MQTT Consumer Input plugin

plugins/inputs/kafka_consumer/README.md

@@ -1,4 +1,4 @@
-# Kafka Consumer
+# Kafka Consumer Input Plugin
 
 The [Kafka](http://kafka.apache.org/) consumer plugin polls a specified Kafka
 topic and adds messages to InfluxDB. The plugin assumes messages follow the
@@ -6,6 +6,29 @@ line protocol. [Consumer Group](http://godoc.org/github.com/wvanbergen/kafka/con
 is used to talk to the Kafka cluster so multiple instances of telegraf can read
 from the same topic in parallel.
 
+## Configuration
+
+```toml
+# Read metrics from Kafka topic(s)
+[[inputs.kafka_consumer]]
+  ### topic(s) to consume
+  topics = ["telegraf"]
+  ### an array of Zookeeper connection strings
+  zookeeper_peers = ["localhost:2181"]
+  ### the name of the consumer group
+  consumer_group = "telegraf_metrics_consumers"
+  ### Maximum number of metrics to buffer between collection intervals
+  metric_buffer = 100000
+  ### Offset (must be either "oldest" or "newest")
+  offset = "oldest"
+
+  ### Data format to consume. This can be "json", "influx" or "graphite"
+  ### Each data format has it's own unique set of configuration options, read
+  ### more about them here:
+  ### https://github.com/influxdata/telegraf/blob/master/DATA_FORMATS_INPUT.md
+  data_format = "influx"
+```
+
 ## Testing
 
 Running integration tests requires running Zookeeper & Kafka. The following
@@ -16,9 +39,3 @@ To start Kafka & Zookeeper:
 ```
 docker run -d -p 2181:2181 -p 9092:9092 --env ADVERTISED_HOST=`boot2docker ip || docker-machine ip <your_machine_name>` --env ADVERTISED_PORT=9092 spotify/kafka
 ```
-
-To run tests:
-
-```
-go test
-```

plugins/inputs/kafka_consumer/kafka_consumer.go

@@ -19,8 +19,10 @@ type Kafka struct {
 	Topics         []string
 	ZookeeperPeers []string
 	Consumer       *consumergroup.ConsumerGroup
-	PointBuffer    int
-	Offset         string
+	MetricBuffer   int
+	// TODO remove PointBuffer, legacy support
+	PointBuffer int
+	Offset      string
 
 	parser parsers.Parser
 
@@ -30,7 +32,7 @@ type Kafka struct {
 	in <-chan *sarama.ConsumerMessage
 	// channel for all kafka consumer errors
 	errs <-chan *sarama.ConsumerError
-	// channel for all incoming parsed kafka points
+	// channel for all incoming parsed kafka metrics
 	metricC chan telegraf.Metric
 	done    chan struct{}
 
@@ -46,8 +48,8 @@ var sampleConfig = `
   zookeeper_peers = ["localhost:2181"]
   ### the name of the consumer group
   consumer_group = "telegraf_metrics_consumers"
-  ### Maximum number of points to buffer between collection intervals
-  point_buffer = 100000
+  ### Maximum number of metrics to buffer between collection intervals
+  metric_buffer = 100000
   ### Offset (must be either "oldest" or "newest")
   offset = "oldest"
 
@@ -104,10 +106,13 @@ func (k *Kafka) Start() error {
 	}
 
 	k.done = make(chan struct{})
-	if k.PointBuffer == 0 {
-		k.PointBuffer = 100000
+	if k.PointBuffer == 0 && k.MetricBuffer == 0 {
+		k.MetricBuffer = 100000
+	} else if k.PointBuffer > 0 {
+		// Legacy support of PointBuffer field TODO remove
+		k.MetricBuffer = k.PointBuffer
 	}
-	k.metricC = make(chan telegraf.Metric, k.PointBuffer)
+	k.metricC = make(chan telegraf.Metric, k.MetricBuffer)
 
 	// Start the kafka message reader
 	go k.receiver()
@@ -128,7 +133,7 @@ func (k *Kafka) receiver() {
 		case msg := <-k.in:
 			metrics, err := k.parser.Parse(msg.Value)
 			if err != nil {
-				log.Printf("Could not parse kafka message: %s, error: %s",
+				log.Printf("KAFKA PARSE ERROR\nmessage: %s\nerror: %s",
 					string(msg.Value), err.Error())
 			}
 
@@ -139,7 +144,7 @@ func (k *Kafka) receiver() {
 					continue
 				default:
 					log.Printf("Kafka Consumer buffer is full, dropping a metric." +
-						" You may want to increase the point_buffer setting")
+						" You may want to increase the metric_buffer setting")
 				}
 			}
 
@@ -166,10 +171,10 @@ func (k *Kafka) Stop() {
 func (k *Kafka) Gather(acc telegraf.Accumulator) error {
 	k.Lock()
 	defer k.Unlock()
-	npoints := len(k.metricC)
-	for i := 0; i < npoints; i++ {
-		point := <-k.metricC
-		acc.AddFields(point.Name(), point.Fields(), point.Tags(), point.Time())
+	nmetrics := len(k.metricC)
+	for i := 0; i < nmetrics; i++ {
+		metric := <-k.metricC
+		acc.AddFields(metric.Name(), metric.Fields(), metric.Tags(), metric.Time())
 	}
 	return nil
 }