Russian doll caching in Ruby on Rails - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to cache a post partial using Russian doll caching.

Ruby on Rails

<%= cache(@post) do %>
  <%= [1] 'post' %>
<% end %>

Drag options to blanks, or click blank then click option'

Alink_to

Brender

Cform_for

Dcontent_tag

Attempts:

3 left

💡 Hint

Common Mistakes

Using link_to instead of render inside the cache block.

Forgetting to render the partial inside the cache block.

The render method is used inside the cache block to render the post partial, enabling Russian doll caching.

2fill in blank

medium

Complete the code to cache a collection of comments with Russian doll caching.

Ruby on Rails

<%= cache(@comments) do %>
  <%= [1] @comments %>
<% end %>

Drag options to blanks, or click blank then click option'

Aform_for

Blink_to

Crender

Dcontent_tag

Attempts:

3 left

💡 Hint

Common Mistakes

Using link_to or other helpers instead of render.

Not rendering the collection inside the cache block.

Rendering the collection inside the cache block caches each comment efficiently using Russian doll caching.

3fill in blank

hard

Fix the error in the code to properly use Russian doll caching for a post and its comments.

Ruby on Rails

<%= cache(@post) do %>
  <h2><%= [1] %></h2>
  <%= render @post.comments %>
<% end %>

Drag options to blanks, or click blank then click option'

Apost.title

Bpost[:title]

Ctitle

[e-mail]

Attempts:

3 left

💡 Hint

Common Mistakes

Using undefined variable post instead of @post.

Using incorrect syntax like post[:title].

Using @post.title correctly accesses the post's title inside the cache block.

4fill in blank

hard

Fill both blanks to use a cache key with a timestamp for Russian doll caching.

Ruby on Rails

<%= cache([@post, [1]]) do %>
  <%= render 'post', post: @post %>
<% end %>

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[e-mail]_at

[e-mail]_at

[e-mail]

DTime.now

Attempts:

3 left

💡 Hint

Common Mistakes

Using @post.created_at which doesn't change after creation.

Using Time.now which changes every time and breaks caching.

Using @post.updated_at as part of the cache key ensures the cache updates when the post changes.

5fill in blank

hard

Fill all three blanks to implement nested Russian doll caching for a post and its comments.

Ruby on Rails

<%= cache(@post) do %>
  <h1><%= [1] %></h1>
  <ul>
    <% @post.comments.each do |comment| %>
      <li><%= [2](comment) do %>
        <p><%= [3] %></p>
      <% end %></li>
    <% end %>
  </ul>
<% end %>

Drag options to blanks, or click blank then click option'

[e-mail]

Bcache

Ccomment.body

Drender

Attempts:

3 left

💡 Hint

Common Mistakes

Not caching each comment individually.

Using render instead of cache for comments.

Not displaying the comment body correctly.

The post title is shown, each comment is cached with cache(comment), and the comment body is displayed inside.