Improve the HTTP JSON plugin README with more examples.

plugins/httpjson/README.md

@@ -2,7 +2,8 @@
 
 The httpjson plugin can collect data from remote URLs which respond with JSON. Then it flattens JSON and finds all numeric values, treating them as floats.
 
-For example, if you have a service called _mycollector_, which has HTTP endpoint for gathering stats http://my.service.com/_stats:
+For example, if you have a service called _mycollector_, which has HTTP endpoint for gathering stats at http://my.service.com/_stats, you would configure the HTTP JSON
+plugin like this:
 
 ```
 [[httpjson.services]]
@@ -16,11 +17,11 @@ For example, if you have a service called _mycollector_, which has HTTP endpoint
   method = "GET"
 ```
 
-The name is used as a prefix for the measurements.
+`name` is used as a prefix for the measurements.
 
-The `method` specifies HTTP method to use for requests.
+`method` specifies HTTP method to use for requests.
 
-You can specify which keys from server response should be considered as tags:
+You can also specify which keys from server response should be considered tags:
 
 ```
 [[httpjson.services]]
@@ -32,8 +33,6 @@ You can specify which keys from server response should be considered as tags:
   ]
 ```
 
-**NOTE**: tag values should be strings.
-
 You can also specify additional request parameters for the service:
 
 ```
@@ -47,11 +46,30 @@ You can also specify additional request parameters for the service:
 ```
 
 
-# Sample
+# Example:
+
+Let's say that we have a service named "mycollector" configured like this:
+
+```
+[httpjson]
+  [[httpjson.services]]
+    name = "mycollector"
+
+    servers = [
+      "http://my.service.com/_stats"
+    ]
+
+    # HTTP method to use (case-sensitive)
+    method = "GET"
+
+    tag_keys = ["service"]
+```
+
+which responds with the following JSON:
 
-Let's say that we have a service named "mycollector", which responds with:
 ```json
 {
+    "service": "service01",
     "a": 0.5,
     "b": {
         "c": "some text",
@@ -63,7 +81,68 @@ Let's say that we have a service named "mycollector", which responds with:
 
 The collected metrics will be:
 ```
-httpjson_mycollector_a value=0.5
+httpjson_mycollector_a,service='service01',server='http://my.service.com/_stats' value=0.5
-httpjson_mycollector_b_d value=0.1
+httpjson_mycollector_b_d,service='service01',server='http://my.service.com/_stats' value=0.1
-httpjson_mycollector_b_e value=5
+httpjson_mycollector_b_e,service='service01',server='http://my.service.com/_stats' value=5
+```
+
+# Example 2, Multiple Services:
+
+There is also the option to collect JSON from multiple services, here is an
+example doing that.
+
+```
+[httpjson]
+  [[httpjson.services]]
+    name = "mycollector1"
+
+    servers = [
+      "http://my.service1.com/_stats"
+    ]
+
+    # HTTP method to use (case-sensitive)
+    method = "GET"
+
+  [[httpjson.services]]
+    name = "mycollector2"
+
+    servers = [
+      "http://service.net/json/stats"
+    ]
+
+    # HTTP method to use (case-sensitive)
+    method = "POST"
+```
+
+The services respond with the following JSON:
+
+mycollector1:
+```json
+{
+    "a": 0.5,
+    "b": {
+        "c": "some text",
+        "d": 0.1,
+        "e": 5
+    }
+}
+```
+
+mycollector2:
+```json
+{
+    "load": 100,
+    "users": 1335
+}
+```
+
+The collected metrics will be:
+
+```
+httpjson_mycollector1_a,server='http://my.service.com/_stats' value=0.5
+httpjson_mycollector1_b_d,server='http://my.service.com/_stats' value=0.1
+httpjson_mycollector1_b_e,server='http://my.service.com/_stats' value=5
+
+httpjson_mycollector2_load,server='http://service.net/json/stats' value=100
+httpjson_mycollector2_users,server='http://service.net/json/stats' value=1335
 ```

plugins/httpjson/httpjson.go

@@ -127,7 +127,11 @@ func (h *HttpJson) Gather(acc plugins.Accumulator) error {
 //
 // Returns:
 //     error: Any error that may have occurred
-func (h *HttpJson) gatherServer(acc plugins.Accumulator, service Service, serverURL string) error {
+func (h *HttpJson) gatherServer(
+	acc plugins.Accumulator,
+	service Service,
+	serverURL string,
+) error {
 	resp, err := h.sendRequest(service, serverURL)
 	if err != nil {
 		return err

plugins/kafka_consumer/kafka_consumer.go

@@ -74,7 +74,11 @@ func (k *Kafka) Gather(acc plugins.Accumulator) error {
 			k.Consumer.Close()
 		}()
 
-		go readFromKafka(k.Consumer.Messages(), metricQueue, k.BatchSize, k.Consumer.CommitUpto, halt)
+		go readFromKafka(k.Consumer.Messages(),
+			metricQueue,
+			k.BatchSize,
+			k.Consumer.CommitUpto,
+			halt)
 	}
 
 	return emitMetrics(k, acc, metricQueue)
@@ -105,7 +109,13 @@ const millisecond = 1000000 * time.Nanosecond
 
 type ack func(*sarama.ConsumerMessage) error
 
-func readFromKafka(kafkaMsgs <-chan *sarama.ConsumerMessage, metricProducer chan<- []byte, maxBatchSize int, ackMsg ack, halt <-chan bool) {
+func readFromKafka(
+	kafkaMsgs <-chan *sarama.ConsumerMessage,
+	metricProducer chan<- []byte,
+	maxBatchSize int,
+	ackMsg ack,
+	halt <-chan bool,
+) {
 	batch := make([]byte, 0)
 	currentBatchSize := 0
 	timeout := time.After(500 * millisecond)