Ansible apt module to execute with sudo - ansible

Question

I'm trying to get ansible to execute sudo apt-get update. I already have the sudoers setup to run without a password and it works if I login as the user ansible is using and execute sudo apt-get update. If I use the following ansible playbook
---
- name: updates
hosts: pis
tasks:
- name: Update APT
become: true
apt:
update_cache: yes
It will give me the following error
fatal: [127.0.0.1]: FAILED! => {"changed": false, "module_stderr": "Shared connection to 127.0.0.1 closed.\r\n", "module_stdout": "sudo: a password is required\r\n", "msg": "MODULE FAILURE\nSee stdout/stderr for the exact error", "rc": 1}
but the following playbook works fine
---
- name: updates
hosts: pis
tasks:
- name: Update APT
command: sudo apt-get update

Answer 1

When using become: yes the connection will try to spawn shell as root (as you haven't specified become_user).
It seems you have access to run sudo apt-get update without password, i.e:
/etc/sudodoers may contain something similar to this:
ansible ALL=(ALL) NOPASSWD: /bin/apt-get update
To replicate the issue, login as user ansible and issue a command sudo -i
If you're using a dedicated user (ansible ?) for all ansible connectivity, you might want to give that user access to all commands via sudo without password. Read Here this is however not the best practice, you are always better off giving access to specific commands for security reasons
Add the following line to /etc/sudoers file using visudo /etc/sudoers
ansible ALL=(ALL) NOPASSWD:ALL
If you opt for this, I would also advise to use a key-pair authentication for this privileged account rather than password authentication. More info