Don’t try to connect to blacklisted resources

lib/makara/pool.rb

@@ -93,9 +93,13 @@ def send_to_all(method, *args, &block)
     # Provide a connection that is not blacklisted and connected. Handle any errors
     # that may occur within the block.
     def provide
-      provided_connection = self.next
+      if all_connections_blacklisted?
+        err = Makara::Errors::AllConnectionsBlacklisted.new(self, @blacklist_errors)
+        @blacklist_errors = []
+        raise err
+      end
 
-      # nil implies that it's blacklisted
+      provided_connection = self.next
       if provided_connection
 
         value = @proxy.error_handler.handle(provided_connection) do
@@ -105,12 +109,6 @@ def provide
         @blacklist_errors = []
 
         value
-
-      # if we've made any connections within this pool, we should report the blackout.
-      elsif connection_made?
-        err = Makara::Errors::AllConnectionsBlacklisted.new(self, @blacklist_errors)
-        @blacklist_errors = []
-        raise err
       else
         raise Makara::Errors::NoConnectionsAvailable.new(@role) unless @disabled
       end
@@ -122,16 +120,16 @@ def provide
       retry
     end
 
-
-
     protected
 
-
     # have we connected to any of the underlying connections.
     def connection_made?
       @connections.any?(&:_makara_connected?)
     end
 
+    def all_connections_blacklisted?
+      @connections.all?(&:_makara_blacklisted?)
+    end
 
     # Get the next non-blacklisted connection. If the proxy is setup
     # to be sticky, provide back the current connection assuming it is

spec/active_record/connection_adapters/makara_mysql2_adapter_spec.rb

@@ -163,7 +163,7 @@
 
       allow_any_instance_of(Makara::Strategies::RoundRobin).to receive(:single_one?){ true }
       Test::User.exists? # flush other (schema) things that need to happen
-      
+
       con = connection.slave_pool.connections.first
       if (ActiveRecord::VERSION::MAJOR == 5 && ActiveRecord::VERSION::MINOR <= 0)
         expect(con).to receive(:execute).with(/SELECT\s+1\s*(AS one)?\s+FROM .?users.?\s+LIMIT\s+.?1/, any_args).once.and_call_original

spec/active_record/connection_adapters/makara_postgis_adapter_spec.rb

@@ -118,8 +118,8 @@
         allow(ActiveRecord::Base).to receive(:postgis_connection).and_raise(StandardError.new('could not connect to server: Connection refused'))
 
         ActiveRecord::Base.establish_connection(config)
-        expect { connection.execute('SELECT * FROM users') }.to raise_error(Makara::Errors::NoConnectionsAvailable)
-        expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::NoConnectionsAvailable)
+        expect { connection.execute('SELECT * FROM users') }.to raise_error(Makara::Errors::AllConnectionsBlacklisted)
+        expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::AllConnectionsBlacklisted)
       end
     end
 
@@ -148,7 +148,7 @@
         ActiveRecord::Base.establish_connection(custom_config)
 
         connection.execute('SELECT * FROM users')
-        expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::NoConnectionsAvailable)
+        expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::AllConnectionsBlacklisted)
       end
     end
   end

spec/active_record/connection_adapters/makara_postgresql_adapter_spec.rb

@@ -77,7 +77,7 @@
 
       allow_any_instance_of(Makara::Strategies::RoundRobin).to receive(:single_one?){ true }
       Test::User.exists? # flush other (schema) things that need to happen
-      
+
       con = connection.slave_pool.connections.first
       if (ActiveRecord::VERSION::MAJOR == 4 && ActiveRecord::VERSION::MINOR >= 2) ||
          (ActiveRecord::VERSION::MAJOR == 5 && ActiveRecord::VERSION::MINOR <= 0)
@@ -100,8 +100,8 @@
       allow(ActiveRecord::Base).to receive(:postgresql_connection).and_raise(StandardError.new('could not connect to server: Connection refused'))
 
       ActiveRecord::Base.establish_connection(config)
-      expect { connection.execute('SELECT * FROM users') }.to raise_error(Makara::Errors::NoConnectionsAvailable)
-      expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::NoConnectionsAvailable)
+      expect { connection.execute('SELECT * FROM users') }.to raise_error(Makara::Errors::AllConnectionsBlacklisted)
+      expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::AllConnectionsBlacklisted)
     end
   end
 
@@ -130,7 +130,7 @@
       establish_connection(custom_config)
 
       connection.execute('SELECT * FROM users')
-      expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::NoConnectionsAvailable)
+      expect { connection.execute('INSERT INTO users (name) VALUES (\'John\')') }.to raise_error(Makara::Errors::AllConnectionsBlacklisted)
     end
   end