Ordering

You can configure the ordering of the resource index page. By default, the resources are ordered by the id field in ascending order.

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