jsonpath user guide docs

pkg/kubectl/cmd/get.go

@@ -69,7 +69,7 @@ func NewCmdGet(f *cmdutil.Factory, out io.Writer) *cobra.Command {
 	validArgs := p.HandledResources()
 
 	cmd := &cobra.Command{
-		Use:     "get [(-o|--output=)json|yaml|template|templatefile|wide|jsonpath|...] (TYPE [NAME | -l label] | TYPE/NAME ...)",
+		Use:     "get [(-o|--output=)json|yaml|template|templatefile|wide|jsonpath|...] (TYPE [NAME | -l label] | TYPE/NAME ...) [flags]",
 		Short:   "Display one or many resources",
 		Long:    get_long,
 		Example: get_example,

pkg/kubectl/cmd/util/printing.go

@@ -31,7 +31,7 @@ func AddPrinterFlags(cmd *cobra.Command) {
 	cmd.Flags().StringP("output", "o", "", "Output format. One of: json|yaml|template|templatefile|wide|jsonpath.")
 	cmd.Flags().String("output-version", "", "Output the formatted object with the given version (default api-version).")
 	cmd.Flags().Bool("no-headers", false, "When using the default output, don't print headers.")
-	cmd.Flags().StringP("template", "t", "", "Template string or path to template file to use when -o=template, -o=templatefile or -o=jsonpath.  The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview]. The jsonpath template is composed of jsonpath expressions enclosed by {}")
+	cmd.Flags().StringP("template", "t", "", "Template string or path to template file to use when -o=template, -o=templatefile or -o=jsonpath.  The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview]. The jsonpath template is composed of jsonpath expressions enclosed by {} [http://releases.k8s.io/HEAD/docs/user-guide/jsonpath.md]")
 	cmd.Flags().String("sort-by", "", "If non-empty, sort list types using this field specification.  The field specification is expressed as a JSONPath expression (e.g. 'ObjectMeta.Name'). The field in the API resource specified by this JSONPath expression must be an integer or a string.")
 	cmd.Flags().BoolP("show-all", "a", false, "When printing, show all resources (default hide terminated pods.)")
 }

pkg/kubectl/resource_printer_test.go

@@ -77,14 +77,6 @@ func TestVersionedPrinter(t *testing.T) {
 	}
 }
 
-func TestYAMLPrinter(t *testing.T) {
-	testPrinter(t, &YAMLPrinter{}, yaml.Unmarshal)
-}
-
-func TestJSONPrinter(t *testing.T) {
-	testPrinter(t, &JSONPrinter{}, json.Unmarshal)
-}
-
 func TestPrintDefault(t *testing.T) {
 	printer, found, err := GetPrinter("", "")
 	if err != nil {
@@ -95,107 +87,72 @@ func TestPrintDefault(t *testing.T) {
 	}
 }
 
-type internalType struct {
-	Name string
+type TestPrintType struct {
+	Data string
 }
 
-func (*internalType) IsAnAPIObject() {
+func (*TestPrintType) IsAnAPIObject() {}
 
-}
+type TestUnknownType struct{}
 
-func TestPrintJSONForObject(t *testing.T) {
-	buf := bytes.NewBuffer([]byte{})
-	printer, found, err := GetPrinter("json", "")
-	if err != nil || !found {
-		t.Fatalf("unexpected error: %#v", err)
-	}
-	if err := printer.PrintObj(&internalType{Name: "foo"}, buf); err != nil {
-		t.Fatalf("unexpected error: %#v", err)
-	}
-	obj := map[string]interface{}{}
-	if err := json.Unmarshal(buf.Bytes(), &obj); err != nil {
-		t.Fatalf("unexpected error: %#v\n%s", err, buf.String())
-	}
-	if obj["Name"] != "foo" {
-		t.Errorf("unexpected field: %#v", obj)
-	}
-}
+func (*TestUnknownType) IsAnAPIObject() {}
 
