Yocto Jethro: how do I add user to sudoers list

I added a new user as follows

inherit extrausers
EXTRA_USERS_PARAMS = "useradd -P p@ssW0rd user1;"

I am trying to find how to add users to sudoers list. Is there a class like extrausers

Update-1:

In class classes/extrausers.bbclass I see usermod supported. Will the following work?

inherit extrausers
EXTRA_USERS_PARAMS = "useradd -P p@ssW0rd user1;\
                      usermod -aG sudo user1"

Update-2:

I tried adding IMAGE_INSTALL_append += " sudo " and

inherit extrausers
EXTRA_USERS_PARAMS = "useradd -P foobar -G sudo user1;"

But that does not help me in achieving the effect of adding user1 to sudoers list. I see following error when I do sudo -v

Sorry, user user1 may not run sudo on <machine-name>.

Update-3:

I found that the sudoers file has the sudo group commented as follows: # %sudo ALL=(ALL) ALL Hence the reason even adding user1 to group sudo didn't help

Rather than adding user1 to group sudo I adopted approach of adding a drop-in file under /etc/sudoers.d/0001_user1 using recipes-extended/sudo/sudo_1.8.14p3.bbappend

do_install_append () {
    echo "user1 ALL=(ALL) ALL" > ${D}${sysconfdir}/sudoers.d/001_first
}

Now I need help in understanding which of following is a better approach in terms of security?

• uncomment sudo line in /etc/sudoers and adding user1 to /etc/sudoers
• adding user1 in /etc/sudoers.d/001_first

So there are two approaches to add an user with sudo capability

• Add user to sudo group and enable sudo group in /etc/sudoers
• Create a file under ${D}${sysconfdir}/sudoers.d/ and add the sudo rule for user there.

Now which approach is suitable for your distro is well answered in /etc/sudoers vs /etc/sudoers.d/ file for enabling sudo for a user