mongodb input: fix version 2.2 panic

closes #1628

CHANGELOG.md

@@ -20,6 +20,7 @@
 
 ### Bugfixes
 
+- [#1628](https://github.com/influxdata/telegraf/issues/1628): Fix mongodb input panic on version 2.2.
 
 ## v1.0 [unreleased]
 

internal/internal_test.go

@@ -118,7 +118,7 @@ func TestRandomSleep(t *testing.T) {
 	s = time.Now()
 	RandomSleep(time.Millisecond*50, make(chan struct{}))
 	elapsed = time.Since(s)
-	assert.True(t, elapsed < time.Millisecond*50)
+	assert.True(t, elapsed < time.Millisecond*100)
 
 	// test that shutdown is respected
 	s = time.Now()

plugins/inputs/kafka_consumer/kafka_consumer_test.go

@@ -43,7 +43,7 @@ func TestRunParser(t *testing.T) {
 	k.parser, _ = parsers.NewInfluxParser()
 	go k.receiver()
 	in <- saramaMsg(testMsg)
-	time.Sleep(time.Millisecond)
+	time.Sleep(time.Millisecond * 5)
 
 	assert.Equal(t, acc.NFields(), 1)
 }
@@ -58,7 +58,7 @@ func TestRunParserInvalidMsg(t *testing.T) {
 	k.parser, _ = parsers.NewInfluxParser()
 	go k.receiver()
 	in <- saramaMsg(invalidMsg)
-	time.Sleep(time.Millisecond)
+	time.Sleep(time.Millisecond * 5)
 
 	assert.Equal(t, acc.NFields(), 0)
 }
@@ -73,7 +73,7 @@ func TestRunParserAndGather(t *testing.T) {
 	k.parser, _ = parsers.NewInfluxParser()
 	go k.receiver()
 	in <- saramaMsg(testMsg)
-	time.Sleep(time.Millisecond)
+	time.Sleep(time.Millisecond * 5)
 
 	k.Gather(&acc)
 
@@ -92,7 +92,7 @@ func TestRunParserAndGatherGraphite(t *testing.T) {
 	k.parser, _ = parsers.NewGraphiteParser("_", []string{}, nil)
 	go k.receiver()
 	in <- saramaMsg(testMsgGraphite)
-	time.Sleep(time.Millisecond)
+	time.Sleep(time.Millisecond * 5)
 
 	k.Gather(&acc)
 
@@ -111,7 +111,7 @@ func TestRunParserAndGatherJSON(t *testing.T) {
 	k.parser, _ = parsers.NewJSONParser("kafka_json_test", []string{}, nil)
 	go k.receiver()
 	in <- saramaMsg(testMsgJSON)
-	time.Sleep(time.Millisecond)
+	time.Sleep(time.Millisecond * 5)
 
 	k.Gather(&acc)
 

plugins/inputs/mongodb/mongostat.go

@@ -514,7 +514,7 @@ func NewStatLine(oldMongo, newMongo MongoStatus, key string, all bool, sampleSec
 		returnVal.Command = diff(newStat.Opcounters.Command, oldStat.Opcounters.Command, sampleSecs)
 	}
 
-	if newStat.Metrics.TTL != nil && oldStat.Metrics.TTL != nil {
+	if newStat.Metrics != nil && newStat.Metrics.TTL != nil && oldStat.Metrics.TTL != nil {
 		returnVal.Passes = diff(newStat.Metrics.TTL.Passes, oldStat.Metrics.TTL.Passes, sampleSecs)
 		returnVal.DeletedDocuments = diff(newStat.Metrics.TTL.DeletedDocuments, oldStat.Metrics.TTL.DeletedDocuments, sampleSecs)
 	}