Merge pull request #407 from doitintl/go-client-logger

feat: Disable any logging from go-client's klog

cmd/kubent/main.go

@@ -1,7 +1,9 @@
 package main
 
 import (
+	"flag"
 	"fmt"
+	"io"
 	"os"
 
 	"github.com/doitintl/kube-no-trouble/pkg/collector"
@@ -16,6 +18,7 @@ import (
 	_ "k8s.io/client-go/plugin/pkg/client/auth/azure"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/oidc"
+	"k8s.io/klog/v2"
 )
 
 var (
@@ -95,7 +98,7 @@ func getServerVersion(cv *judge.Version, collectors []collector.Collector) (*jud
 func main() {
 	exitCode := EXIT_CODE_FAIL_GENERIC
 
-	log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr})
+	configureGlobalLogging()
 
 	config, err := config.NewFromFlags()
 	if err != nil {
@@ -163,6 +166,17 @@ func main() {
 	os.Exit(exitCode)
 }
 
+func configureGlobalLogging() {
+	// disable any logging from K8S go-client
+	// unfortunately restConfig.WarningHandler does not handle auth plugins
+	klog.SetOutput(io.Discard)
+	flags := &flag.FlagSet{}
+	klog.InitFlags(flags)
+	flags.Set("logtostderr", "false")
+
+	log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr})
+}
+
 func outputResults(results []judge.Result, outputType string, outputFile string) error {
 	printer, err := printer.NewPrinter(outputType, outputFile)
 	if err != nil {

cmd/kubent/main_test.go

@@ -117,20 +117,22 @@ func TestMainExitCodes(t *testing.T) {
 		expected    int      // expected exit code
 		stdout      string   // expected stdout
 		outFileName string
+		emptyStderr bool
 	}{
-		{"success", []string{clusterFlagDisabled, helm3FlagDisabled}, 0, "", ""},
-		{"errorBadFlag", []string{"-c=not-boolean"}, 2, "", ""},
-		{"successFound", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, string(expectedJsonOutput), ""},
-		{"exitErrorFlagNone", []string{clusterFlagDisabled, helm3FlagDisabled, "-e"}, 0, "", ""},
-		{"exitErrorFlagFound", []string{clusterFlagDisabled, helm3FlagDisabled, "-e", "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 200, "", ""},
-		{"version short flag set", []string{"-v"}, 0, "", ""},
-		{"version long flag set", []string{"--version"}, 0, "", ""},
-		{"empty text output", []string{clusterFlagDisabled, helm3FlagDisabled}, 0, "", ""},
-		{"empty json output", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled}, 0, "[]\n", ""},
-		{"json-file", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, "", filepath.Join(tmpDir, "json-file.out")},
-		{"text-file", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, "", filepath.Join(tmpDir, "text-file.out")},
-		{"json-stdout", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, string(expectedJsonOutput), "-"},
-		{"error-bad-file", []string{clusterFlagDisabled, helm3FlagDisabled}, 1, "", "/this/dir/is/unlikely/to/exist"},
+		{"success", []string{clusterFlagDisabled, helm3FlagDisabled}, 0, "", "", false},
+		{"errorBadFlag", []string{"-c=not-boolean"}, 2, "", "", false},
+		{"successFound", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, string(expectedJsonOutput), "", false},
+		{"exitErrorFlagNone", []string{clusterFlagDisabled, helm3FlagDisabled, "-e"}, 0, "", "", false},
+		{"exitErrorFlagFound", []string{clusterFlagDisabled, helm3FlagDisabled, "-e", "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 200, "", "", false},
+		{"version short flag set", []string{"-v"}, 0, "", "", false},
+		{"version long flag set", []string{"--version"}, 0, "", "", false},
+		{"empty text output", []string{clusterFlagDisabled, helm3FlagDisabled}, 0, "", "", false},
+		{"empty json output", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled}, 0, "[]\n", "", false},
+		{"json-file", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, "", filepath.Join(tmpDir, "json-file.out"), false},
+		{"text-file", []string{"-o=text", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, "", filepath.Join(tmpDir, "text-file.out"), false},
+		{"json-stdout", []string{"-o=json", clusterFlagDisabled, helm3FlagDisabled, "-f=" + filepath.Join(FIXTURES_DIR, "deployment-v1beta1.yaml")}, 0, string(expectedJsonOutput), "-", false},
+		{"error-bad-file", []string{clusterFlagDisabled, helm3FlagDisabled}, 1, "", "/this/dir/is/unlikely/to/exist", false},
+		{"no-3rdparty-output", []string{clusterFlagDisabled, helm3FlagDisabled, "-l=disabled"}, 0, "", "", true},
 	}
 
 	if os.Getenv("TEST_EXIT_CODE") == "1" {
@@ -150,11 +152,18 @@ func TestMainExitCodes(t *testing.T) {
 			}
 			base64Args, _ := encodeBase64(tc.args)
 
