[aws][feat] Add region_in_use property for region (#2086)

Author: aquamatthias

plugins/aws/fix_plugin_aws/collector.py

@@ -237,6 +237,11 @@ def get_last_run() -> Optional[datetime]:
                     log.warning(f"Unexpected node type {node} in graph")
                     raise Exception("Only AWS resources expected")
 
+            # final hook when the graph is complete
+            for node, data in list(self.graph.nodes(data=True)):
+                if isinstance(node, AwsResource):
+                    node.complete_graph(global_builder, data.get("source", {}))
+
             # wait for all futures to finish
             shared_queue.wait_for_submitted_work()
             self.core_feedback.progress_done(self.account.dname, 1, 1, context=[self.cloud.id])

plugins/aws/fix_plugin_aws/resource/base.py

@@ -11,7 +11,7 @@
 
 from math import ceil
 
-from attr import evolve
+from attr import evolve, field
 from attrs import define
 from boto3.exceptions import Boto3Error
 
@@ -28,6 +28,7 @@
     Cloud,
     EdgeType,
     ModelReference,
+    PhantomBaseResource,
 )
 from fixlib.config import Config, current_config
 from fixlib.core.actions import CoreFeedback, SuppressWithFeedback
@@ -257,11 +258,15 @@ def called_mutator_apis(cls) -> List[AwsApiSpec]:
         return []
 
     def post_process(self, builder: GraphBuilder, source: Json) -> None:
-        # Default behavior: do nothing
+        # Hook method: called after the resource has been created and added to the graph.
         pass
 
     def connect_in_graph(self, builder: GraphBuilder, source: Json) -> None:
-        # Default behavior: add resource to the namespace
+        # Hook method: called when all resources are collected.
+        pass
+
+    def complete_graph(self, builder: GraphBuilder, source: Json) -> None:
+        # Hook that is called when all resources have been collected and connected.
         pass
 
     def __str__(self) -> str:
@@ -368,13 +373,27 @@ class AwsRegion(BaseRegion, AwsResource):
         }
     }
     ctime: Optional[datetime] = default_ctime
+    region_in_use: Optional[bool] = field(default=None, metadata={"description": "Indicates if the region is in use."})
 
     def __attrs_post_init__(self) -> None:
         super().__attrs_post_init__()
         self.long_name = cloud_region_data.get("aws", {}).get(self.id, {}).get("long_name")
         self.latitude = cloud_region_data.get("aws", {}).get(self.id, {}).get("latitude")
         self.longitude = cloud_region_data.get("aws", {}).get(self.id, {}).get("longitude")
 
+    def complete_graph(self, builder: GraphBuilder, source: Json) -> None:
+        count = 0
+        # A region with less than 10 real resources is considered not in use.
+        # AWS is creating a couple of resources in every region automatically.
+        # The number 10 is chosen by looking into different empty regions.
+        empty_region = 10
+        for succ in builder.graph.descendants(self):
+            if not isinstance(succ, PhantomBaseResource):
+                count += 1
+                if count > empty_region:
+                    break
+        self.region_in_use = count > empty_region
+
 
 @define(eq=False, slots=False)
 class AwsEc2VolumeType(AwsResource, BaseVolumeType):

plugins/aws/test/collector_test.py

@@ -11,7 +11,7 @@
     called_collect_apis,
     called_mutator_apis,
 )
-from fix_plugin_aws.resource.base import AwsResource, AwsApiSpec, GraphBuilder
+from fix_plugin_aws.resource.base import AwsResource, AwsApiSpec, GraphBuilder, AwsRegion
 from fix_plugin_aws.resource.ec2 import AwsEc2Instance
 from fixlib.core.model_export import dataclasses_to_fixcore_model
 from test import account_collector, builder, aws_client, aws_config, no_feedback  # noqa: F401
@@ -36,6 +36,9 @@ def count_kind(clazz: Type[AwsResource]) -> int:
     assert count_kind(AwsResource) == 226
     assert len(account_collector.graph.edges) == 516
     assert len(account_collector.graph.deferred_edges) == 2
+    for node in account_collector.graph.nodes:
+        if isinstance(node, AwsRegion):
+            assert node.region_in_use
 
 
 def test_dependencies() -> None: