cluster/tools/kartongips/cmd/diff.go

// Copyright 2017 The kubecfg authors
//
//
//    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 cmd

import (
	"fmt"
	"os"

	"github.com/mattn/go-isatty"
	"github.com/spf13/cobra"

	"code.hackerspace.pl/hscloud/cluster/tools/kartongips/pkg/kubecfg"
)

const (
	// TODO(b/49): remove this flag
	flagDiffStrategy = "diff-strategy"
	flagOmitSecrets  = "omit-secrets"
)

func init() {
	diffCmd.PersistentFlags().String(flagDiffStrategy, "", "Diff strategy - no op (will be removed soon)")
	diffCmd.PersistentFlags().Bool(flagOmitSecrets, false, "hide secret details when showing diff")
	RootCmd.AddCommand(diffCmd)
}

// nagStrategy nags the user about selecting strategy=subset explicitly -
// either hint at not having to use it if subset is specified, or fail hard if
// something else is set.
//
// TODO(b/49): remove this
func nagStrategy(chosen string) {
	if chosen == "" {
		return
	}
	color := isatty.IsTerminal(os.Stdout.Fd())

	if chosen == "subset" {
		if color {
			fmt.Fprintf(os.Stdout, "\x1b[92m")
		}
		fmt.Fprintf(os.Stdout, "--diff-strategy=subset is now the default behaviour of kartongips/kubecfg, no need to explicitly set it.\n")
		fmt.Fprintf(os.Stdout, "Work on your muscle memory and fix your scripts! This flag will be removed soon (see: b.hswaw.net/49).\n")
		if color {
			fmt.Fprintf(os.Stdout, "\x1b[0m")
		}
		return
	}

	fmt.Fprintf(os.Stderr, "--diff-strategy is deprecated, the default behaviour is now 'subset' and all other modes of operation have been removed. See: b.hswaw.net/49.\n")
	os.Exit(1)
}

var diffCmd = &cobra.Command{
	Use:   "diff",
	Short: "Display differences between server and local config",
	Args:  cobra.ArbitraryArgs,
	RunE: func(cmd *cobra.Command, args []string) error {
		flags := cmd.Flags()
		var err error

		c := kubecfg.DiffCmd{}

		diffStrategy, err := flags.GetString(flagDiffStrategy)
		if err != nil {
			return err
		}
		nagStrategy(diffStrategy)

		c.OmitSecrets, err = flags.GetBool(flagOmitSecrets)
		if err != nil {
			return err
		}

		c.Client, c.Mapper, _, err = getDynamicClients(cmd)
		if err != nil {
			return err
		}

		c.DefaultNamespace, err = defaultNamespace(clientConfig)
		if err != nil {
			return err
		}

		objs, err := readObjs(cmd, args)
		if err != nil {
			return err
		}

		err = c.Run(cmd.Context(), objs, cmd.OutOrStdout())
		nagStrategy(diffStrategy)
		return err
	},
}