Linter fixes for plugins/inputs/[fg]* (#9387)

plugins/inputs/fail2ban/fail2ban_test.go

@@ -103,29 +103,35 @@ func TestHelperProcess(_ *testing.T) {
 	if !strings.HasSuffix(cmd, "fail2ban-client") {
 		//nolint:errcheck,revive // Test will fail anyway
 		fmt.Fprint(os.Stdout, "command not found")
+		//nolint:revive // os.Exit called intentionally
 		os.Exit(1)
 	}
 
 	if len(args) == 1 && args[0] == "status" {
 		//nolint:errcheck,revive // Test will fail anyway
 		fmt.Fprint(os.Stdout, execStatusOutput)
+		//nolint:revive // os.Exit called intentionally
 		os.Exit(0)
 	} else if len(args) == 2 && args[0] == "status" {
 		if args[1] == "sshd" {
 			//nolint:errcheck,revive // Test will fail anyway
 			fmt.Fprint(os.Stdout, execStatusSshdOutput)
+			//nolint:revive // os.Exit called intentionally
 			os.Exit(0)
 		} else if args[1] == "postfix" {
 			//nolint:errcheck,revive // Test will fail anyway
 			fmt.Fprint(os.Stdout, execStatusPostfixOutput)
+			//nolint:revive // os.Exit called intentionally
 			os.Exit(0)
 		} else if args[1] == "dovecot" {
 			//nolint:errcheck,revive // Test will fail anyway
 			fmt.Fprint(os.Stdout, execStatusDovecotOutput)
+			//nolint:revive // os.Exit called intentionally
 			os.Exit(0)
 		}
 	}
 	//nolint:errcheck,revive // Test will fail anyway
 	fmt.Fprint(os.Stdout, "invalid argument")
+	//nolint:revive // os.Exit called intentionally
 	os.Exit(1)
 }

plugins/inputs/file/file_test.go

@@ -11,15 +11,18 @@ import (
 	"testing"
 	"time"
 
+	"github.com/stretchr/testify/require"
+
 	"github.com/influxdata/telegraf"
 	"github.com/influxdata/telegraf/plugins/parsers"
 	"github.com/influxdata/telegraf/plugins/parsers/csv"
 	"github.com/influxdata/telegraf/testutil"
-	"github.com/stretchr/testify/require"
 )
 
 func TestRefreshFilePaths(t *testing.T) {
 	wd, err := os.Getwd()
+	require.NoError(t, err)
+
 	r := File{
 		Files: []string{filepath.Join(wd, "dev/testfiles/**.log")},
 	}
@@ -100,7 +103,8 @@ func TestGrokParser(t *testing.T) {
 	require.NoError(t, err)
 
 	err = r.Gather(&acc)
-	require.Equal(t, len(acc.Metrics), 2)
+	require.NoError(t, err)
+	require.Len(t, acc.Metrics, 2)
 }
 
 func TestCharacterEncoding(t *testing.T) {

plugins/inputs/filecount/filesystem_helpers_test.go

@@ -53,11 +53,12 @@ func TestRealFS(t *testing.T) {
 	fs = getTestFileSystem()
 	// now, the same test as above will return an error as the file doesn't exist in our fake fs
 	expectedError := "Stat " + getTestdataDir() + "/qux: No such file or directory"
-	fileInfo, err = fs.Stat(getTestdataDir() + "/qux")
-	require.Equal(t, expectedError, err.Error())
+	_, err = fs.Stat(getTestdataDir() + "/qux")
+	require.Error(t, err, expectedError)
 	// and verify that what we DO expect to find, we do
 	fileInfo, err = fs.Stat("/testdata/foo")
 	require.NoError(t, err)
+	require.NotNil(t, fileInfo)
 }
 
 func getTestFileSystem() fakeFileSystem {

plugins/inputs/filestat/filestat.go

@@ -114,11 +114,11 @@ func (f *FileStat) Gather(acc telegraf.Accumulator) error {
 			}
 
 			if f.Md5 {
-				md5, err := getMd5(fileName)
+				md5Hash, err := getMd5(fileName)
 				if err != nil {
 					acc.AddError(err)
 				} else {
-					fields["md5_sum"] = md5
+					fields["md5_sum"] = md5Hash
 				}
 			}
 

plugins/inputs/filestat/filestat_test.go

@@ -198,7 +198,7 @@ func TestGetMd5(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, "5a7e9b77fa25e7bb411dbd17cf403c1f", md5)
 
-	md5, err = getMd5("/tmp/foo/bar/fooooo")
+	_, err = getMd5("/tmp/foo/bar/fooooo")
 	require.Error(t, err)
 }
 

plugins/inputs/fluentd/fluentd.go

@@ -63,11 +63,11 @@ func parse(data []byte) (datapointArray []pluginData, err error) {
 
 	if err = json.Unmarshal(data, &endpointData); err != nil {
 		err = fmt.Errorf("processing JSON structure")
-		return
+		return nil, err
 	}
 
 	datapointArray = append(datapointArray, endpointData.Payload...)
-	return
+	return datapointArray, err
 }
 
 // Description - display description

plugins/inputs/fluentd/fluentd_test.go

@@ -8,8 +8,9 @@ import (
 	"net/url"
 	"testing"
 
