feat: add hgctl manifest support (#554)

Signed-off-by: bitliu <bitliu@tencent.com>

pkg/cmd/hgctl/config_bootstrap.go

@@ -0,0 +1,65 @@
+// Copyright (c) 2022 Alibaba Group Holding Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package hgctl
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+	cmdutil "k8s.io/kubectl/pkg/cmd/util"
+)
+
+func bootstrapConfigCmd() *cobra.Command {
+	configCmd := &cobra.Command{
+		Use:     "bootstrap <pod-name>",
+		Aliases: []string{"b"},
+		Short:   "Retrieves bootstrap Envoy xDS resources from the specified Higress Gateway Pod",
+		Long:    `Retrieves information about bootstrap Envoy xDS resources from the specified Higress Gateway Pod`,
+		Example: `  # Retrieve summary about bootstrap configuration for a given pod from Envoy.
+  hgctl gateway-config bootstrap <pod-name> -n <pod-namespace>
+
+  # Retrieve full configuration dump as YAML
+  hgctl gateway-config bootstrap <pod-name> -n <pod-namespace> -o yaml
+
+  # Retrieve full configuration dump with short syntax
+  hgctl gc b <pod-name> -n <pod-namespace>
+`,
+		Run: func(c *cobra.Command, args []string) {
+			cmdutil.CheckErr(runBootstrapConfig(c, args))
+		},
+	}
+
+	return configCmd
+}
+
+func runBootstrapConfig(c *cobra.Command, args []string) error {
+	configDump, err := retrieveConfigDump(args, false)
+	if err != nil {
+		return err
+	}
+
+	bootstrap, err := GetXDSResource(BootstrapEnvoyConfigType, configDump)
+	if err != nil {
+		return err
+	}
+
+	out, err := formatGatewayConfig(bootstrap, output)
+	if err != nil {
+		return err
+	}
+
+	_, err = fmt.Fprintln(c.OutOrStdout(), string(out))
+	return err
+}