Change hddtemp to always put temperature in temperature field (#1905)

Added unit tests for the changes

Fixes #1904

plugins/inputs/hddtemp/go-hddtemp/hddtemp.go

@@ -8,7 +8,7 @@ import (
 	"strings"
 )
 
-type disk struct {
+type Disk struct {
 	DeviceName  string
 	Model       string
 	Temperature int32
@@ -16,12 +16,19 @@ type disk struct {
 	Status      string
 }
 
-func Fetch(address string) ([]disk, error) {
+type hddtemp struct {
+}
+
+func New() *hddtemp {
+	return &hddtemp{}
+}
+
+func (h *hddtemp) Fetch(address string) ([]Disk, error) {
 	var (
 		err    error
 		conn   net.Conn
 		buffer bytes.Buffer
-		disks  []disk
+		disks  []Disk
 	)
 
 	if conn, err = net.Dial("tcp", address); err != nil {
@@ -48,7 +55,7 @@ func Fetch(address string) ([]disk, error) {
 			status = temperatureField
 		}
 
-		disks = append(disks, disk{
+		disks = append(disks, Disk{
 			DeviceName:  device,
 			Model:       fields[offset+2],
 			Temperature: int32(temperature),

plugins/inputs/hddtemp/go-hddtemp/hddtemp_test.go

@@ -10,13 +10,13 @@ func TestFetch(t *testing.T) {
 	l := serve(t, []byte("|/dev/sda|foobar|36|C|"))
 	defer l.Close()
 
-	disks, err := Fetch(l.Addr().String())
+	disks, err := New().Fetch(l.Addr().String())
 
 	if err != nil {
 		t.Error("expecting err to be nil")
 	}
 
-	expected := []disk{
+	expected := []Disk{
 		{
 			DeviceName:  "sda",
 			Model:       "foobar",
@@ -31,7 +31,7 @@ func TestFetch(t *testing.T) {
 }
 
 func TestFetchWrongAddress(t *testing.T) {
-	_, err := Fetch("127.0.0.1:1")
+	_, err := New().Fetch("127.0.0.1:1")
 
 	if err == nil {
 		t.Error("expecting err to be non-nil")
@@ -42,13 +42,13 @@ func TestFetchStatus(t *testing.T) {
 	l := serve(t, []byte("|/dev/sda|foobar|SLP|C|"))
 	defer l.Close()
 
-	disks, err := Fetch(l.Addr().String())
+	disks, err := New().Fetch(l.Addr().String())
 
 	if err != nil {
 		t.Error("expecting err to be nil")
 	}
 
-	expected := []disk{
+	expected := []Disk{
 		{
 			DeviceName:  "sda",
 			Model:       "foobar",
@@ -67,13 +67,13 @@ func TestFetchTwoDisks(t *testing.T) {
 	l := serve(t, []byte("|/dev/hda|ST380011A|46|C||/dev/hdd|ST340016A|SLP|*|"))
 	defer l.Close()
 
-	disks, err := Fetch(l.Addr().String())
+	disks, err := New().Fetch(l.Addr().String())
 
 	if err != nil {
 		t.Error("expecting err to be nil")
 	}
 
-	expected := []disk{
+	expected := []Disk{
 		{
 			DeviceName:  "hda",
 			Model:       "ST380011A",