Refactor dashboard data serialization and mock context for improved clarity

- Introduced `serialize_audit_for_response` and `serialize_current_cluster_for_template` functions to handle JSON serialization of audit and cluster data, enhancing data consistency for API responses and template rendering.
- Updated `get_mock_context` in `mock_data.py` to utilize the new serialization functions, simplifying the mock data structure and improving readability.
- Refactored `collect_context` and `collect_audits` in `views.py` to leverage the new serialization methods, ensuring a cleaner and more maintainable codebase.
- Added unit tests for the new serialization functions to ensure correctness and reliability of data formatting.

dashboard/openstack_utils/audits.py

@@ -49,41 +49,81 @@ def get_current_cluster_cpu(connection: Connection) -> dict:
     }
 
 
+def _fetch_audits_and_action_plans(session, watcher_endpoint):
+    """GET audits and action_plans from Watcher API. Returns (audits_list, action_plans_list)."""
+    audits_resp = session.get(f"{watcher_endpoint}/v1/audits")
+    audits_resp.raise_for_status()
+    audits_list = audits_resp.json().get("audits") or []
+
+    actionplans_resp = session.get(f"{watcher_endpoint}/v1/action_plans")
+    actionplans_resp.raise_for_status()
+    action_plans_list = actionplans_resp.json().get("action_plans") or []
+
+    return audits_list, action_plans_list
+
+
+def _fetch_migrations_for_audit(
+    connection, session, watcher_endpoint, audit_resp, actionplan, actions_resp
+):
+    """
+    Fetch action details for the given action plan and build migrations list and
+    instance->destination mapping. Returns (migrations, mapping).
+    """
+    migrations = []
+    mapping = {}
+    for action in actions_resp:
+        action_resp = session.get(f"{watcher_endpoint}/v1/actions/{action['uuid']}")
+        action_resp.raise_for_status()
+        action_resp = action_resp.json()
+
+        server = connection.get_server_by_id(action_resp["input_parameters"]["resource_id"])
+        params = action_resp["input_parameters"]
+        mapping[params["resource_name"]] = params["destination_node"]
+
+        migrations.append(
+            {
+                "instanceName": params["resource_name"],
+                "source": params["source_node"],
+                "destination": params["destination_node"],
+                "flavor": server.flavor.name,
+                "impact": "Low",
+            }
+        )
+    return migrations, mapping
+
+
+def _build_projected_cpu_metrics(cpu_data, mapping):
+    """
+    Apply instance->destination mapping to a copy of cpu_data and return
+    aggregated CPU metrics DataFrame (host, cpu_usage).
+    """
+    projected_cpu_data = copy(cpu_data)
+    for entry in projected_cpu_data:
+        if (instance := entry["metric"]["instanceName"]) in mapping:
+            entry["metric"]["host"] = mapping[instance]
+    return convert_cpu_data(projected_cpu_data)
+
+
 def get_audits(connection: Connection) -> list[dict] | None:
     session = connection.session
-
     watcher_endpoint = connection.endpoint_for(
         service_type=WATCHER_ENDPOINT_NAME, interface=WATCHER_INTERFACE_NAME
     )
 
-    # Collect instances prometheus metrics
     cpu_data = query_prometheus(PROMETHEUS_METRICS["cpu_usage"])
-
     cpu_metrics = convert_cpu_data(data=cpu_data)
 
-    # Fetch audit list
-    audits_resp = session.get(f"{watcher_endpoint}/v1/audits")
-    audits_resp.raise_for_status()
-    audits_resp = audits_resp.json().get("audits") or []
-
-    # Fetch action plan list
-    actionplans_resp = session.get(f"{watcher_endpoint}/v1/action_plans")
-    actionplans_resp.raise_for_status()
-    actionplans_resp = actionplans_resp.json().get("action_plans") or []
-
-    # Filtering audits by PENDING state
-    pending_audits = [plan for plan in actionplans_resp if plan["state"] == "RECOMMENDED"]
+    _, action_plans_list = _fetch_audits_and_action_plans(session, watcher_endpoint)
+    pending_audits = [plan for plan in action_plans_list if plan["state"] == "RECOMMENDED"]
 
     result = []
     for item in pending_audits:
-        projected_cpu_data = copy(cpu_data)
-
         audit_resp = session.get(f"{watcher_endpoint}/v1/audits/{item['audit_uuid']}")
         audit_resp.raise_for_status()
         audit_resp = audit_resp.json()
 
         actionplan = next(
-            filter(lambda x: x.get("audit_uuid") == audit_resp["uuid"], actionplans_resp), None
+            filter(lambda x: x.get("audit_uuid") == audit_resp["uuid"], action_plans_list), None
         )
         if actionplan is None:
             continue
@@ -94,32 +134,10 @@ def get_audits(connection: Connection) -> list[dict] | None:
         actions_resp.raise_for_status()
         actions_resp = actions_resp.json().get("actions") or []
 
-        migrations = []
-        mapping = {}
-        for action in actions_resp:
-            action_resp = session.get(f"{watcher_endpoint}/v1/actions/{action['uuid']}")
-            action_resp.raise_for_status()
-            action_resp = action_resp.json()
-
-            server = connection.get_server_by_id(action_resp["input_parameters"]["resource_id"])
-            params = action_resp["input_parameters"]
-            mapping[params["resource_name"]] = params["destination_node"]
-
-            migrations.append(
-                {
-                    "instanceName": action_resp["input_parameters"]["resource_name"],
-                    "source": action_resp["input_parameters"]["source_node"],
-                    "destination": action_resp["input_parameters"]["destination_node"],
-                    "flavor": server.flavor.name,
-                    "impact": "Low",
-                }
-            )
-
-        for entry in projected_cpu_data:
-            if (instance := entry["metric"]["instanceName"]) in mapping:
-                entry["metric"]["host"] = mapping[instance]
-
-        projected_cpu_metrics = convert_cpu_data(projected_cpu_data)
+        migrations, mapping = _fetch_migrations_for_audit(
+            connection, session, watcher_endpoint, audit_resp, actionplan, actions_resp
+        )
+        projected_cpu_metrics = _build_projected_cpu_metrics(cpu_data, mapping)
 
         result.append(
             {