-func TestPrintJSON(t *testing.T) {
-	buf := bytes.NewBuffer([]byte{})
-	printer, found, err := GetPrinter("json", "")
-	if err != nil || !found {
-		t.Fatalf("unexpected error: %#v", err)
-	}
-	printer.PrintObj(&api.Pod{ObjectMeta: api.ObjectMeta{Name: "foo"}}, buf)
-	obj := map[string]interface{}{}
-	if err := json.Unmarshal(buf.Bytes(), &obj); err != nil {
-		t.Errorf("unexpected error: %#v\n%s", err, buf.String())
-	}
-}
-
-func TestPrintYAML(t *testing.T) {
-	buf := bytes.NewBuffer([]byte{})
-	printer, found, err := GetPrinter("yaml", "")
-	if err != nil || !found {
-		t.Fatalf("unexpected error: %#v", err)
-	}
-	printer.PrintObj(&api.Pod{ObjectMeta: api.ObjectMeta{Name: "foo"}}, buf)
-	obj := map[string]interface{}{}
-	if err := yaml.Unmarshal(buf.Bytes(), &obj); err != nil {
-		t.Errorf("unexpected error: %#v\n%s", err, buf.String())
-	}
-}
-
-func TestPrintTemplate(t *testing.T) {
-	buf := bytes.NewBuffer([]byte{})
-	printer, found, err := GetPrinter("template", "{{if .id}}{{.id}}{{end}}{{if .metadata.name}}{{.metadata.name}}{{end}}")
-	if err != nil || !found {
-		t.Fatalf("unexpected error: %#v", err)
-	}
-	unversionedPod := &api.Pod{ObjectMeta: api.ObjectMeta{Name: "foo"}}
-	obj, err := api.Scheme.ConvertToVersion(unversionedPod, testapi.Version())
-	err = printer.PrintObj(obj, buf)
+func TestPrinter(t *testing.T) {
+	//test inputs
+	simpleTest := &TestPrintType{"foo"}
+	podTest := &api.Pod{ObjectMeta: api.ObjectMeta{Name: "foo"}}
+	testapi, err := api.Scheme.ConvertToVersion(podTest, testapi.Version())
 	if err != nil {
-		t.Fatalf("unexpected error: %#v", err)
+		t.Fatalf("unexpected error: %v", err)
 	}
-	if buf.String() != "foo" {
-		t.Errorf("unexpected output: %s", buf.String())
+
+	printerTests := []struct {
+		Name           string
+		Format         string
+		FormatArgument string
+		Input          runtime.Object
+		Expect         string
+	}{
+		{"test json", "json", "", simpleTest, "{\n    \"Data\": \"foo\"\n}\n"},
+		{"test yaml", "yaml", "", simpleTest, "Data: foo\n"},
+		{"test template", "template", "{{if .id}}{{.id}}{{end}}{{if .metadata.name}}{{.metadata.name}}{{end}}",
+			podTest, "foo"},
+		{"test jsonpath", "jsonpath", "{.metadata.name}", podTest, "foo"},
+		{"emits versioned objects", "template", "{{.kind}}", testapi, "Pod"},
 	}
+	for _, test := range printerTests {
+		buf := bytes.NewBuffer([]byte{})
+		printer, found, err := GetPrinter(test.Format, test.FormatArgument)
+		if err != nil || !found {
+			t.Errorf("unexpected error: %#v", err)
+		}
+		if err := printer.PrintObj(test.Input, buf); err != nil {
+			t.Errorf("unexpected error: %#v", err)
+		}
+		if buf.String() != test.Expect {
+			t.Errorf("in %s, expect %q, got %q", test.Name, test.Expect, buf.String(), buf.String())
+		}
+	}
+
 }
 
-func TestPrintJSONPath(t *testing.T) {
-	buf := bytes.NewBuffer([]byte{})
-	printer, found, err := GetPrinter("jsonpath", "{.metadata.name}")
-	if err != nil || !found {
-		t.Fatalf("unexpected error: %#v", err)
+func TestBadPrinter(t *testing.T) {
+	badPrinterTests := []struct {
+		Name           string
+		Format         string
+		FormatArgument string
+		Error          error
+	}{
+		{"empty template", "template", "", fmt.Errorf("template format specified but no template given")},
+		{"bad template", "template", "{{ .Name", fmt.Errorf("error parsing template {{ .Name, template: output:1: unclosed action\n")},
+		{"bad templatefile", "templatefile", "", fmt.Errorf("templatefile format specified but no template file given")},
+		{"bad jsonpath", "jsonpath", "{.Name", fmt.Errorf("error parsing jsonpath {.Name, unclosed action\n")},
 	}
-	unversionedPod := &api.Pod{ObjectMeta: api.ObjectMeta{Name: "foo"}}
-	obj, err := api.Scheme.ConvertToVersion(unversionedPod, testapi.Version())
-	err = printer.PrintObj(obj, buf)
-	if err != nil {
-		t.Fatalf("unexpected error: %s %#v", buf, err)
-	}
-	if buf.String() != "foo" {
-		t.Errorf("unexpected output: %s", buf.String())
-	}
-}
-
-func TestPrintEmptyTemplate(t *testing.T) {
-	if _, _, err := GetPrinter("template", ""); err == nil {
-		t.Errorf("unexpected non-error")
-	}
-}
-
-func TestPrintBadTemplate(t *testing.T) {
-	if _, _, err := GetPrinter("template", "{{ .Name"); err == nil {
-		t.Errorf("unexpected non-error")
-	}
-}
-
-func TestPrintBadTemplateFile(t *testing.T) {
-	if _, _, err := GetPrinter("templatefile", ""); err == nil {
-		t.Errorf("unexpected non-error")
+	for _, test := range badPrinterTests {
+		_, _, err := GetPrinter(test.Format, test.FormatArgument)
+		if err == nil || err.Error() != test.Error.Error() {
+			t.Errorf("in %s, expect %s, got %s", test.Name, test.Error, err)
+		}
 	}
 }
 
