rootCmd MarkPersistentFlagRequired does not raise error

[niski84]

Using spf13/Cobra for cli flag parsing.

root command has a field marked required:

rootCmd.PersistentFlags().StringVarP(&configFilePath, "config", "c","", "REQUIRED: config file")
    rootCmd.MarkPersistentFlagRequired("config")    
    rootCmd.MarkFlagRequired("config")

However, cobra does not raise an error if it's the root command.

If I add a subcommand and add a required field, .MarkFlagRequired raises an error as expected if the argument is not provided on the command line.

[kjaskiewiczz]

I'm facing the same issue. Before the upgrade, I've been using revision a1f051bc3eba734da4772d60e2d677f47cf93ef4 and it was working (at least this issue was not present there).

[mattthym]

I came across this issue in one of my CLI tools built with cobra in which I have a command for which I have defined some flags which I marked as required, which works fine as long as I define the flag with Flags().StringP(...) but does not work if I use Flags().StringVarP(...) so I think it does not relate to the flags being persistent.

Code to replicate the issue:

package cmd

import (
	"fmt"

	"github.com/spf13/cobra"
)

var testCmd = &cobra.Command{
	Use: "test",
	Run: func(cmd *cobra.Command, args []string) {
		fmt.Println(Foo)
	},
}

var Foo string

func init() {
	rootCmd.AddCommand(testCmd)

	testCmd.Flags().StringVarP(&Foo, "foo", "f", "", "A help for foo")
	testCmd.MarkFlagRequired(Foo)
}

The problem is, that the command executes without printing any error, unlike how it does when defining flags with Flags().StringP().

This works just fine:

package cmd

import (
	"fmt"

	"github.com/spf13/cobra"
)

var testCmd = &cobra.Command{
	Use: "test",
	RunE: func(cmd *cobra.Command, args []string) error {
		Foo, err := cmd.Flags().GetString("foo")
		if err != nil {
			return err
		}
		fmt.Println(Foo)
		return nil
	},
}

func init() {
	rootCmd.AddCommand(testCmd)

	testCmd.Flags().StringP("foo", "f", "", "A help for foo")
	testCmd.MarkFlagRequired("foo")
}

[ashishgalagali]

https://github.com/spf13/cobra/issues/206#issuecomment-471959800

[github-actions[bot]]

This issue is being marked as stale due to a long period of inactivity

[dghant1024]

I'm really surprised this code below doesn't work either:

         rootCmd.PersistentFlags().StringP("needed-file", "i", "", "needed file path. Defaults (required)")
	 if err := rootCmd.MarkPersistentFlagRequired("needed-file"); err != nil {
		fmt.Println("HELLO people")
	}

Error not raise if in rootCmd. Any thoughts are this are welcomed.

[alexrs]

I'm having the same problem with:

package cmd

import (
	"fmt"

	"github.com/spf13/cobra"
)

var (
	// Used for flags.
	Region string
	Test   string

	rootCmd = &cobra.Command{
		Use: "cli-test",
	}
)

// Execute executes the root command.
func Execute() {
	fmt.Println(Test)
}

func init() {
	rootCmd.PersistentFlags().StringVarP(&Region, "region", "r", "", "region (required)")
	rootCmd.PersistentFlags().StringVarP(&Test, "test", "t", "", "Test flag")
	rootCmd.MarkPersistentFlagRequired("region")
}

If I call my CLI without -r, it does not return any errors.

[elulcao]

I'm facing the same issue mentioned here, however I feel this is not a problem with Cobra and root commands but an interpretation maybe. In my case the default value, as well examples here, is "" an empty string which is not nil nor empty so it seems that this empty value is correct for the persistent and required flag.

rootcmd.PersistentFlags().String("config-file", "", "The config file that contains the information to add the entry")
rootcmd.MarkPersistentFlagRequired("config-file")

If we add some extra traces we will see that a config file wasn't found:

2023-01-16T11:04:00.810-0600 [ERROR] mycmd: error adding an entry: open : no such file or directory

Previous output is actually including the empty string like adding an open <empty string here>: no such file, this make me think that Cobra is OK but missing documentation issue. It would be better if Cobra doc mention that MarkPersistentFlagRequired() interprets empty string as valid value and hence Cobra User should add some extra code to check situations where empty values are misinterpreted.