Middleman > Retrieve fields values

Once you have obtained a record object, you can access the value associated to a field using its Field ID:

In this case, the field ID is title, so we can use it as a method on the record object to retrieve its value:

blog_post = dato.blog_posts.first     # get the first blog post of the collection
blog_post.title                       # => "Hello world!"

Each record also exposes some additional methods you can use:

blog_post.id                  # returns the record ID:
                              # => "1242"
blog_post.item_type           # returns an object representing the model:
blog_post.item_type.id        # => "44"
blog_post.item_type.name      # => "Blog post"
blog_post.item_type.api_key   # => "blog_post"
blog_post.updated_at          # returns last modified date:
                              # => <Time value="2017-01-24 10:41:55 +0100">
blog_post.position            # returns its ordinal number in the collection
                              # (only if the model is sortable or a tree):
                              #
                              # => 13
blog_post.parent              # returns the parent record (only if the model is a tree)
blog_post.children            # returns the children records (only if the model is a tree)
blog_post.to_hash             # returns an hash containing the above, plus all the
                              # fields's values:
                              #
                              # => {
                              #   id: "1242",
                              #   item_type: "blog_post",
                              #   updated_at: <Time value="2017-01-24 10:41:55 +0100">,
                              #   title: "Hello world!",
                              #   ...
                              # }

Most field types return scalar values (integers, booleans, strings, etc.), but some other return more complex structures.

Keep in mind that the .toMap() method will limit the results to a maximum depth of 3. You can change this setting passing an explicit depth:

blog_post.to_hash(10)   // this will go down 10 levels deep!

Single file fields

File fields expose the following methods. The .url() method is the most important one, as it returns the full URL of the file.

blog_post.cover_image.url         # returns the file URL:
                                  # => "https://www.datocms-assets.com/123/12345-heart.png"
blog_post.cover_image.url(        # returns the image URL, cropped at 150x150px:
  w: 150,                         # => "https://www.datocms-assets.com/123/12345-heart.png?w=150&h=150&fit=crop"
  h: 150,
  fit: "crop",
)
blog_post.cover_image.size         # returns the filesize in bytes:
                                   # => 168131
blog_post.cover_image.format       # returns the extension:
                                   # => "png"
blog_post.cover_image.width        # returns the image width:
                                   # => 800
blog_post.cover_image.height       # returns the image height:
                                   # => 600
blog_post.cover_image.alt          # returns the asset alternative text:
                                   # => "Heart icon"
blog_post.cover_image.title        # returns the asset title:
                                   # => "We love our clients"
blog_post.cover_image.custom_data  # returns any asset custom data:
                                   # => { "watermark": true }
blog_post.cover_image.focal_point  # returns asset focal point:
                                   # => { x: 0.4, y: 0.6 }
blog_post.cover_image.author       # returns the asset author:
                                   # => "Mark Smith"
blog_post.cover_image.copyright    # returns the asset copyright:
                                   # => "PressNews Inc."
blog_post.cover_image.notes        # returns the asset's notes:
                                   # => "Just a beautiful heart image"
blog_post.cover_image.to_hash      # returns an hash containing all the above:
                                   #
                                   # => {
                                   #   size: 168131,
                                   #   format: "png",
                                   #   width: 800,
                                   #   height: 600,
                                   #   url: "https://www.datocms-assets.com/123/12345-heart.png"
                                   # }
blog_post.cover_image.lqip_data_url(      # returns a blurred-up SVG of the asset:
  w: 800, h: 600, fm: :jpg         #
)                                  # => "data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wCEAAoHBwgHBgoICAgXFQoLDhUSDhUXDh0eDRUVGRYZGBYTFhUaIi0jGh0oHRUWJDUlKC0vMjIyGSI4PTcwPCsxMi8BCgsLDg0OHBAQHDsoIig7Lzs7Ozs7Ozs7LzsvLy8vLy8vLzsvLy8vLy8vLy8vLy8vLy8vLy8vLy8vLy8vLy8vL//AABEIAA0AGAMBIgACEQEDEQH/xAAYAAEAAwEAAAAAAAAAAAAAAAAAAwQFAv/EABwQAAAHAQEAAAAAAAAAAAAAAAABAgMEBRESQf/EABUBAQEAAAAAAAAAAAAAAAAAAAMB/8QAHREAAQMFAQAAAAAAAAAAAAAAAQAREgITITFCA//aAAwDAQACEQMRAD8AqPMJiF1o6jvlILkhlWU11aMMTU6j50UPHKcCmTJa1aXEnvoBdy3GmTNPgAwfTkpbNJ2F/9k="

