add parameters system to the rule model

Signed-off-by: tdruez <tdruez@aboutcode.org>

Author: tdruez

policy/admin.py

@@ -28,6 +28,7 @@
 from policy.models import AssociatedPolicy
 from policy.models import PolicyRule
 from policy.models import UsagePolicy
+from policy.rules import RULE_REGISTRY
 
 License = apps.get_model("license_library", "license")
 
@@ -168,6 +169,7 @@ class PolicyRuleAdmin(DataspacedAdmin):
     form = PolicyRuleForm
     list_display = ("name", "rule_type", "threshold", "is_active", "event_name", "get_dataspace")
     list_filter = DataspacedAdmin.list_filter + ("rule_type", "is_active")
+    readonly_fields = DataspacedAdmin.readonly_fields + ("parameters_schema_hint",)
     activity_log = False
     actions = []
     actions_to_remove = ["copy_to", "compare_with"]
@@ -186,3 +188,12 @@ class PolicyRuleAdmin(DataspacedAdmin):
         "threshold (0 means any violation triggers the rule), and provide an event name "
         "to send a webhook notification when violations are detected or resolved."
     )
+
+    def parameters_schema_hint(self, obj):
+        handler = RULE_REGISTRY.get(obj.rule_type)
+        if not handler or not handler.parameters_schema:
+            return "No parameters supported for this rule type."
+        lines = [f"{key}: {desc}" for key, desc in handler.parameters_schema.items()]
+        return mark_safe("<br>".join(lines))
+
+    parameters_schema_hint.short_description = "Supported parameters"

policy/migrations/0003_policyrule.py

@@ -24,6 +24,7 @@ class Migration(migrations.Migration):
                 ('threshold', models.PositiveIntegerField(default=0, help_text='Minimum number of violations required to trigger this rule (0 means any).')),
                 ('is_active', models.BooleanField(default=True, help_text='Only active rules are evaluated.')),
                 ('event_name', models.CharField(blank=True, help_text='Notification event to fire when violations are detected.', max_length=100)),
+                ('parameters', models.JSONField(blank=True, default=dict, help_text='Optional rule-specific parameters as a JSON object. Supported keys depend on the chosen rule type.')),
                 ('dataspace', models.ForeignKey(editable=False, help_text='A Dataspace is an independent, exclusive set of DejaCode data, which can be either nexB master reference data or installation-specific data.', on_delete=django.db.models.deletion.PROTECT, to='dje.dataspace')),
             ],
             options={

policy/models.py

@@ -273,6 +273,14 @@ class PolicyRule(DataspacedModel):
         blank=True,
         help_text=_("Notification event to fire when violations are detected."),
     )
+    parameters = models.JSONField(
+        blank=True,
+        default=dict,
+        help_text=_(
+            "Optional rule-specific parameters as a JSON object. "
+            "Supported keys depend on the chosen rule type."
+        ),
+    )
 
     objects = PolicyRuleQuerySet.as_manager()