feat(unsupported): prevent formula running on unsupported minions

* https://freenode.logbot.info/saltstack-formulas/20190421#c2129159
* Use `failhard` to prevent execution if `unsupported` has been set
* Show reason why minion is `unsupported`
* Allow `unsupported` to be overridden at each level within the map

Author: myii

template/config/init.sls

@@ -1,5 +1,9 @@
 # -*- coding: utf-8 -*-
 # vim: ft=sls
 
+{%- set tplroot = tpldir.split('/')[0] %}
+{%- set sls_fail_if_unsupported = tplroot ~ '.unsupported' %}
+
 include:
+  - {{ sls_fail_if_unsupported }}
   - .file

template/init.sls

@@ -1,7 +1,11 @@
 # -*- coding: utf-8 -*-
 # vim: ft=sls
 
+{%- set tplroot = tpldir.split('/')[0] %}
+{%- set sls_fail_if_unsupported = tplroot ~ '.unsupported' %}
+
 include:
+  - {{ sls_fail_if_unsupported }}
   - .package
   - .config
   - .service

template/osfamilymap.yaml

@@ -33,8 +33,11 @@ FreeBSD: {}
 
 OpenBSD: {}
 
-Solaris: {}
+Solaris:
+  unsupported: 'osfamily: Solaris.'
 
-Windows: {}
+Windows:
+  unsupported: 'osfamily: Windows.'
 
-MacOS: {}
+MacOS:
+  unsupported: 'osfamily: MacOS.'

template/osfingermap.yaml

@@ -10,11 +10,15 @@
 # the `os_finger` grain.
 ---
 # os: Ubuntu
+Ubuntu-14.04:
+  unsupported: 'osfinger: Ubuntu 14.04 (does not use `systemd`).'
+Ubuntu-16.04: {}
 Ubuntu-18.04:
   config: /etc/template.d/custom-ubuntu-18.04.conf
 
 # os: CentOS
 CentOS-6:
-  pkg: template-centos-6
-  config: /etc/template.d/custom-centos-6.conf
-CentOS-7: {}
+  unsupported: 'osfinger: CentOS 6 (does not use `systemd`).'
+CentOS-7:
+  pkg: template-centos-7
+  config: /etc/template.d/custom-centos-7.conf

template/osmap.yaml

@@ -14,7 +14,8 @@ Ubuntu:
   pkg: template-ubuntu
   config: /etc/template.d/custom-ubuntu.conf
 
-Raspbian: {}
+Raspbian:
+  unsupported: 'os: Raspbian (`armhf` architecture).'
 
 # os_family: RedHat
 Fedora:

template/package/init.sls

@@ -1,5 +1,9 @@
 # -*- coding: utf-8 -*-
 # vim: ft=sls
 
+{%- set tplroot = tpldir.split('/')[0] %}
+{%- set sls_fail_if_unsupported = tplroot ~ '.unsupported' %}
+
 include:
+  - {{ sls_fail_if_unsupported }}
   - .install

template/service/init.sls

@@ -1,5 +1,9 @@
 # -*- coding: utf-8 -*-
 # vim: ft=sls
 
+{%- set tplroot = tpldir.split('/')[0] %}
+{%- set sls_fail_if_unsupported = tplroot ~ '.unsupported' %}
+
 include:
+  - {{ sls_fail_if_unsupported }}
   - .running

template/unsupported.sls

@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+# vim: ft=sls
+
+{#- Get the `tplroot` from `tpldir` #}
+{%- set tplroot = tpldir.split('/')[0] %}
+{%- from tplroot ~ "/map.jinja" import template with context %}
+
+{%- if template.unsupported is defined and template.unsupported %}
+template-unsupported-test-fail:
+  test.fail_without_changes:
+    - name: |
+
+
+        #######################################
+        # Unsupported minion for this formula #
+        #######################################
+        {{ template.unsupported }}
+    - failhard: True
+{%- endif %}