+			var stdout, stderr bytes.Buffer
+
 			cmd := exec.Command(os.Args[0], "-test.run=TestMainExitCodes")
 			cmd.Env = append(os.Environ(),
 				"TEST_EXIT_CODE=1",
 				"TEST_ARGS="+base64Args)
-			out, err := cmd.Output()
+			cmd.Stdout = &stdout
+			cmd.Stderr = &stderr
+			err := cmd.Run()
+
+			outStr := stdout.String()
+			errStr := stderr.String()
 
 			if tc.expected == 0 && err != nil {
 				t.Fatalf("expected to succeed with exit code %d, failed with %v", tc.expected, err)
@@ -171,16 +180,19 @@ func TestMainExitCodes(t *testing.T) {
 					t.Fatalf("expected to get exit code %d, failed with %v", tc.expected, err)
 				}
 			}
-			if tc.expected == 0 && err == nil && tc.stdout != string(out) {
-				t.Fatalf("expected to get stdout as %s, instead got %s", tc.stdout, out)
+			if tc.expected == 0 && err == nil && tc.stdout != outStr {
+				t.Fatalf("expected to get stdout as %s, instead got %s", tc.stdout, outStr)
 			}
 
 			if tc.expected == 0 && err == nil && tc.outFileName != "" && tc.outFileName != "-" {
 				if fs, err := os.Stat(tc.outFileName); err != nil || fs.Size() == 0 {
-					t.Fatalf("expected non-empty outputdile: %s, got error: %v", tc.outFileName, err)
+					t.Fatalf("expected non-empty outputfile: %s, got error: %v", tc.outFileName, err)
 				}
 			}
 
+			if tc.emptyStderr && errStr != "" {
+				t.Fatalf("expected empty stderr, got: %s", errStr)
+			}
 		})
 	}
 }
@@ -282,3 +294,9 @@ func Test_outputResults(t *testing.T) {
 		})
 	}
 }
+
+func Test_configureGlobalLogging(t *testing.T) {
+	// just make sure the method runs, this is mostly covered
+	//by the Test_MainExitCodes
+	configureGlobalLogging()
+}

go.mod

@@ -6,11 +6,12 @@ require (
 	github.com/ghodss/yaml v1.0.0
 	github.com/hashicorp/go-version v1.3.0
 	github.com/open-policy-agent/opa v0.46.1
-	github.com/rs/zerolog v1.21.1-0.20210413053206-582f0cf0e39b
+	github.com/rs/zerolog v1.26.1
 	github.com/spf13/pflag v1.0.5
 	helm.sh/helm/v3 v3.10.2
 	k8s.io/apimachinery v0.25.4
 	k8s.io/client-go v0.25.4
+	k8s.io/klog/v2 v2.70.1
 )
 
 require (
@@ -77,7 +78,6 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/api v0.25.4 // indirect
 	k8s.io/apiextensions-apiserver v0.25.2 // indirect
-	k8s.io/klog/v2 v2.70.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20220803162953-67bda5d908f1 // indirect
 	k8s.io/utils v0.0.0-20220728103510-ee6ede2d64ed // indirect
 	sigs.k8s.io/json v0.0.0-20220713155537-f223a00ba0e2 // indirect

