Add support for TLS configuration in NSQ input (influxdata#3903)

plugins/inputs/nsq/nsq.go

@@ -33,17 +33,27 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/tls"
 	"github.com/influxdata/telegraf/plugins/inputs"
 )
 
 // Might add Lookupd endpoints for cluster discovery
 type NSQ struct {
 	Endpoints []string
+	tls.ClientConfig
+	httpClient *http.Client
 }
 
 var sampleConfig = `
   ## An array of NSQD HTTP API endpoints
-  endpoints = ["http://localhost:4151"]
+  endpoints  = ["http://localhost:4151"]
+
+  ## Or using HTTPS endpoint
+  endpoints            = ["https://localhost:4152"]
+  tls_cert             = "/path/to/client-cert.pem"
+  tls_key              = "/path/to/client-key.pem"
+  tls_ca               = "/path/to/ca.pem"
+  insecure_skip_verify = false
 `
 
 const (
@@ -52,10 +62,14 @@ const (
 
 func init() {
 	inputs.Add("nsq", func() telegraf.Input {
-		return &NSQ{}
+		return New()
 	})
 }
 
+func New() *NSQ {
+	return &NSQ{}
+}
+
 func (n *NSQ) SampleConfig() string {
 	return sampleConfig
 }
@@ -65,6 +79,15 @@ func (n *NSQ) Description() string {
 }
 
 func (n *NSQ) Gather(acc telegraf.Accumulator) error {
+	var err error
+
+	if n.httpClient == nil {
+		n.httpClient, err = n.getHttpClient()
+		if err != nil {
+			return err
+		}
+	}
+
 	var wg sync.WaitGroup
 	for _, e := range n.Endpoints {
 		wg.Add(1)
@@ -78,21 +101,27 @@ func (n *NSQ) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-var tr = &http.Transport{
-	ResponseHeaderTimeout: time.Duration(3 * time.Second),
-}
-
-var client = &http.Client{
-	Transport: tr,
-	Timeout:   time.Duration(4 * time.Second),
+func (n *NSQ) getHttpClient() (*http.Client, error) {
+	tlsConfig, err := n.ClientConfig.TLSConfig()
+	if err != nil {
+		return nil, err
+	}
+	tr := &http.Transport{
+		TLSClientConfig: tlsConfig,
+	}
+	httpClient := &http.Client{
+		Transport: tr,
+		Timeout:   time.Duration(4 * time.Second),
+	}
+	return httpClient, nil
 }
 
 func (n *NSQ) gatherEndpoint(e string, acc telegraf.Accumulator) error {
 	u, err := buildURL(e)
 	if err != nil {
 		return err
 	}
-	r, err := client.Get(u.String())
+	r, err := n.httpClient.Get(u.String())
 	if err != nil {
 		return fmt.Errorf("Error while polling %s: %s", u.String(), err)
 	}

plugins/inputs/nsq/nsq_test.go

@@ -19,9 +19,8 @@ func TestNSQStatsV1(t *testing.T) {
 	}))
 	defer ts.Close()
 
-	n := &NSQ{
-		Endpoints: []string{ts.URL},
-	}
+	n := New()
+	n.Endpoints = []string{ts.URL}
 
 	var acc testutil.Accumulator
 	err := acc.GatherError(n.Gather)
@@ -276,9 +275,8 @@ func TestNSQStatsPreV1(t *testing.T) {
 	}))
 	defer ts.Close()
 
-	n := &NSQ{
-		Endpoints: []string{ts.URL},
-	}
+	n := New()
+	n.Endpoints = []string{ts.URL}
 
 	var acc testutil.Accumulator
 	err := acc.GatherError(n.Gather)