Merge pull request #26696 from gitfred/no-header-custom-column

Automatic merge from submit-queue

--no-header available now for custom-column

Change `CustomColumnsPrinter` to have `noHeader` boolean, also changed `GetPrinter` to receive this bool and pass it through.
One test `TestNewColumnPrinterFromSpecWithNoHeaders` added for checking if there is no headers in output for sure

fixes #24133

pkg/kubectl/cmd/clusterinfo_dump.go

@@ -91,7 +91,7 @@ func dumpClusterInfo(f *cmdutil.Factory, cmd *cobra.Command, args []string, out
 	if c, err = f.Client(); err != nil {
 		return err
 	}
-	printer, _, err := kubectl.GetPrinter("json", "")
+	printer, _, err := kubectl.GetPrinter("json", "", false)
 	if err != nil {
 		return err
 	}

pkg/kubectl/cmd/convert.go

@@ -150,7 +150,7 @@ func (o *ConvertOptions) Complete(f *cmdutil.Factory, out io.Writer, cmd *cobra.
 		}
 	}
 	o.encoder = f.JSONEncoder()
-	o.printer, _, err = kubectl.GetPrinter(outputFormat, templateFile)
+	o.printer, _, err = kubectl.GetPrinter(outputFormat, templateFile, false)
 	if err != nil {
 		return err
 	}

pkg/kubectl/cmd/util/printing.go

@@ -52,7 +52,7 @@ func AddOutputFlags(cmd *cobra.Command) {
 
 // AddNoHeadersFlags adds no-headers flags to a command.
 func AddNoHeadersFlags(cmd *cobra.Command) {
-	cmd.Flags().Bool("no-headers", false, "When using the default output, don't print headers.")
+	cmd.Flags().Bool("no-headers", false, "When using the default or custom-column output format, don't print headers.")
 }
 
 // PrintSuccess prints message after finishing mutating operations
@@ -121,7 +121,7 @@ func PrinterForCommand(cmd *cobra.Command) (kubectl.ResourcePrinter, bool, error
 		}
 	}
 
-	printer, generic, err := kubectl.GetPrinter(outputFormat, templateFile)
+	printer, generic, err := kubectl.GetPrinter(outputFormat, templateFile, GetFlagBool(cmd, "no-headers"))
 	if err != nil {
 		return nil, generic, err
 	}

pkg/kubectl/custom_column_printer.go

@@ -73,7 +73,7 @@ func massageJSONPath(pathExpression string) (string, error) {
 //
 //      NAME               API_VERSION
 //      foo                bar
-func NewCustomColumnsPrinterFromSpec(spec string, decoder runtime.Decoder) (*CustomColumnsPrinter, error) {
+func NewCustomColumnsPrinterFromSpec(spec string, decoder runtime.Decoder, noHeaders bool) (*CustomColumnsPrinter, error) {
 	if len(spec) == 0 {
 		return nil, fmt.Errorf("custom-columns format specified but no custom columns given")
 	}
@@ -90,7 +90,7 @@ func NewCustomColumnsPrinterFromSpec(spec string, decoder runtime.Decoder) (*Cus
 		}
 		columns[ix] = Column{Header: colSpec[0], FieldSpec: spec}
 	}
-	return &CustomColumnsPrinter{Columns: columns, Decoder: decoder}, nil
+	return &CustomColumnsPrinter{Columns: columns, Decoder: decoder, NoHeaders: noHeaders}, nil
 }
 
 func splitOnWhitespace(line string) []string {
@@ -135,7 +135,7 @@ func NewCustomColumnsPrinterFromTemplate(templateReader io.Reader, decoder runti
 			FieldSpec: spec,
 		}
 	}
-	return &CustomColumnsPrinter{Columns: columns, Decoder: decoder}, nil
+	return &CustomColumnsPrinter{Columns: columns, Decoder: decoder, NoHeaders: false}, nil
 }
 
 // Column represents a user specified column
@@ -152,15 +152,19 @@ type Column struct {
 type CustomColumnsPrinter struct {
 	Columns   []Column
 	Decoder   runtime.Decoder
+	NoHeaders bool
 }
 
 func (s *CustomColumnsPrinter) PrintObj(obj runtime.Object, out io.Writer) error {
 	w := tabwriter.NewWriter(out, columnwidth, tabwidth, padding, padding_character, flags)
+
+	if !s.NoHeaders {
 		headers := make([]string, len(s.Columns))
 		for ix := range s.Columns {
 			headers[ix] = s.Columns[ix].Header
 		}
 		fmt.Fprintln(w, strings.Join(headers, "\t"))
+	}
 	parsers := make([]*jsonpath.JSONPath, len(s.Columns))
 	for ix := range s.Columns {
 		parsers[ix] = jsonpath.New(fmt.Sprintf("column%d", ix))

pkg/kubectl/custom_column_printer_test.go

@@ -19,6 +19,7 @@ package kubectl
 import (
 	"bytes"
 	"reflect"
+	"strings"
 	"testing"
 