go.sum

@@ -104,7 +104,6 @@ github.com/cncf/udpa/go v0.0.0-20200629203442-efcf912fb354/go.mod h1:WmhPx2Nbnht
 github.com/cncf/udpa/go v0.0.0-20201120205902-5459f2c99403/go.mod h1:WmhPx2Nbnhtbo57+VJT5O0JRkEi1Wbu0z5j0R8u5Hbk=
 github.com/cncf/xds/go v0.0.0-20210312221358-fbca930ec8ed/go.mod h1:eXthEFrGJvWHgFFCl3hGmgk+/aYT6PnTQLykKQRLhEs=
 github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
-github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/go-systemd/v22 v22.3.2/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
 github.com/cpuguy83/go-md2man/v2 v2.0.0/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
@@ -393,9 +392,9 @@ github.com/rcrowley/go-metrics v0.0.0-20200313005456-10cdbea86bc0/go.mod h1:bCqn
 github.com/rogpeppe/fastuuid v1.2.0/go.mod h1:jVj6XXZzXRy/MSR5jhDC/2q6DgLz+nrA6LYCDYWNEvQ=
 github.com/rogpeppe/go-internal v1.3.0/go.mod h1:M8bDsm7K2OlrFYOpmOWEs/qY81heoFRclV5y23lUDJ4=
 github.com/rogpeppe/go-internal v1.8.0/go.mod h1:WmiCO8CzOY8rg0OYDC4/i/2WRWAB6poM+XZ2dLUbcbE=
-github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
-github.com/rs/zerolog v1.21.1-0.20210413053206-582f0cf0e39b h1:lZjlZ6/ExLhIqPOmlh0dVJnBbiKokcjffr022PlkSSo=
-github.com/rs/zerolog v1.21.1-0.20210413053206-582f0cf0e39b/go.mod h1:ZPhntP/xmq1nnND05hhpAh2QMhSsA4UN3MGZ6O2J3hM=
+github.com/rs/xid v1.3.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
+github.com/rs/zerolog v1.26.1 h1:/ihwxqH+4z8UxyI70wM1z9yCvkWcfz/a3mj48k/Zngc=
+github.com/rs/zerolog v1.26.1/go.mod h1:/wSSJWX7lVrsOwlbyTRSOJvqRlc+WjWlfes+CiJ+tmc=
 github.com/rubenv/sql-migrate v1.1.2 h1:9M6oj4e//owVVHYrFISmY9LBRw6gzkCNmD9MV36tZeQ=
 github.com/rubenv/sql-migrate v1.1.2/go.mod h1:/7TZymwxN8VWumcIxw1jjHEcR1djpdkMHQPT4FWdnbQ=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
@@ -470,6 +469,7 @@ golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20200820211705-5c72a883971a/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
 golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/crypto v0.0.0-20211215153901-e495a2d5b3d3/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
+golang.org/x/crypto v0.0.0-20211215165025-cf75a172585e/go.mod h1:P+XmwS30IXTQdn5tA2iutPOUgjI07+tq3H3K9MVA1s8=
 golang.org/x/crypto v0.0.0-20220525230936-793ad666bf5e h1:T8NU3HyQ8ClP4SEE+KbFlg6n0NhuTsN4MyznaarGsZM=
 golang.org/x/crypto v0.0.0-20220525230936-793ad666bf5e/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=

pkg/collector/kube.go

@@ -38,6 +38,7 @@ func newClientRestConfig(kubeconfig string, kubecontext string, inClusterFn func
 	if kubeconfig == "" {
 		if restConfig, err := inClusterFn(); err == nil {
 			restConfig.UserAgent = userAgent
+			restConfig.WarningHandler = rest.NoWarnings{}
 			return restConfig, nil
 		}
 	}
@@ -64,6 +65,7 @@ func newClientRestConfig(kubeconfig string, kubecontext string, inClusterFn func
 	}
 
 	restConfig.UserAgent = userAgent
+	restConfig.WarningHandler = rest.NoWarnings{}
 	return restConfig, nil
 }
 

pkg/collector/kube_test.go

@@ -3,6 +3,7 @@ package collector
 import (
 	"os"
 	"path/filepath"
+	"reflect"
 	"testing"
 
 	"k8s.io/client-go/rest"
@@ -141,6 +142,14 @@ func TestNewClientRestConfigWithContext(t *testing.T) {
 	if config.Host != expectedHost {
 		t.Fatalf("Expected host from context %s to be: %s, got %s instead", expectedContext, expectedHost, config.Host)
 	}
+
+	if config.UserAgent != USER_AGENT {
+		t.Fatalf("Expected %s UserAgent, instead got: %s", USER_AGENT, config.UserAgent)
+	}
+
+	if _, ok := config.WarningHandler.(rest.NoWarnings); !ok {
+		t.Fatalf("Expected NoWarnings warnings handler, instead got: %s", reflect.TypeOf(config.WarningHandler).Name())
+	}
 }
 
 func TestNewClientRestConfigContextMissing(t *testing.T) {
@@ -165,6 +174,12 @@ func TestNewClientRestConfigInCluster(t *testing.T) {
 	if cfg.Host != expectedHost {
 		t.Fatalf("Expected %s host, instead got: %s", expectedHost, cfg.Host)
 	}
+	if cfg.UserAgent != USER_AGENT {
+		t.Fatalf("Expected %s UserAgent, instead got: %s", USER_AGENT, cfg.UserAgent)
+	}
+	if _, ok := cfg.WarningHandler.(rest.NoWarnings); !ok {
+		t.Fatalf("Expected NoWarnings warnings handler, instead got: %s", reflect.TypeOf(cfg.WarningHandler).Name())
+	}
 }
 
 type env struct {