Allow mysql_config_include_files to contain raw content

In some cases, specifying a known src path in `mysql_config_include_files`
is not possible / complicated and it may be much cleaner to provide raw
file content to be sent. In that case, we need to use the
`ansible.builtin.copy` module. We can extend the current implementation
by simply filtering on whether `src` or `content` is set in each item
in `mysql_config_include_files`

Author: frazew

README.md

@@ -68,7 +68,7 @@ Whether the global my.cnf should be overwritten each time this role is run. Sett
 mysql_config_include_files: []
 ```
 
-A list of files that should override the default global my.cnf. Each item in the array requires a "src" parameter which is a path to a file. An optional "force" parameter can force the file to be updated each time ansible runs.
+A list of files that should override the default global my.cnf. Each item in the array requires either a "src" parameter which is a path to a file, or both a "content" (file contents) and a "dst" (file name) parameter. An optional "force" parameter can force the file to be updated each time ansible runs.
 
 ```yaml
 mysql_databases: []

defaults/main.yml

@@ -104,6 +104,9 @@ mysql_log: ""
 mysql_config_include_files: []
 #  - src: path/relative/to/playbook/file.cnf
 #  - { src: path/relative/to/playbook/anotherfile.cnf, force: yes }
+#  - content: |
+#      # some included configuration here
+#    dst: yetanotherfile.cnf
 
 # Databases.
 mysql_databases: []

tasks/configure.yml

@@ -24,15 +24,30 @@
     mode: 0755
   when: mysql_config_include_files | length
 
-- name: Copy my.cnf override files into include directory.
+- name: Template my.cnf override files into include directory.
   ansible.builtin.template:
     src: "{{ item.src }}"
     dest: "{{ mysql_config_include_dir }}/{{ item.src | basename }}"
     owner: root
     group: root
     mode: 0644
     force: "{{ item.force | default(False) }}"
-  with_items: "{{ mysql_config_include_files }}"
+  with_items: "{{ mysql_config_include_files | selectattr('src', 'defined') }}"
+  loop_control:
+    label: "{{ item.src | basename }}"
+  notify: restart mysql
+
+- name: Copy my.cnf override files into include directory.
+  ansible.builtin.copy:
+    content: "{{ item.content }}"
+    dest: "{{ mysql_config_include_dir }}/{{ item.dst }}"
+    owner: root
+    group: root
+    mode: 0644
+    force: "{{ item.force | default(False) }}"
+  with_items: "{{ mysql_config_include_files | selectattr('content', 'defined') }}"
+  loop_control:
+    label: "{{ item.dst }}"
   notify: restart mysql
 
 - name: Create slow query log file (if configured).