Add go linter for workflow and repo. (Azure#62)

Add go linter for workflow and repo.

.github/workflows/ci-pipeline.yml

@@ -39,6 +39,12 @@ jobs:
         with:
           go-version: 1.15
 
+      - name: Check golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          # Optional: version of golangci-lint to use in form of v1.2 or v1.2.3 or `latest` to use the latest version
+          version: latest
+
       - name: Build project
         run: go build -v ./cmd/aks-periscope/aks-periscope.go
 

go.mod

@@ -5,7 +5,7 @@ go 1.15
 require (
 	github.com/Azure/azure-storage-blob-go v0.7.0
 	github.com/Azure/go-autorest/autorest/adal v0.9.13 // indirect
+	github.com/golangci/golangci-lint v1.40.1 // indirect
 	github.com/kr/pretty v0.2.1 // indirect
-	github.com/onsi/gomega v1.11.0
-	github.com/pkg/errors v0.8.1 // indirect
+	github.com/onsi/gomega v1.13.0
 )

pkg/collector/networkoutbound_collector.go

@@ -89,10 +89,10 @@ func (collector *NetworkOutboundCollector) Collect() error {
 		networkOutboundFile := filepath.Join(rootPath, outboundType.Type)
 
 		f, err := os.OpenFile(networkOutboundFile, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
-		defer f.Close()
 		if err != nil {
 			return fmt.Errorf("Fail to open file %s: %+v", networkOutboundFile, err)
 		}
+		defer f.Close()
 
 		timeout := time.Duration(5 * time.Second)
 		_, err = net.DialTimeout("tcp", outboundType.URL, timeout)

pkg/diagnoser/networkconfig_diagnoser.go

@@ -47,6 +47,9 @@ func NewNetworkConfigDiagnoser(dnsCollector *collector.DNSCollector, kubeletCmdC
 // Diagnose implements the interface method
 func (diagnoser *NetworkConfigDiagnoser) Diagnose() error {
 	hostName, err := utils.GetHostName()
+	if err != nil {
+		return err
+	}
 	rootPath, err := utils.CreateDiagnosticDir()
 	if err != nil {
 		return err
@@ -55,18 +58,18 @@ func (diagnoser *NetworkConfigDiagnoser) Diagnose() error {
 	networkDiagnosticFile := filepath.Join(rootPath, diagnoser.GetName())
 
 	f, err := os.OpenFile(networkDiagnosticFile, os.O_CREATE|os.O_WRONLY, 0644)
-	defer f.Close()
 	if err != nil {
 		return fmt.Errorf("Fail to open file %s: %+v", networkDiagnosticFile, err)
 	}
+	defer f.Close()
 
 	networkConfigDiagnosticData := networkConfigDiagnosticDatum{HostName: hostName}
 	for _, file := range diagnoser.dnsCollector.GetCollectorFiles() {
 		t, err := os.Open(file)
-		defer t.Close()
 		if err != nil {
 			return fmt.Errorf("Fail to open file %s: %+v", file, err)
 		}
+		defer t.Close()
 
 		dnsLevel := filepath.Base(file)
 		var dns []string

pkg/diagnoser/networkoutbound_diagnoser.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"encoding/json"
 	"fmt"
+	"log"
 	"os"
 	"path/filepath"
 	"time"
@@ -43,6 +44,9 @@ func NewNetworkOutboundDiagnoser(networkOutboundCollector *collector.NetworkOutb
 // Diagnose implements the interface method
 func (diagnoser *NetworkOutboundDiagnoser) Diagnose() error {
 	hostName, err := utils.GetHostName()
+	if err != nil {
+		return err
+	}
 	rootPath, err := utils.CreateDiagnosticDir()
 	if err != nil {
 		return err
@@ -51,25 +55,29 @@ func (diagnoser *NetworkOutboundDiagnoser) Diagnose() error {
 	networkOutboundDiagnosticFile := filepath.Join(rootPath, diagnoser.GetName())
 
 	f, err := os.OpenFile(networkOutboundDiagnosticFile, os.O_CREATE|os.O_WRONLY, 0644)
-	defer f.Close()
 	if err != nil {
 		return fmt.Errorf("Fail to open file %s: %+v", networkOutboundDiagnosticFile, err)
 	}
+	defer f.Close()
 
 	outboundDiagnosticData := []networkOutboundDiagnosticDatum{}
 
 	for _, file := range diagnoser.networkOutboundCollector.GetCollectorFiles() {
 		t, err := os.Open(file)
-		defer t.Close()
 		if err != nil {
 			return fmt.Errorf("Fail to open file %s: %+v", file, err)
 		}
+		defer t.Close()
 
 		dataPoint := networkOutboundDiagnosticDatum{HostName: hostName}
 		scanner := bufio.NewScanner(t)
 		for scanner.Scan() {
 			var outboundDatum collector.NetworkOutboundDatum
-			json.Unmarshal([]byte(scanner.Text()), &outboundDatum)
+			err := json.Unmarshal([]byte(scanner.Text()), &outboundDatum)
+			if err != nil {
+				log.Printf("Unmarshal failed: %+v", err)
+				continue
+			}
 
 			if dataPoint.Start.IsZero() {
 				setDataPoint(&outboundDatum, &dataPoint)

pkg/utils/helper.go

@@ -78,10 +78,10 @@ func RunCommandOnContainer(command string, arg ...string) (string, error) {
 // WriteToFile writes data to a file
 func WriteToFile(fileName string, data string) error {
 	f, err := os.Create(fileName)
-	defer f.Close()
 	if err != nil {
 		return fmt.Errorf("Fail to create file %s: %+v", fileName, err)
 	}
+	defer f.Close()
 
 	_, err = f.Write([]byte(data))
 	if err != nil {
@@ -206,7 +206,9 @@ func CreateCRD() error {
 
 	crdName := "aks-periscope-diagnostic" + "-" + hostName
 
-	writeDiagnosticCRD(crdName)
+	if err = writeDiagnosticCRD(crdName); err != nil {
+		return err
+	}
 
 	_, err = RunCommandOnContainer("kubectl", "apply", "-f", "aks-periscope-diagnostic-crd.yaml")
 	if err != nil {