Fix negative response times for MongoDB.

protos/mongodb/mongodb_structs.go

@@ -44,16 +44,13 @@ type MongodbStream struct {
 
 	data []byte
 
-	parseOffset   int
-	bytesReceived int
-
 	message *MongodbMessage
 }
 
 // Parser moves to next message in stream
 func (stream *MongodbStream) PrepareForNewMessage() {
 	stream.data = stream.data[stream.message.messageLength:]
-	stream.message = &MongodbMessage{Ts: stream.message.Ts}
+	stream.message = nil
 }
 
 // The private data of a parser instance

protos/redis/redis.go

@@ -293,7 +293,7 @@ func (redis *Redis) Init(test_mode bool, results chan common.MapStr) error {
 func (stream *RedisStream) PrepareForNewMessage() {
 	stream.data = stream.data[stream.parseOffset:]
 	stream.parseOffset = 0
-	stream.message = &RedisMessage{Ts: stream.message.Ts}
+	stream.message = nil
 	stream.message.Bulks = []string{}
 }
 

tests/test_0025_mongodb_basic.py

@@ -202,3 +202,20 @@ def test_write_errors(self):
         assert o["method"] == "insert"
         assert o["status"] == "Error"
         assert len(o["mongodb.error"]) > 0
+
+    def test_request_after_reply(self):
+        """
+        Tests that the response time is correctly captured when a single
+        reply is seen before the request.
+        This is a regression test for bug #216.
+        """
+        self.render_config_template(
+            mongodb_ports=[27017]
+        )
+        self.run_packetbeat(pcap="mongodb_reply_request_reply.pcap",
+                            debug_selectors=["mongodb"])
+
+        objs = self.read_output()
+        o = objs[0]
+        assert o["type"] == "mongodb"
+        assert o["responsetime"] >= 0