 	"k8s.io/kubernetes/pkg/api"
@@ -67,6 +68,7 @@ func TestNewColumnPrinterFromSpec(t *testing.T) {
 		expectedColumns []Column
 		expectErr       bool
 		name            string
+		noHeaders       bool
 	}{
 		{
 			spec:      "",
@@ -102,9 +104,14 @@ func TestNewColumnPrinterFromSpec(t *testing.T) {
 				},
 			},
 		},
+		{
+			spec:      "API_VERSION:apiVersion",
+			name:      "no-headers",
+			noHeaders: true,
+		},
 	}
 	for _, test := range tests {
-		printer, err := NewCustomColumnsPrinterFromSpec(test.spec, api.Codecs.UniversalDecoder())
+		printer, err := NewCustomColumnsPrinterFromSpec(test.spec, api.Codecs.UniversalDecoder(), test.noHeaders)
 		if test.expectErr {
 			if err == nil {
 				t.Errorf("[%s] unexpected non-error", test.name)
@@ -115,8 +122,19 @@ func TestNewColumnPrinterFromSpec(t *testing.T) {
 			t.Errorf("[%s] unexpected error: %v", test.name, err)
 			continue
 		}
+		if test.noHeaders {
+			buffer := &bytes.Buffer{}
 
-		if !reflect.DeepEqual(test.expectedColumns, printer.Columns) {
+			printer.PrintObj(&api.Pod{}, buffer)
+			if err != nil {
+				t.Fatalf("An error occurred printing Pod: %#v", err)
+			}
+
+			if contains(strings.Fields(buffer.String()), "API_VERSION") {
+				t.Errorf("unexpected header API_VERSION")
+			}
+
+		} else if !reflect.DeepEqual(test.expectedColumns, printer.Columns) {
 			t.Errorf("[%s]\nexpected:\n%v\nsaw:\n%v\n", test.name, test.expectedColumns, printer.Columns)
 		}
 

pkg/kubectl/resource_printer.go

@@ -62,7 +62,7 @@ const (
 // is agnostic to schema versions, so you must send arguments to PrintObj in the
 // version you wish them to be shown using a VersionedPrinter (typically when
 // generic is true).
-func GetPrinter(format, formatArgument string) (ResourcePrinter, bool, error) {
+func GetPrinter(format, formatArgument string, noHeaders bool) (ResourcePrinter, bool, error) {
 	var printer ResourcePrinter
 	switch format {
 	case "json":
@@ -119,7 +119,7 @@ func GetPrinter(format, formatArgument string) (ResourcePrinter, bool, error) {
 		}
 	case "custom-columns":
 		var err error
-		if printer, err = NewCustomColumnsPrinterFromSpec(formatArgument, api.Codecs.UniversalDecoder()); err != nil {
+		if printer, err = NewCustomColumnsPrinterFromSpec(formatArgument, api.Codecs.UniversalDecoder(), noHeaders); err != nil {
 			return nil, false, err
 		}
 	case "custom-columns-file":

pkg/kubectl/resource_printer_test.go

@@ -75,7 +75,7 @@ func TestVersionedPrinter(t *testing.T) {
 }
 
 func TestPrintDefault(t *testing.T) {
-	printer, found, err := GetPrinter("", "")
+	printer, found, err := GetPrinter("", "", false)
 	if err != nil {
 		t.Fatalf("unexpected error: %#v", err)
 	}
@@ -129,7 +129,7 @@ func TestPrinter(t *testing.T) {
 	}
 	for _, test := range printerTests {
 		buf := bytes.NewBuffer([]byte{})
-		printer, found, err := GetPrinter(test.Format, test.FormatArgument)
+		printer, found, err := GetPrinter(test.Format, test.FormatArgument, false)
 		if err != nil || !found {
 			t.Errorf("in %s, unexpected error: %#v", test.Name, err)
 		}
@@ -156,7 +156,7 @@ func TestBadPrinter(t *testing.T) {
 		{"bad jsonpath", "jsonpath", "{.Name", fmt.Errorf("error parsing jsonpath {.Name, unclosed action\n")},
 	}
 	for _, test := range badPrinterTests {
-		_, _, err := GetPrinter(test.Format, test.FormatArgument)
+		_, _, err := GetPrinter(test.Format, test.FormatArgument, false)
 		if err == nil || err.Error() != test.Error.Error() {
 			t.Errorf("in %s, expect %s, got %s", test.Name, test.Error, err)
 		}
@@ -333,7 +333,7 @@ func TestNamePrinter(t *testing.T) {
 			},
 			"pod/foo\npod/bar\n"},
 	}
-	printer, _, _ := GetPrinter("name", "")
+	printer, _, _ := GetPrinter("name", "", false)
 	for name, item := range tests {
 		buff := &bytes.Buffer{}
 		err := printer.PrintObj(item.obj, buff)