-	"github.com/influxdata/telegraf/testutil"
 	"github.com/stretchr/testify/require"
+
+	"github.com/influxdata/telegraf/testutil"
 )
 
 // sampleJSON from fluentd version '0.14.9'
@@ -127,6 +128,8 @@ func Test_Gather(t *testing.T) {
 	}))
 
 	requestURL, err := url.Parse(fluentdTest.Endpoint)
+	require.NoError(t, err)
+	require.NotNil(t, requestURL)
 
 	ts.Listener, _ = net.Listen("tcp", fmt.Sprintf("%s:%s", requestURL.Hostname(), requestURL.Port()))
 

plugins/inputs/github/github.go

@@ -8,12 +8,13 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/go-github/v32/github"
+	githubLib "github.com/google/go-github/v32/github"
+	"golang.org/x/oauth2"
+
 	"github.com/influxdata/telegraf"
 	"github.com/influxdata/telegraf/config"
 	"github.com/influxdata/telegraf/plugins/inputs"
 	"github.com/influxdata/telegraf/selfstat"
-	"golang.org/x/oauth2"
 )
 
 // GitHub - plugin main structure
@@ -23,7 +24,7 @@ type GitHub struct {
 	AdditionalFields  []string        `toml:"additional_fields"`
 	EnterpriseBaseURL string          `toml:"enterprise_base_url"`
 	HTTPTimeout       config.Duration `toml:"http_timeout"`
-	githubClient      *github.Client
+	githubClient      *githubLib.Client
 
 	obfuscatedToken string
 
@@ -68,7 +69,7 @@ func (g *GitHub) Description() string {
 }
 
 // Create GitHub Client
-func (g *GitHub) createGitHubClient(ctx context.Context) (*github.Client, error) {
+func (g *GitHub) createGitHubClient(ctx context.Context) (*githubLib.Client, error) {
 	httpClient := &http.Client{
 		Transport: &http.Transport{
 			Proxy: http.ProxyFromEnvironment,
@@ -93,11 +94,11 @@ func (g *GitHub) createGitHubClient(ctx context.Context) (*github.Client, error)
 	return g.newGithubClient(httpClient)
 }
 
-func (g *GitHub) newGithubClient(httpClient *http.Client) (*github.Client, error) {
+func (g *GitHub) newGithubClient(httpClient *http.Client) (*githubLib.Client, error) {
 	if g.EnterpriseBaseURL != "" {
-		return github.NewEnterpriseClient(g.EnterpriseBaseURL, "", httpClient)
+		return githubLib.NewEnterpriseClient(g.EnterpriseBaseURL, "", httpClient)
 	}
-	return github.NewClient(httpClient), nil
+	return githubLib.NewClient(httpClient), nil
 }
 
 // Gather GitHub Metrics
@@ -172,16 +173,16 @@ func (g *GitHub) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
-func (g *GitHub) handleRateLimit(response *github.Response, err error) {
+func (g *GitHub) handleRateLimit(response *githubLib.Response, err error) {
 	if err == nil {
 		g.RateLimit.Set(int64(response.Rate.Limit))
 		g.RateRemaining.Set(int64(response.Rate.Remaining))
-	} else if _, ok := err.(*github.RateLimitError); ok {
+	} else if _, ok := err.(*githubLib.RateLimitError); ok {
 		g.RateLimitErrors.Incr(1)
 	}
 }
 
-func splitRepositoryName(repositoryName string) (string, string, error) {
+func splitRepositoryName(repositoryName string) (owner string, repository string, err error) {
 	splits := strings.SplitN(repositoryName, "/", 2)
 
 	if len(splits) != 2 {
@@ -191,15 +192,15 @@ func splitRepositoryName(repositoryName string) (string, string, error) {
 	return splits[0], splits[1], nil
 }
 
-func getLicense(rI *github.Repository) string {
+func getLicense(rI *githubLib.Repository) string {
 	if licenseName := rI.GetLicense().GetName(); licenseName != "" {
 		return licenseName
 	}
 
 	return "None"
 }
 
-func getTags(repositoryInfo *github.Repository) map[string]string {
+func getTags(repositoryInfo *githubLib.Repository) map[string]string {
 	return map[string]string{
 		"owner":    repositoryInfo.GetOwner().GetLogin(),
 		"name":     repositoryInfo.GetName(),
@@ -208,7 +209,7 @@ func getTags(repositoryInfo *github.Repository) map[string]string {
 	}
 }
 
-func getFields(repositoryInfo *github.Repository) map[string]interface{} {
+func getFields(repositoryInfo *githubLib.Repository) map[string]interface{} {
 	return map[string]interface{}{
 		"stars":       repositoryInfo.GetStargazersCount(),
 		"subscribers": repositoryInfo.GetSubscribersCount(),
@@ -221,9 +222,9 @@ func getFields(repositoryInfo *github.Repository) map[string]interface{} {
 }
 
 func (g *GitHub) getPullRequestFields(ctx context.Context, owner, repo string) (map[string]interface{}, error) {
-	options := github.SearchOptions{
+	options := githubLib.SearchOptions{
 		TextMatch: false,
-		ListOptions: github.ListOptions{
+		ListOptions: githubLib.ListOptions{
 			PerPage: 100,
 			Page:    1,
 		},