@@ -244,15 +201,13 @@ func testPrinter(t *testing.T, printer ResourcePrinter, unmarshalFunc func(data
 	}
 }
 
-type TestPrintType struct {
-	Data string
+func TestYAMLPrinter(t *testing.T) {
+	testPrinter(t, &YAMLPrinter{}, yaml.Unmarshal)
 }
 
-func (*TestPrintType) IsAnAPIObject() {}
-
-type TestUnknownType struct{}
-
-func (*TestUnknownType) IsAnAPIObject() {}
+func TestJSONPrinter(t *testing.T) {
+	testPrinter(t, &JSONPrinter{}, json.Unmarshal)
+}
 
 func PrintCustomType(obj *TestPrintType, w io.Writer, withNamespace bool, wide bool, showAll bool, columnLabels []string) error {
 	_, err := fmt.Fprintf(w, "%s", obj.Data)
@@ -301,27 +256,6 @@ func TestUnknownTypePrinting(t *testing.T) {
 	}
 }
 
-func TestTemplateEmitsVersionedObjects(t *testing.T) {
-	// kind is always blank in memory and set on the wire
-	printer, err := NewTemplatePrinter([]byte(`{{.kind}}`))
-	if err != nil {
-		t.Fatalf("tmpl fail: %v", err)
-	}
-	obj, err := api.Scheme.ConvertToVersion(&api.Pod{}, testapi.Version())
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-
-	buffer := &bytes.Buffer{}
-	err = printer.PrintObj(obj, buffer)
-	if err != nil {
-		t.Fatalf("print fail: %v", err)
-	}
-	if e, a := "Pod", string(buffer.Bytes()); e != a {
-		t.Errorf("Expected %v, got %v", e, a)
-	}
-}
-
 func TestTemplatePanic(t *testing.T) {
 	tmpl := `{{and ((index .currentState.info "foo").state.running.startedAt) .currentState.info.net.state.running.startedAt}}`
 	printer, err := NewTemplatePrinter([]byte(tmpl))

pkg/util/jsonpath/jsonpath_test.go

@@ -118,7 +118,7 @@ func TestStructInput(t *testing.T) {
 		{"union", "{[1,3,4]}", []int{0, 1, 2, 3, 4}, "1 3 4"},
 		{"array", "{[0:2]}", []string{"Monday", "Tudesday"}, "Monday Tudesday"},
 		{"variable", "hello {.Name}", storeData, "hello jsonpath"},
-		{"dict/", "{.Labels.web/html}", storeData, "15"},
+		{"dict/", "{$.Labels.web/html}", storeData, "15"},
 		{"dict-", "{.Labels.k8s-app}", storeData, "20"},
 		{"nest", "{.Bicycle.Color}", storeData, "red"},
 		{"allarray", "{.Book[*].Author}", storeData, "Nigel Rees Evelyn Waugh Herman Melville"},
@@ -210,6 +210,7 @@ func TestKubenates(t *testing.T) {
 			`127.0.0.1 127.0.0.2 127.0.0.3`},
 		{"double range", "{range .items[*]}{range .status.addresses[*]}{.address}, {end}{end}", nodesData,
 			`127.0.0.1, 127.0.0.2, 127.0.0.3, `},
+		{"recursive name", "{..name}", nodesData, `127.0.0.1 127.0.0.2 myself e2e`},
 		{"item name", "{.items[*].metadata.name}", nodesData, `127.0.0.1 127.0.0.2`},
 		{"union nodes capacity", "{.items[*]['metadata.name', 'status.capacity']}", nodesData,
 			`127.0.0.1 127.0.0.2 map[cpu:4] map[cpu:8]`},

pkg/util/jsonpath/parser.go

@@ -151,7 +151,7 @@ func (p *Parser) parseInsideAction(cur *ListNode) error {
 		return fmt.Errorf("unclosed action")
 	case r == ' ':
 		p.consumeText()
-	case r == '@': //the current object, just pass it
+	case r == '@' || r == '$': //the current object, just pass it
 		p.consumeText()
 	case r == '[':
 		return p.parseArray(cur)