Ordering

You can configure the ordering of the resource index page. By default, resources are ordered in ascending order by the LiveResource's configured primary_key (:id unless you override it).

Configuration

To configure the ordering of the resource index page, use the init_order option in your resource configuration file. This option accepts either a map or a function that returns a map.

The map must contain the following keys:

• :by - The field to order by (atom)
• :direction - The order direction (:asc for ascending or :desc for descending)

Using a Map

You can directly specify the ordering with a map:

# in your resource configuration file (live resource)
use Backpex.LiveResource,
  # ...other options
  init_order: %{by: :inserted_at, direction: :desc}

This configuration orders resources by the inserted_at field in descending order.

Using a Function

# in your resource configuration file (live resource)
use Backpex.LiveResource,
  # ...other options
  init_order: &__MODULE__.init_order/1

def init_order(_assigns) do
  %{by: :username, direction: :asc}
end

The function must:

• Take one argument (assigns)
• Return a map with :by and :direction keys

This approach allows you to determine the ordering based on runtime conditions or user-specific data in assigns.

URL Parameters

Users can change the ordering through URL parameters:

• order_by - The field to order by (must match an orderable field name)
• order_direction - Either asc or desc

For example: /admin/posts?order_by=title&order_direction=desc

Validation

Backpex validates ordering parameters from the URL:

Invalid URL parameters won't crash the application. Instead, they are silently replaced with the default values from your init_order configuration.

Disabling Ordering for Fields

By default, all fields are orderable. To disable ordering for a specific field, set orderable: false in the field configuration:

@impl Backpex.LiveResource
def fields do
  [
    title: %{
      module: Backpex.Fields.Text,
      label: "Title"
    },
    body: %{
      module: Backpex.Fields.Textarea,
      label: "Body",
      orderable: false  # Users cannot order by this field
    }
  ]
end