include distribution specific vars from files

tasks/include-vars.yml

@@ -0,0 +1,8 @@
+---
+- name: Load a variable file based on the OS type, or a default if not found.
+  include_vars: "{{ item }}"
+  with_first_found:
+    - "{{ ansible_distribution }}-{{ ansible_distribution_version }}.yml"
+    - "{{ ansible_distribution }}.yml"
+    - "{{ ansible_os_family }}.yml"
+    - "default.yml"

tasks/install-with-package.yml

@@ -1,14 +1,4 @@
 ---
-- name: Define certbot_package (Ubuntu 16.04).
-  set_fact:
-    certbot_package: letsencrypt
-  when: ansible_distribution == 'Ubuntu' and ansible_distribution_version == '16.04'
-
-- name: Define certbot_package.
-  set_fact:
-    certbot_package: certbot
-  when: certbot_package is undefined
-
 - name: Install Certbot.
   package: "name={{ certbot_package }} state=present"
 

tasks/main.yml

@@ -1,4 +1,6 @@
 ---
+- include: include-vars.yml
+
 - include: install-with-package.yml
   when: not certbot_install_from_source
 

vars/Ubuntu-16.04.yml

@@ -0,0 +1 @@
+certbot_package: letsencrypt

vars/default.yml

@@ -0,0 +1,2 @@
+---
+certbot_package: certbot