lib/templates/book.opf.erb
<?xml version='1.0' encoding='utf-8'?>
<package xmlns="http://www.idpf.org/2007/opf" version="2.0" unique-identifier="<%= title %>">
<metadata>
<meta content="cover-image" name="cover"/>
<dc-metadata xmlns:dc="http://purl.org/dc/elements/1.1/">
<dc:title><%= title %></dc:title>
<dc:language>en-gb</dc:language>
<dc:creator><%= author %></dc:creator>
<dc:publisher><%= author %></dc:publisher>
<dc:subject><%= title %></dc:subject>
<dc:identifier id="<%= title %>"><%= title %></dc:identifier>
<dc:date><%= Time.now.to_date %></dc:date>
<dc:description><%= title %></dc:description>
</dc-metadata>
<% if magzine? %>
<x-metadata>
<output content-type="application/x-mobipocket-subscription-magazine" encoding="utf-8"/>
</x-metadata>
<% end %>
</metadata>
<manifest>
<% pages.each_with_index do |page,index|%>
<item href='<%= (index+1).to_s.rjust(3,'0') %>.html' media-type='application/xhtml+xml' id='<%= (index+1).to_s.rjust(3,'0') %>'/>
<% end %>
<item href="cover-image.jpg" id="cover-image" media-type="image/jpeg" />
<item href='contents.html' media-type='application/xhtml+xml' id='contents'/>
<item href='nav-contents.ncx' media-type='application/x-dtbncx+xml' id='nav-contents'/>
</manifest>
<spine toc='nav-contents'>
<itemref idref='contents'/>
<% pages.each_with_index do |page,index| %>
<itemref idref='<%= (index+1).to_s.rjust(3,'0') %>'/>
<% end %>
</spine>
<guide>
<reference href='contents.html' type='toc' title='Table of Contents'/>
<reference href="cover-image.jpg" type="cover" title="Cover"/>
</guide>
</package>