Multiple files fields

Multiple files fields simply return an array of file objects:

blog_post.gallery.each do |image|
  image.title   # => "We love our clients"
  image.url     # => "https://www.datocms-assets.com/123/12345-heart.png"
end

Color fields

Color fields expose the following methods:

blog_post.color.red        # => 255
blog_post.color.green      # => 127
blog_post.color.blue       # => 0
blog_post.color.alpha      # => 1.0
blog_post.color.rgb        # => "rgb(255, 127, 0)"
blog_post.color.hex        # => "#ff7f00"
blog_post.color.to_hash    # => {
                           #  red: 255,
                           #  green: 127,
                           #  blue: 0,
                           #  alpha: 1.0,
                           #  rgb: "rgb(255, 127, 0)",
                           #  hex: "#ff7f00"
                           # }

Geolocation fields

Geolocation fields expose the following methods:

blog_post.position.latitude    # => 41.90278349999999
blog_post.position.longitude   # => 12.496365500000024
blog_post.position.to_hash     # => {
                               #  latitude: 41.90278349999999,
                               #  longitude: 12.496365500000024
                               # }

Video fields

Video fields expose the following methods:

blog_post.video.title          # => "Nyan Cat"
blog_post.video.url            # => "https://www.youtube.com/watch?v=QH2-TGUlwu4&t=11s"
blog_post.video.thumbnail_url  # => "https://i.ytimg.com/vi/QH2-TGUlwu4/hqdefault.jpg"
blog_post.video.provider       # => "youtube"
blog_post.video.provider_uid   # => "QH2-TGUlwu4"
blog_post.video.height         # => 344
blog_post.video.width          # => 459
blog_post.video.to_hash        # => {
                               #  title: "Nyan Cat",
                               #  url: "https://www.youtube.com/watch?v=QH2-TGUlwu4&t=11s",
                               #  thumbnail_url: "https://i.ytimg.com/vi/QH2-TGUlwu4/hqdefault.jpg",
                               #  provider: "youtube",
                               #  provider_uid: "QH2-TGUlwu4",
                               #  height: 344,
                               #  width: 459
                               # }

SEO meta tags fields

SEO meta tags fields expose the following methods (although it's far easier to generate SEO meta tags using the .seo_meta_tags method:

blog_post.seo.title         # => "Article title"
blog_post.seo.description   # => "Lorem ipsum dolor sit amet, consectetur..."
blog_post.seo.image         # => returns a full image object (see `Media fields` chapter)
blog_post.seo.to_hash       # => {
                            #   title: "Article title",
                            #   description: "Lorem ipsum dolor sit amet, consectetur...",
                            #   image: {
                            #     size: 168131,
                            #     format: "png",
                            #     width: 800,
                            #     height: 600,
                            #     url: "https://www.datocms-assets.com/123/12345-heart.png"
                            #   }
                            # }

Tree-like collections

If you have tree-like collections you can use the .children and .parent attributes to find the top-level objects of the collection and then navigate in depth:

def traverse(records, depth = 0, &block)
  records.each do |record|
    block.call(record, depth)
    traverse(record.children, depth + 1, &block);
  end
end
root_categories = dato.categories.select do |category|
  !category.parent
end
traverse(root_categories) do |category, depth|
  puts "  " * depth  + "* #{category.name}"
end

This will output something similar to this:

* Tote Panniers
  * Handlebar bag
  * Backpacks and Rucksacks
* Double Panniers
  * Satchel