Closes #9416: Dashboard widgets (#11823)

* Replace masonry with gridstack

* Initial work on dashboard widgets

* Implement function to save dashboard layout

* Define a default dashboard

* Clean up widgets

* Implement widget configuration views & forms

* Permit merging dict value with existing dict in user config

* Add widget deletion view

* Enable HTMX for widget configuration

* Implement view to add dashboard widgets

* ObjectCountsWidget: Identify models by app_label & name

* Add color customization to dashboard widgets

* Introduce Dashboard model to store user dashboard layout & config

* Clean up utility functions

* Remove hard-coded API URL

* Use fixed grid cell height

* Add modal close button

* Clean up dashboard views

* Rebuild JS

netbox/extras/models/__init__.py

@@ -1,6 +1,7 @@
 from .change_logging import ObjectChange
 from .configs import *
 from .customfields import CustomField
+from .dashboard import *
 from .models import *
 from .search import *
 from .staging import *
@@ -15,6 +16,7 @@ __all__ = (
     'ConfigTemplate',
     'CustomField',
     'CustomLink',
+    'Dashboard',
     'ExportTemplate',
     'ImageAttachment',
     'JobResult',

netbox/extras/models/dashboard.py

@@ -0,0 +1,70 @@
+from django.contrib.auth import get_user_model
+from django.db import models
+
+from extras.dashboard.utils import get_widget_class
+
+__all__ = (
+    'Dashboard',
+)
+
+
+class Dashboard(models.Model):
+    user = models.OneToOneField(
+        to=get_user_model(),
+        on_delete=models.CASCADE,
+        related_name='dashboard'
+    )
+    layout = models.JSONField()
+    config = models.JSONField()
+
+    class Meta:
+        pass
+
+    def get_widget(self, id):
+        """
+        Instantiate and return a widget by its ID
+        """
+        id = str(id)
+        config = dict(self.config[id])  # Copy to avoid mutating instance data
+        widget_class = get_widget_class(config.pop('class'))
+        return widget_class(id=id, **config)
+
+    def get_layout(self):
+        """
+        Return the dashboard's configured layout, suitable for rendering with gridstack.js.
+        """
+        widgets = []
+        for grid_item in self.layout:
+            widget = self.get_widget(grid_item['id'])
+            widget.set_layout(grid_item)
+            widgets.append(widget)
+        return widgets
+
+    def add_widget(self, widget, x=None, y=None):
+        """
+        Add a widget to the dashboard, optionally specifying its X & Y coordinates.
+        """
+        id = str(widget.id)
+        self.config[id] = {
+            'class': widget.name,
+            'title': widget.title,
+            'color': widget.color,
+            'config': widget.config,
+        }
+        self.layout.append({
+            'id': id,
+            'h': widget.height,
+            'w': widget.width,
+            'x': x,
+            'y': y,
+        })
+
+    def delete_widget(self, id):
+        """
+        Delete a widget from the dashboard.
+        """
+        id = str(id)
+        del self.config[id]
+        self.layout = [
+            item for item in self.layout if item['id'] != id
+        ]