External image

The external_image field displays an image from a URL stored in the database or returned by a computed field. It renders the image on the Index and Show views, and provides a text input for the URL on forms.

# app/avo/resources/company.rb
field :logo, as: :external_image

By default, the image has a height of 40 pixels, square corners, and no link to the record. Blank values render no image. On Show, images also have a maximum width of 340 pixels.

Adjust the image for each view

Set height and radius to change the image size and rounded corners. Use procs when the Index and Show views need different styling:

# app/avo/resources/company.rb
field :logo, as: :external_image,
  height: -> { view.index? ? 40 : 150 },
  radius: -> { view.index? ? 4 : 12 }

These procs run in Avo's execution context, with access to record, resource, view, and field.

Width behavior

The field accepts width, but the standard Index and Show image templates do not apply it. Set the height to resize the image; do not rely on width to produce a square thumbnail.

Open the record from an image

Enable link_to_record to make the Index image a link to the record. It does not add a link on Show.

# app/avo/resources/company.rb
field :logo, as: :external_image, link_to_record: true

Use computed values

Another common scenario is to use a value from your database and create a new URL using a computed value.

# app/avo/resources/company.rb
field :logo, as: :external_image do
  "//logo.clearbit.com/#{URI.parse(record.url).host}?size=180"
rescue
  nil
end

Show the image on grid cards

For a grid view, set the card's cover_url to the image URL. Grid covers are configured separately from the field's sizing options.

# app/avo/resources/company.rb
self.grid_view = {
  card: -> do
    {
      cover_url: "//logo.clearbit.com/#{URI.parse(record.url).host}?size=180",
      title: record.name
    }
  rescue
    { cover_url: nil, title: record.name }
  end
}

Reference and shared options

See the External image API for field-specific contracts and common field options for settings shared with other fields.