Add struct tags for jti_openconfig_telemetry plugin

plugins/inputs/jti_openconfig_telemetry/README.md

@@ -42,6 +42,7 @@ This plugin reads Juniper Networks implementation of OpenConfig telemetry data f
   ]
 
   ## Optional TLS Config
+  # enable_tls = true
   # tls_ca = "/etc/telegraf/ca.pem"
   # tls_cert = "/etc/telegraf/cert.pem"
   # tls_key = "/etc/telegraf/key.pem"

plugins/inputs/jti_openconfig_telemetry/openconfig_telemetry.go

@@ -1,7 +1,6 @@
 package jti_openconfig_telemetry
 
 import (
-	"crypto/tls"
 	"fmt"
 	"log"
 	"net"
@@ -24,22 +23,19 @@ import (
 )
 
 type OpenConfigTelemetry struct {
-	Servers         []string
-	Sensors         []string
-	Username        string
-	Password        string
+	Servers         []string          `toml:"servers"`
+	Sensors         []string          `toml:"sensors"`
+	Username        string            `toml:"username"`
+	Password        string            `toml:"password"`
 	ClientID        string            `toml:"client_id"`
 	SampleFrequency internal.Duration `toml:"sample_frequency"`
 	StrAsTags       bool              `toml:"str_as_tags"`
 	RetryDelay      internal.Duration `toml:"retry_delay"`
-
-	sensorsConfig []sensorConfig
-
-	// GRPC settings
-	grpcClientConns []*grpc.ClientConn
 	EnableTLS       bool              `toml:"enable_tls"`
 	internaltls.ClientConfig
 
+	sensorsConfig   []sensorConfig
+	grpcClientConns []*grpc.ClientConn
 	wg              *sync.WaitGroup
 }
 
@@ -81,6 +77,7 @@ var (
   ]
 
   ## Optional TLS Config
+  # enable_tls = true
   # tls_ca = "/etc/telegraf/ca.pem"
   # tls_cert = "/etc/telegraf/cert.pem"
   # tls_key = "/etc/telegraf/key.pem"
@@ -353,23 +350,18 @@ func (m *OpenConfigTelemetry) collectData(ctx context.Context,
 
 func (m *OpenConfigTelemetry) Start(acc telegraf.Accumulator) error {
 
-	var tlscfg *tls.Config
-	var opts []grpc.DialOption
-	var err error
-
 	// Build sensors config
 	if m.splitSensorConfig() == 0 {
 		return fmt.Errorf("E! No valid sensor configuration available")
 	}
 
 	// Parse TLS config
+	var opts []grpc.DialOption
 	if m.EnableTLS {
-		if tlscfg, err = m.ClientConfig.TLSConfig(); err != nil {
+		tlscfg, err := m.ClientConfig.TLSConfig()
+		if err != nil {
 			return err
 		}
-	}
-
-	if tlscfg != nil {
 		opts = append(opts, grpc.WithTransportCredentials(credentials.NewTLS(tlscfg)))
 	} else {
 		opts = append(opts, grpc.WithInsecure())