Summary
Store multiple attributes and values using a text column. Not for everyday use, but has situations where it can save on the number of columns and/or models needed to accomplish a task.rails model 12:04
Resources
Summary
Create the users scaffold with name and properties
# bash
rails g scaffold users name properties:textAdd serialized attributes on `properties` and the singleton methods for our serialized attributes.
# user.rb
serialize :properties, Hash
after_initialize do
%w(twitter_handle github_username).each do |property|
define_singleton_method property do
properties[property]
end
end
endAdd the properties array to the allowed parameters
# users_controller.rb
def user_params
#params.require(:user).permit(:name, properties: [:twitter_handle, :github_username])
params.require(:user).permit(*user_attributes)
end
def user_attributes
property_fields = [:twitter_handle, :github_username]
[].tap do |attributes|
attributes << :name
attributes << { properties: property_fields }
end
end
def user_attributes
property_fields = []
params.require(:user).each do |key, p|
property_fields << p.keys if key == 'properties'
end
property_fields = [:twitter_handle, :github_username]
[].tap do |attributes|
attributes << :name
attributes << { properties: property_fields }
end
end
Create the form fields for the serialized attributes
# _form.html.erb
<%= f.simple_fields_for :properties do |p| %>
<%= p.input :twitter_handle, input_html: { value: @user.properties[:twitter_handle] } %>
<%= p.input :github_username, input_html: { value: @user.properties[:github_username] } %>
<% end %>Display the parameters
# index.html.erb
<table class='table table-bordered table-condensed'>
<thead>
<tr>
<th>Name</th>
<th>Twitter</th>
<th>Github</th>
<th colspan="3"></th>
</tr>
</thead>
<tbody>
<% @users.each do |user| %>
<tr>
<td><%= user.name %></td>
<td>
<%# user.properties[:twitter_handle] %>
<%= user.twitter_handle %>
</td>
<td>
<%# user.properties[:github_username] %>
<%= user.github_username %>
</td>
<td><%= link_to 'Show', user %></td>
<td><%= link_to 'Edit', edit_user_path(user) %></td>
<td><%= link_to 'Destroy', user, method: :delete, data: { confirm: 'Are you sure?' } %></td>
</tr>
<% end %>
</tbody>
</table>