil
     end
   end
 end