testing out moving off bash

Signed-off-by: James Strong <james.strong@chainguard.dev>

ingressctl/cmd/root.go

@@ -0,0 +1,66 @@
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var rootCmd = &cobra.Command{
+	Use:   "ingressctl",
+	Short: "CLI",
+	Long:  `CLI for managing ingress-nginx repo`,
+}
+
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func init() {
+	rootCmd.AddCommand(newCmdCompletion(os.Stdout))
+	rootCmd.SetOut(os.Stdout)
+	rootCmd.SetErr(os.Stderr)
+}
+
+const completionExample = `
+# Installing bash completion on macOS using homebrew
+## If running Bash 3.2 included with macOS
+	brew install bash-completion
+## or, if running Bash 4.1+
+	brew install bash-completion@2
+`
+
+func newCmdCompletion(out io.Writer) *cobra.Command {
+	cmd := &cobra.Command{
+		Use:     "completion [shell]",
+		Short:   "Output shell completion code",
+		Long:    ``,
+		Example: completionExample,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runCompletion(out, cmd, args)
+		},
+		ValidArgs: []string{"bash", "zsh", "fish"},
+	}
+
+	return cmd
+}
+
+func runCompletion(out io.Writer, cmd *cobra.Command, args []string) error {
+	if len(args) > 1 {
+		return fmt.Errorf("too many arguments; expected only the shell type: %s", args)
+	}
+
+	if len(args) == 0 || args[0] == "bash" {
+		return cmd.Root().GenBashCompletion(out)
+	} else if args[0] == "zsh" {
+		return cmd.Root().GenZshCompletion(out)
+	} else if args[0] == "fish" {
+		return cmd.Root().GenFishCompletion(out, true)
+	}
+	return fmt.Errorf("unsupported shell: %s", args[0])
+}