RUBY-1715 Log ismaster retries on monitoring connections

lib/mongo/retryable.rb

@@ -69,14 +69,19 @@ def read_with_retry(session = nil)
     #
     # @note This only retries read operations on socket errors.
     #
+    # @param [ Hash ] options Options.
     # @param [ Proc ] block The block to execute.
     #
+    # @option options [ String ] :retry_message Message to log when retrying.
+    #
     # @return [ Result ] The result of the operation.
     #
     # @since 2.2.6
-    def read_with_one_retry
+    def read_with_one_retry(options = nil)
       yield
-    rescue Error::SocketError, Error::SocketTimeoutError
+    rescue Error::SocketError, Error::SocketTimeoutError => e
+      retry_message = options && options[:retry_message]
+      log_retry(e, message: retry_message)
       yield
     end
 
@@ -200,8 +205,13 @@ def legacy_write_with_retry(server = nil, session = nil)
     end
 
     # Log a warning so that any application slow down is immediately obvious.
-    def log_retry(e)
-      Logger.logger.warn "Retry due to: #{e.class.name} #{e.message}"
+    def log_retry(e, options = nil)
+      message = if options && options[:message]
+        options[:message]
+      else
+        "Retry"
+      end
+      Logger.logger.warn "#{message} due to: #{e.class.name} #{e.message}"
     end
   end
 end

lib/mongo/server/monitor/connection.rb

@@ -128,7 +128,7 @@ def initialize(address, options = {})
         # @since 2.2.0
         def ismaster
           ensure_connected do |socket|
-            read_with_one_retry do
+            read_with_one_retry(retry_message: retry_message) do
               socket.write(ISMASTER_BYTES)
               Protocol::Message.deserialize(socket).documents[0]
             end
@@ -212,6 +212,10 @@ def handshake!
             reply
           end
         end
+
+        def retry_message
+          "Retrying ismaster on #{address}"
+        end
       end
     end
   end

spec/mongo/server/monitor/connection_spec.rb

@@ -116,4 +116,46 @@
       end
     end
   end
+
+  describe '#ismaster' do
+    let(:options) do
+      SpecConfig.instance.test_options
+    end
+
+    let(:result) { connection.ismaster }
+
+    it 'returns a hash' do
+      expect(result).to be_a(Hash)
+    end
+
+    it 'is successful' do
+      expect(result['ok']).to eq(1.0)
+    end
+
+    context 'network error during ismaster' do
+      let(:result) do
+        connection
+
+        socket = connection.send(:socket).send(:socket)
+        expect([Socket, OpenSSL::SSL::SSLSocket]).to include(socket.class)
+
+        expect(socket).to receive(:write).and_raise(IOError)
+        expect(socket).to receive(:write).and_call_original
+
+        connection.ismaster
+      end
+
+      it 'retries ismaster and is successful' do
+        expect(result).to be_a(Hash)
+        expect(result['ok']).to eq(1.0)
+      end
+
+      it 'logs the retry' do
+        expect(Mongo::Logger.logger).to receive(:warn) do |msg|
+          expect(msg).to match(/Retrying ismaster on #{connection.address}/)
+        end
+        expect(result).to be_a(Hash)
+      end
+    end
+  end
 end