Finally correctly configure TLS configuration for nsq input

plugins/inputs/nsq/nsq.go

@@ -23,9 +23,6 @@
 package nsq
 
 import (
-	"crypto/rand"
-	"crypto/tls"
-	"crypto/x509"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -36,30 +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
-	TlsCert        string
-	TlsKey         string
-	TlsCacert      string
-	httpClient     *http.Client
-	httpClientOnce *sync.Once
-	tlsConfig      *tls.Config
-	tlsConfigOnce  *sync.Once
+	Endpoints []string
+	tls.ClientConfig
+	httpClient *http.Client
 }
 
 var sampleConfig = `
   ## An array of NSQD HTTP API endpoints
   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_cacert = "/path/to/ca.pem"
+  endpoints            = ["https://localhost:4152"]
+  tls_cert             = "/path/to/client-cert.pem"
+  tls_key              = "/path/to/client-key.pem"
+  tls_cacert           = "/path/to/ca.pem"
+	insecure_skip_verify = false
 `
 
 const (
@@ -73,10 +67,7 @@ func init() {
 }
 
 func New() *NSQ {
-	return &NSQ{
-		httpClientOnce: &sync.Once{},
-		tlsConfigOnce:  &sync.Once{},
-	}
+	return &NSQ{}
 }
 
 func (n *NSQ) SampleConfig() string {
@@ -90,11 +81,11 @@ func (n *NSQ) Description() string {
 func (n *NSQ) Gather(acc telegraf.Accumulator) error {
 	var err error
 
-	n.tlsConfigOnce.Do(func() {
-		n.tlsConfig, err = n.buildTLSConfig()
-	})
-	if err != nil {
-		return fmt.Errorf("fail to build tls config: %v", err)
+	if n.httpClient == nil {
+		n.httpClient, err = n.getHttpClient()
+		if err != nil {
+			return err
+		}
 	}
 
 	var wg sync.WaitGroup
@@ -110,54 +101,27 @@ func (n *NSQ) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (n *NSQ) buildTLSConfig() (*tls.Config, error) {
-	if n.TlsCert == "" || n.TlsKey == "" || n.TlsCacert == "" {
-		return nil, nil
-	}
-
-	caCertBytes, err := ioutil.ReadFile(n.TlsCacert)
+func (n *NSQ) getHttpClient() (*http.Client, error) {
+	tlsConfig, err := n.ClientConfig.TLSConfig()
 	if err != nil {
-		return nil, fmt.Errorf("fail to read CA cert file %v: %v", n.TlsCacert, err)
+		return nil, err
 	}
-
-	cert, err := tls.LoadX509KeyPair(n.TlsCert, n.TlsKey)
-	if err != nil {
-		return nil, fmt.Errorf("fail to load certificate %v: %v", n.TlsCert, err)
+	tr := &http.Transport{
+		TLSClientConfig: tlsConfig,
 	}
-
-	pool := x509.NewCertPool()
-	pool.AppendCertsFromPEM(caCertBytes)
-
-	config := &tls.Config{
-		Certificates: []tls.Certificate{cert},
-		ClientCAs:    pool,
-		RootCAs:      pool,
+	httpClient := &http.Client{
+		Transport: tr,
+		Timeout:   time.Duration(4 * time.Second),
 	}
-
-	config.Rand = rand.Reader
-	return config, nil
-}
-
-func (n *NSQ) getHttpClient() *http.Client {
-	n.httpClientOnce.Do(func() {
-		tr := &http.Transport{
-			ResponseHeaderTimeout: time.Duration(3 * time.Second),
-			TLSClientConfig:       n.tlsConfig,
-		}
-		n.httpClient = &http.Client{
-			Transport: tr,
-			Timeout:   time.Duration(4 * time.Second),
-		}
-	})
-	return n.httpClient
+	return httpClient, nil
 }
 
 func (n *NSQ) gatherEndpoint(e string, acc telegraf.Accumulator) error {
 	u, err := buildURL(e)
 	if err != nil {
 		return err
 	}
-	r, err := n.getHttpClient().Get(u.String())
+	r, err := n.httpClient.Get(u.String())
 	if err != nil {
 		return fmt.Errorf("Error while polling %s: %s", u.String(), err)
 	}