feat: Add optional ordering feature for resources

Implemented optional ordering of resources in FastAPI admin. Code has been added to accept an 'order_by' parameter in the resource route, if present the list of resources will be sorted accordingly. Templates were updated to support this feature by adding a clickable link to each column header for sorting.

fastapi_admin/routes/resources.py

@@ -1,3 +1,5 @@
+from typing import Optional
+
 from fastapi import APIRouter, Depends, Path
 from jinja2 import TemplateNotFound
 from starlette.requests import Request
@@ -25,6 +27,7 @@ async def list_view(
     resource: str = Path(...),
     page_size: int = 10,
     page_num: int = 1,
+    order_by: Optional[str] = None,
 ):
     fields_label = model_resource.get_fields_label()
     fields = model_resource.get_fields()
@@ -33,6 +36,8 @@ async def list_view(
     params, qs = await model_resource.resolve_query_params(request, dict(request.query_params), qs)
     filters = await model_resource.get_filters(request, params)
     total = await qs.count()
+    if order_by:
+        qs = qs.order_by(order_by)
     if page_size:
         qs = qs.limit(page_size)
     else:

fastapi_admin/templates/list.html

@@ -88,8 +88,22 @@
                                 />
                             </th>
                         {% endif %}
-                        {% for label in fields_label %}
-                            <th>{{ label }}</th>
+                        {% for field in fields %}
+                            <th {% for k,v in column_attributes[loop.index0].items() %}{{ k }}="{{ v }}"{% endfor %}>
+                            {% set current_order = request.query_params.get('order_by', '') %}
+                            {% set is_desc = current_order.startswith('-') %}
+                            {% if current_order.lstrip('-') == field.name %}
+                                {% set order_by = '-' + field.name if not is_desc else field.name %}
+                            {% else %}
+                                {% set order_by = field.name %}
+                            {% endif %}
+                            <a href="{{ request.url.include_query_params(order_by=order_by) }}">
+                                {{ field.label }}
+                                {% if current_order.lstrip('-') == field.name %}
+                                    {% if is_desc %}&#x25BC;{% else %}&#x25B2;{% endif %}
+                                {% endif %}
+                            </a>
+                            </th>
                         {% endfor %}
                         {% if model_resource.actions %}
                             <th></th>