Accessing yaml data array value by name

#1

Hello,

On my site, I have a group of projects that I list out on a ‘projects’ page. Each project then has its own individual page, with a shared template.

The data structure is:

data/projects.yml

project_one
  title:
    "Project One"
  description:
    "Description of project one"
  year:
    2018

project_two
  title:
    "Project Two"
  description:
    "Description of project two"
  year:
    2018

I then manually list each project on the ‘projects’ page, and reuse the data on an individual page, both with:

<%= data.projects.project_two.title %>

This works at the moment, but it doesn’t scale well and any changes made to a project’s markup in the list has to be duplicated throughout the page.

I can easily change this to an array and loop through it, e.g.

data/projects.yml

- project_one
  title:
    "Project One"
  description:
    "Description of project one"
  year:
    2018

- project_two
  title:
    "Project Two"
  description:
    "Description of project two"
  year:
    2018

  <% unless data.work.nil? %>
    <ul>
      <% data.work.each do |f| %>
      <li>
        <h2><%= f.title %></h2>
        <p><%= f.description %></p>
      </li>
      <% end %>
    </ul>
  <% end %>

I’d then like to access specific project values for each project page, so, for example, if I have project-one.html.erb, I can display the title from the array.

I know this is possible with

  <%= data.work[0].title %>
  <%= data.work[0].description %>

But is it possible to access the hash value by key name? I’ve read a number of posts on the forum, and referenced some Ruby docs, and have seen references to something like:

  <%= data.work['project_two']['title'] %>

but that returns a no implicit conversion of String into Integer error, as I imagine its expecting an array integer. I have a basic understanding of Ruby methods but not certain what applies here.

The docs mention something similar using a proxy and auto-generated pages, but each of my project pages are heavily customized so generating on build isn’t an option. Alternatively, I’ve looked at building each project as a yaml file in a subdirectory (data/projects/project-one.yml) and then accessing them individually, both I’m not sure it’s feasible to loop through and output the subdirectories on an index page.

Thanks for any tips

#2

Did you try the instance_eval function yet?

You should be able to keep the first version of your .yml file and access the fields with:

<%= data.projects.instance_eval('project_two').title %>
#3

Thanks for the tip. While it does work with the first example, i.e. I can pull out the title on any given page like:

project_one
  title:
    "Project One"
  description:
    "Description of project one"
  year:
    2018

project_two
  title:
    "Project Two"
  description:
    "Description of project two"
  year:
    2018

<%= data.projects.instance_eval('project_two').year %>

But unfortunately I can’t iterate through a loop of that yaml data, e.g.

<% unless data.projects.nil? %>
  <% data.projects.each do |f| %>
    <%= f.title %>
  <% end %>
<% end %>

Using the second yaml example from my original post, I can iterate through a loop but I can’t access individual data.

(As an aside, isn’t instance_eval doing the same as <%= data.projects.project_two.year %> ?)

#4

This Is exactly what I have been trying to accomplish. I have roughly 20 thousand pages I am trying to dynamically create from a data file. I know too that this is possible, however I’m new to middleman and Ruby.

Has any progress been made on this? I will keep looking, and hopefully find something soon.

I’ll repost with an answer if I find something.