Render ControlPlane.api_credentials in admin as separate fields

src/servala/core/admin.py

@@ -1,6 +1,7 @@
 from django.contrib import admin
 from django.utils.translation import gettext_lazy as _
 
+from servala.core.forms import ControlPlaneAdminForm
 from servala.core.models import (
     BillingEntity,
     CloudProvider,
@@ -110,11 +111,32 @@ class CloudProviderAdmin(admin.ModelAdmin):
 
 @admin.register(ControlPlane)
 class ControlPlaneAdmin(admin.ModelAdmin):
+    form = ControlPlaneAdminForm
     list_display = ("name", "cloud_provider", "k8s_api_endpoint")
     list_filter = ("cloud_provider",)
     search_fields = ("name", "description", "k8s_api_endpoint")
     autocomplete_fields = ("cloud_provider",)
 
+    fieldsets = (
+        (
+            None,
+            {"fields": ("name", "description", "k8s_api_endpoint", "cloud_provider")},
+        ),
+        (
+            _("API Credentials"),
+            {
+                "fields": ("certificate_authority_data", "server", "token"),
+                "description": _(
+                    "All three credential fields must be provided together or left empty."
+                ),
+            },
+        ),
+    )
+
+    def get_exclude(self, request, obj=None):
+        # Exclude the original api_credentials field as we're using our custom fields
+        return ["api_credentials"]
+
 
 @admin.register(Plan)
 class PlanAdmin(admin.ModelAdmin):

src/servala/core/forms.py

@@ -0,0 +1,77 @@
+from django import forms
+from django.core.exceptions import ValidationError
+from django.utils.translation import gettext_lazy as _
+
+from servala.core.models import ControlPlane
+
+
+class ControlPlaneAdminForm(forms.ModelForm):
+    certificate_authority_data = forms.CharField(
+        widget=forms.Textarea,
+        required=False,
+        help_text=_("Certificate authority data for the Kubernetes API"),
+    )
+    server = forms.URLField(
+        required=False,
+        help_text=_("Server URL for the Kubernetes API"),
+    )
+    token = forms.CharField(
+        widget=forms.Textarea,
+        required=False,
+        help_text=_("Authentication token for the Kubernetes API"),
+    )
+
+    class Meta:
+        model = ControlPlane
+        fields = "__all__"
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        # If we have existing api_credentials, populate the individual fields
+        if self.instance.pk and self.instance.api_credentials:
+            creds = self.instance.api_credentials
+            self.fields["certificate_authority_data"].initial = creds.get(
+                "certificate-authority-data", ""
+            )
+            self.fields["server"].initial = creds.get("server", "")
+            self.fields["token"].initial = creds.get("token", "")
+
+    def clean(self):
+        cleaned_data = super().clean()
+
+        # Get the three credential fields
+        ca_data = cleaned_data.get("certificate_authority_data")
+        server = cleaned_data.get("server")
+        token = cleaned_data.get("token")
+
+        # Check if any of the fields are filled
+        has_ca = bool(ca_data)
+        has_server = bool(server)
+        has_token = bool(token)
+
+        # If some but not all fields are filled, raise validation error
+        if (has_ca or has_server or has_token) and not (
+            has_ca and has_server and has_token
+        ):
+            raise ValidationError(
+                _(
+                    "All credential fields (certificate authority data, server, and token) must be provided together or left empty."
+                )
+            )
+
+        # If all fields are filled, create the api_credentials JSON
+        if has_ca and has_server and has_token:
+            cleaned_data["api_credentials"] = {
+                "certificate-authority-data": ca_data,
+                "server": server,
+                "token": token,
+            }
+        else:
+            cleaned_data["api_credentials"] = {}
+
+        return cleaned_data
+
+    def save(self, *args, **kwargs):
+        self.instance.api_credentials = self.cleaned_data["api_credentials"]
+        return super().save(*args, **kwargs)

src/servala/core/models/service.py

@@ -68,7 +68,10 @@ class ControlPlane(models.Model):
     description = models.TextField(blank=True, verbose_name=_("Description"))
     k8s_api_endpoint = models.URLField(verbose_name=_("Kubernetes API endpoint"))
     # TODO: schema
-    api_credentials = EncryptedJSONField(verbose_name=_("API credentials"))
+    api_credentials = EncryptedJSONField(
+        verbose_name=_("API credentials"),
+        help_text="Required fields: certificate-authority-data, server (URL), token",
+    )
 
     cloud_provider = models.ForeignKey(
         to="CloudProvider",