Added option to create swap, updated README, resolves #14.

Author: jcalazan

README.md

@@ -93,6 +93,38 @@ If you're testing with vagrant, you can use this command:
 ansible-playbook -i vagrant_ansible_inventory_default --private-key=~/.vagrant.d/insecure_private_key -v vagrant.yml
 ```
 
+## Advanced Options
+
+### Creating a swap file
+
+By default, the playbook won't create a swap file.  To create/enable swap, simply change the values in `roles/base/vars/main.yml`. 
+
+You can also override these values in the main playbook, for example:
+
+```
+---
+
+- name: Create a {{ application_name }} virtual machine via vagrant
+  hosts: all
+  sudo: yes
+  sudo_user: root
+  remote_user: vagrant
+  vars:
+    - setup_git_repo: yes
+    - update_apt_cache: yes
+  vars_files:
+    - env_vars/base.yml
+    - env_vars/local.yml
+
+  roles:
+    - { role: base, create_swap_file: yes, swap_file_size_kb: 1024 }
+    - db
+    - web
+    - memcached
+```
+
+This will create and mount a 1GB swap.  Note that block size is 1024, so the size of the swap file will be 1024 x `swap_file_size_kb`.
+
 ## Useful Links
 - [Ansible - Getting Started](http://docs.ansible.com/intro_getting_started.html)
 - [Ansible - Best Practices](http://docs.ansible.com/playbooks_best_practices.html)

roles/base/tasks/create_swap_file.yml

@@ -0,0 +1,36 @@
+- name: Create swap file
+  command: dd if=/dev/zero of={{ swap_file_path }} bs=1024 count={{ swap_file_size_kb }}k
+           creates="{{ swap_file_path }}"
+  tags: swap.file.create
+
+- name: Change swap file permissions
+  file: path="{{ swap_file_path }}"
+        owner=root
+        group=root
+        mode=0600
+  tags: swap.file.permissions
+
+- name: Check swap file type
+  command: file {{ swap_file_path }}
+  register: swapfile
+  tags: swap.file.mkswap
+
+- name: Make swap file
+  command: "sudo mkswap {{ swap_file_path }}"
+  when: swapfile.stdout.find('swap file') == -1
+  tags: swap.file.mkswap
+
+- name: Write swap entry in fstab
+  mount: name=none
+         src={{ swap_file_path }}
+         fstype=swap
+         opts=sw
+         passno=0
+         dump=0
+         state=present
+  tags: swap.fstab
+
+- name: Mount swap
+  command: "swapon {{ swap_file_path }}"
+  when: ansible_swaptotal_mb < 1
+  tags: swap.file.swapon

roles/base/tasks/main.yml

@@ -1,5 +1,9 @@
 ---
 
+- include: create_swap_file.yml
+  when: create_swap_file
+  tags: swap
+
 - name: Ensure bash, OpenSSl, and libssl are the latest versions
   apt: name={{ item }} update_cache={{ update_apt_cache }} state=latest
   with_items:

roles/base/vars/main.yml

@@ -0,0 +1,5 @@
+---
+
+create_swap_file: no
+swap_file_path: /swapfile
+swap_file_size_kb: 512