Rabbitmq plugin: connection-related metrics. (influxdata#1908)

* Rabbitmq plugin: connection-related metrics.

* Run go fmt.

plugins/inputs/rabbitmq/rabbitmq.go

@@ -50,8 +50,9 @@ type RabbitMQ struct {
 	ClientTimeout         internal.Duration `toml:"client_timeout"`
 
 	// InsecureSkipVerify bool
-	Nodes  []string
-	Queues []string
+	Nodes       []string
+	Queues      []string
+	Connections []string
 
 	Client *http.Client
 }
@@ -135,10 +136,22 @@ type Node struct {
 	SocketsUsed   int64 `json:"sockets_used"`
 }
 
+// Connection ...
+type Connection struct {
+	Name         string
+	State        string
+	Vhost        string
+	Host         string
+	Node         string
+	ReceiveCount int64 `json:"recv_cnt"`
+	SendCount    int64 `json:"send_cnt"`
+	SendPend     int64 `json:"send_pend"`
+}
+
 // gatherFunc ...
 type gatherFunc func(r *RabbitMQ, acc telegraf.Accumulator, errChan chan error)
 
-var gatherFunctions = []gatherFunc{gatherOverview, gatherNodes, gatherQueues}
+var gatherFunctions = []gatherFunc{gatherOverview, gatherNodes, gatherQueues, gatherConnections}
 
 var sampleConfig = `
   # url = "http://localhost:15672"
@@ -380,6 +393,42 @@ func gatherQueues(r *RabbitMQ, acc telegraf.Accumulator, errChan chan error) {
 	errChan <- nil
 }
 
+func gatherConnections(r *RabbitMQ, acc telegraf.Accumulator, errChan chan error) {
+	// Gather information about connections
+	connections := make([]Connection, 0)
+	err := r.requestJSON("/api/connections", &connections)
+	if err != nil {
+		errChan <- err
+		return
+	}
+
+	for _, connection := range connections {
+		if !r.shouldGatherConnection(connection) {
+			continue
+		}
+		tags := map[string]string{
+			"url":        r.URL,
+			"connection": connection.Name,
+			"vhost":      connection.Vhost,
+			"host":       connection.Host,
+			"node":       connection.Node,
+		}
+
+		acc.AddFields(
+			"rabbitmq_connection",
+			map[string]interface{}{
+				"recv_cnt":  connection.ReceiveCount,
+				"send_cnt":  connection.SendCount,
+				"send_pend": connection.SendPend,
+				"state":     connection.State,
+			},
+			tags,
+		)
+	}
+
+	errChan <- nil
+}
+
 func (r *RabbitMQ) shouldGatherNode(node Node) bool {
 	if len(r.Nodes) == 0 {
 		return true
@@ -408,6 +457,20 @@ func (r *RabbitMQ) shouldGatherQueue(queue Queue) bool {
 	return false
 }
 
+func (r *RabbitMQ) shouldGatherConnection(connection Connection) bool {
+	if len(r.Connections) == 0 {
+		return true
+	}
+
+	for _, name := range r.Connections {
+		if name == connection.Name {
+			return true
+		}
+	}
+
+	return false
+}
+
 func init() {
 	inputs.Add("rabbitmq", func() telegraf.Input {
 		return &RabbitMQ{

plugins/inputs/rabbitmq/rabbitmq_test.go

@@ -374,6 +374,57 @@ const sampleQueuesResponse = `
 ]
 `
 
+const sampleConnectionsResponse = `
+[
+  {
+    "recv_oct": 166055,
+    "recv_oct_details": {
+      "rate": 0
+    },
+    "send_oct": 589,
+    "send_oct_details": {
+      "rate": 0
+    },
+    "recv_cnt": 124,
+    "send_cnt": 7,
+    "send_pend": 0,
+    "state": "running",
+    "channels": 1,
+    "type": "network",
+    "node": "rabbit@ip-10-0-12-133",
+    "name": "10.0.10.8:32774 -> 10.0.12.131:5672",
+    "port": 5672,
+    "peer_port": 32774,
+    "host": "10.0.12.131",
+    "peer_host": "10.0.10.8",
+    "ssl": false,
+    "peer_cert_subject": null,
+    "peer_cert_issuer": null,
+    "peer_cert_validity": null,
+    "auth_mechanism": "AMQPLAIN",
+    "ssl_protocol": null,
+    "ssl_key_exchange": null,
+    "ssl_cipher": null,
+    "ssl_hash": null,
+    "protocol": "AMQP 0-9-1",
+    "user": "workers",
+    "vhost": "main",
+    "timeout": 0,
+    "frame_max": 131072,
+    "channel_max": 65535,
+    "client_properties": {
+      "product": "py-amqp",
+      "product_version": "1.4.7",
+      "capabilities": {
+        "connection.blocked": true,
+        "consumer_cancel_notify": true
+      }
+    },
+    "connected_at": 1476647837266
+  }
+]
+`
+
 func TestRabbitMQGeneratesMetrics(t *testing.T) {
 	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		var rsp string
@@ -385,6 +436,8 @@ func TestRabbitMQGeneratesMetrics(t *testing.T) {
 			rsp = sampleNodesResponse
 		case "/api/queues":
 			rsp = sampleQueuesResponse
+		case "/api/connections":
+			rsp = sampleConnectionsResponse
 		default:
 			panic("Cannot handle request")
 		}
@@ -441,4 +494,15 @@ func TestRabbitMQGeneratesMetrics(t *testing.T) {
 	}
 
 	assert.True(t, acc.HasMeasurement("rabbitmq_queue"))
+
+	assert.True(t, acc.HasMeasurement("rabbitmq_connection"))
+
+	connection_fields := map[string]interface{}{
+		"recv_cnt":  int64(124),
+		"send_cnt":  int64(7),
+		"send_pend": int64(0),
+		"state":     "running",
+	}
+
+	acc.AssertContainsFields(t, "rabbitmq_connection", connection_fields)
 }