[Cleanup] Cleanup the mysql role

Remove the useless call for `cat` as `grep` take a file as it's second
argument that tell it to search for the pattern in a specific file
instead of whatever is passed to it through stdin.

Name both task defining the position of the config directory for
self-documentation purposes (and please ansible-lint defaults).

Change role description to it's description in the readme instead of the
default description asking for the role to be described.

Don't compare to empty string, an empty string is already false while a
non-empty string is true.

mysql/meta/main.yml

@@ -1,6 +1,6 @@
 galaxy_info:
   author: Evolix
-  description: your description
+  description: Install and configure mysql
 
   issue_tracker_url: https://gitea.evolix.org/evolix/ansible-roles/issues
 

mysql/tasks/config_jessie.yml

@@ -1,6 +1,7 @@
 ---
 
-- set_fact:
+- name: "Define the config directory of mysql"
+  set_fact:
     mysql_config_directory: /etc/mysql/conf.d
 
 - name: "Copy MySQL defaults config file (jessie)"

mysql/tasks/config_stretch.yml

@@ -1,6 +1,7 @@
 ---
 
-- set_fact:
+- name: "Define the config directory of mysql"
+  set_fact:
     mysql_config_directory: /etc/mysql/mariadb.conf.d
 
 - name: "Copy MySQL defaults config file (Debian 9 or later)"

mysql/tasks/datadir.yml

@@ -14,7 +14,7 @@
     register: mysql_current_real_datadir_test
   tags:
     - mysql
-  when: mysql_custom_datadir != ''
+  when: mysql_custom_datadir
 
 - block:
   - name: MySQL is stopped
@@ -40,6 +40,6 @@
   tags:
     - mysql
   when:
-    - mysql_custom_datadir != ''
+    - mysql_custom_datadir
     - mysql_custom_datadir != mysql_current_real_datadir_test.stdout
     - not mysql_custom_datadir_test.stat.exists

mysql/tasks/logdir.yml

@@ -14,7 +14,7 @@
     register: mysql_current_real_logdir_test
   tags:
     - mysql
-  when: mysql_custom_logdir != ''
+  when: mysql_custom_logdir
 
 - block:
   - name: MySQL is stopped
@@ -40,6 +40,6 @@
   tags:
     - mysql
   when:
-    - mysql_custom_logdir != ''
+    - mysql_custom_logdir
     - mysql_custom_logdir != mysql_current_real_logdir_test.stdout
     - not mysql_custom_logdir_test.stat.exists

mysql/tasks/tmpdir.yml

@@ -20,4 +20,4 @@
     notify: "{{ mysql_restart_handler_name }}"
     tags:
       - mysql
-  when: mysql_custom_tmpdir != ''
+  when: mysql_custom_tmpdir

mysql/tasks/utils.yml

@@ -41,7 +41,7 @@
   when: ansible_distribution_major_version is version('10', '>=')
 
 - name: Read debian-sys-maint password
-  shell: 'cat /etc/mysql/debian.cnf | grep -m1 "password = .*" | cut -d" " -f3'
+  shell: 'grep -m1 "password = .*" /etc/mysql/debian.cnf | cut -d" " -f3'
   register: mysql_debian_password
   changed_when: False
   check_mode: no