Ansible Install MySql 5.7 - Set Root User Password

Question

I've recently upgraded my vagrant from ubuntu/trusty-64 to bento/ubuntu-16.04. With that MySQL was updated to 5.7. I've made several updates to my playbook, but I keep getting stuck when setting the root user's password.

In the past (before 5.7) the following was sufficient:

- name: MySQL | Set the root password.
  mysql_user: 
    name=root 
    host=localhost
    password={{ mysql_root_password }}
  become: true

In my playbook this is tested by attempting to delete an anonymous user.

- name: MySQL | Delete anonymous MySQL server user for {{ server_hostname }}
  mysql_user: 
    name="" 
    host="{{ server_hostname }}" 
    state="absent" 
    login_user=root 
    login_password={{ mysql_root_password }}

However, now my playbook fails at this step, returning:

"Access denied for user 'root'@'localhost'"

TASK [mysql : MySQL | Delete anonymous MySQL server user for vagrant] **********
task path: /Users/jonrobinson/vagrant/survey/playbooks/roles/mysql/tasks/mysql.yml:51
fatal: [vagrant]: FAILED! => {"changed": false, "failed": true, "msg": "unable to connect to database, check login_user and login_password are correct or /home/vagrant/.my.cnf has the credentials. Exception message: (1698, \"Access denied for user 'root'@'localhost'\")"}

I've tried several things:

1. Setting the password blank for root user mysql_root_password=""
2. Attempting to delete the root user then recreate it with Ansible. I get same error probably because it's trying to act at the root user.
3. Manually updating the root password in mysql. - This also doesn't appear to work (password isn't recognized) unless I delete the root user and recreate it with all the permissions. Just updating the root user password appears to have no change.

My Full MySQL YAML:

---
- name: MySQL | install mysql packages
  apt: pkg={{ item }} state=installed
  become: true
  with_items:    
   - mysql-client
   - mysql-common
   - mysql-server
   - python-mysqldb

- name: MySQL | create MySQL configuration file
  template:
    src=my.cnf.j2
    dest=/etc/mysql/my.cnf
    backup=yes
    owner=root
    group=root
    mode=0644
  become: true

- name: MySQL | create MySQLD configuration file
  template:
    src=mysqld.cnf.j2
    dest=/etc/mysql/conf.d/mysqld.cnf
    backup=yes
    owner=root
    group=root
    mode=0644
  become: true

- name: MySQL | restart mysql
  service: name=mysql state=restarted
  become: true

- name: MySQL | Set the root password.
  mysql_user: 
    name=root 
    host=localhost
    password={{ mysql_root_password }}
  become: true

- name: MySQL | Config for easy access as root user
  template: src=mysql_root.my.cnf.j2 dest=/root/.my.cnf
  become: true

- name: MySQL | Config for easy access as root user
  template: src=mysql_root.my.cnf.j2 dest={{ home_dir }}/.my.cnf
  when: "'{{ user }}' != 'root'"

- name: MySQL | Delete anonymous MySQL server user for {{ server_hostname }}
  mysql_user: name="" host="{{ server_hostname }}" state="absent" login_user=root login_password={{ mysql_root_password }}

- name: MySQL | Delete anonymous MySQL server user for localhost
  mysql_user: name="" state="absent" host=localhost login_user=root login_password={{ mysql_root_password }}

- name: MySQL | Secure the MySQL root user for IPV6 localhost (::1)
  mysql_user: name="root" password="{{ mysql_root_password }}" host="::1" login_user=root login_password={{ mysql_root_password }}

- name: MySQL | Secure the MySQL root user for IPV4 localhost (127.0.0.1)
  mysql_user: name="root" password="{{ mysql_root_password }}" host="127.0.0.1" login_user=root login_password={{ mysql_root_password }}

- name: MySQL | Secure the MySQL root user for localhost domain (localhost)
  mysql_user: name="root" password="{{ mysql_root_password }}" host="localhost" login_user=root login_password={{ mysql_root_password }}

- name: MySQL | Secure the MySQL root user for {{ server_hostname }} domain
  mysql_user: name="root" password="{{ mysql_root_password }}" host="{{ server_hostname }}" login_user=root login_password={{ mysql_root_password }}

- name: MySQL | Remove the MySQL test database
  mysql_db: db=test state=absent login_user=root login_password={{ mysql_root_password }}

- name: MySQL | create application database user
  mysql_user: name={{ dbuser }} password={{ dbpass }} priv=*.*:ALL host='%' state=present login_password={{ mysql_root_password }} login_user=root

- name: MySQL | restart mysql
  service: name=mysql state=restarted
  become: true

Answer 1

I was able to figure it out. The gist of the problem had to do with mysql 5.7 using auth_socket for the root user when no password is provided. See the following: "That plugin doesn’t care and doesn’t need a password. It just checks if the user is connecting using a UNIX socket and then compares the username. "

When this is the case you cannot update the password using:

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('test');

And instead must use:

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password='test';

Solution 1: However, Ansible, as of version 2.0.2 didn't account for this. I was able to get around this by setting the password before MySql is installed

- name: Specify MySQL root password before installing
  debconf: name='mysql-server' question='mysql-server/root_password' value='{{mysql_root_password | quote}}' vtype='password'
  become: true

- name: Confirm MySQL root password before installing
  debconf: name='mysql-server' question='mysql-server/root_password_again' value='{{mysql_root_password | quote}}' vtype='password'
  become: true

- name: MySQL | install mysql packages
  apt: pkg={{ item }} state=installed
  become: true
  with_items:    
   - mysql-client
   - mysql-common
   - mysql-server
   - python-mysqldb
  ...

However, this has also since been addressed by Ansible

Solution 2: The easiest solution is just to upgrade Ansible to 2.2.1