Support the new secure_password for xpack notifications

[MikeBairdRocks]

Describe the feature:
when es_mail_config.pass is defined should know the elastic version and generate the secure_password in the keystore if >=7.0.

Docs:

• Email Notification Settings
• Security Settings

Also leave out the pass in elasticsearch.yml.j2 since this will prevent 7 from starting with an invalid attribute setting.

Some sudo code:

- name: Create Smtp password for notifications
  become: yes
  shell: echo "{{es_mail_config['pass']}}" | {{es_home}}/bin/elasticsearch-keystore add -x 'xpack.notification.email.account.{{ es_mail_config['account'] }}.smtp.secure_password'
  when:
    - es_mail_config['pass'] is defined and list_keystore is defined
  environment:
    ES_PATH_CONF: "{{ es_conf_dir }}"
  no_log: true

[Crazybus]

Makes a lot of sense. Since there are other secure settings besides this I think it would be a lot cleaner to instead implement a way to populate the keystore in a generic way. So instead of hard-coding it for this specific value just having a way to add files and strings to the keystore in a generic way like:

es_keystore:
  files:
    keystore_key: /path/to/file
  strings:
    xpack.notification.email.account.{{ es_mail_config['account'] }}.smtp.secure_password: {{ password_from_somwhere_secure }}

[jmlrt]

Related to #503

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[rs-garrick]

I ran into this problem today. MikeBairdRocks's suggestion looked pretty good.

#660

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[botelastic]

This issue has been automatically closed because it has not had recent activity since being marked as stale.