Cobra: rootCmd MarkPersistentFlagRequired does not raise error

Created on 17 Sep 2018 · 4Comments · Source: spf13/cobra

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.

kinstale

Source

niski84

👀1

Most helpful comment

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")
}

mattthym on 13 Nov 2018

👍3

All 4 comments

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).

kjaskiewiczz on 4 Oct 2018

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")
}

mattthym on 13 Nov 2018

👍3

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