a general role to DRY out specific roles.

playbooks/roles/edx_service/defaults/main.yml

+---
+#
+# edX Configuration
+#
+# github:     https://github.com/edx/configuration
+# wiki:       https://github.com/edx/configuration/wiki
+# code style: https://github.com/edx/configuration/wiki/Ansible-Coding-Conventions
+# license:    https://github.com/edx/configuration/blob/master/LICENSE.TXT
+#
+##
+# Defaults for role edx_service
+# 
+
+#
+# vars are namespace with the module name.
+#
+edx_service_role_name: edx_service
+
+#
+# OS packages
+#
+
+edx_service_debian_pkgs: []
+
+edx_service_redhat_pkgs: []

playbooks/roles/edx_service/handlers/main.yml

+---
+#
+# edX Configuration
+#
+# github:     https://github.com/edx/configuration
+# wiki:       https://github.com/edx/configuration/wiki
+# code style: https://github.com/edx/configuration/wiki/Ansible-Coding-Conventions
+# license:    https://github.com/edx/configuration/blob/master/LICENSE.TXT
+#
+#
+#
+# Handlers for role edx_service
+# 
+# Overview:
+# 
+#
+- name: edx_service | notify me
+  debug: msg="stub handler"

playbooks/roles/edx_service/meta/main.yml

+---
+#
+# edX Configuration
+#
+# github:     https://github.com/edx/configuration
+# wiki:       https://github.com/edx/configuration/wiki
+# code style: https://github.com/edx/configuration/wiki/Ansible-Coding-Conventions
+# license:    https://github.com/edx/configuration/blob/master/LICENSE.TXT
+#
+##
+# Role includes for role edx_service
+# 
+# Example:
+#
+# dependencies:
+#   - {
+#   role: my_role 
+#   my_role_var0: "foo"
+#   my_role_var1: "bar"
+# }

playbooks/roles/edx_service/tasks/main.yml

+---
+#
+# edX Configuration
+#
+# github:     https://github.com/edx/configuration
+# wiki:       https://github.com/edx/configuration/wiki
+# code style: https://github.com/edx/configuration/wiki/Ansible-Coding-Conventions
+# license:    https://github.com/edx/configuration/blob/master/LICENSE.TXT
+#
+#
+#
+# Tasks for role edx_service
+# 
+# Overview:
+# 
+#
+# Dependencies:
+#
+# 
+# Example play:
+#
+#
+
+- name: create application user
+  user: >
+    name="{{ edx_service_name }}"
+    home="{{ COMMON_APP_DIR }}/{{ edx_service_name }}"
+    createhome=no
+    shell=/bin/false
+
+- name: create edx_service app and venv dir
+  file: >
+    path="{{ item }}"
+    state=directory
+    owner="{{ edx_service_name }}"
+    group="{{ common_web_group }}"
+  with_items:
+    - "{{ COMMON_APP_DIR }}/{{ edx_service_name }}"
+    - "{{ COMMON_APP_DIR }}/{{ edx_service_name }}/venvs"
+
+- name: install a bunch of system packages on which edx_service relies
+  apt: pkg={{ item }} state=present
+  with_items: "{{ edx_service_name }}_debian_pkgs"
+  when: ansible_distribution in common_debian_variants
+
+- name: install a bunch of system packages on which edx_service relies
+  yum: pkg={{ item }} state=present
+  with_items: "{{ edx_service_name }}_redhat_pkgs"
+  when: ansible_distribution in common_redhat_variants
\ No newline at end of file