refactor: simplify a bit the maxLocalTopicBytes validation code

Rather than doing nested diff we simply try to get the max_limit
directly. If we get it means the topic is whitelisted and we check that
value, if not it means the topics is not whitelisted and we raise the
error.

Author: yannrouillard

kp_pre_commit_hooks/gitops_values_validation.py

@@ -1,6 +1,7 @@
 import re
 import sys
 import textwrap
+from collections import defaultdict
 from dataclasses import dataclass, field
 from functools import cache, cached_property
 from pathlib import Path
@@ -49,7 +50,7 @@
 }
 
 # Topics with special max local bytes limits
-WHITELISTED_TOPICS_FOR_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV = {
+ALLOWED_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV = {
     "ais-listener.nmea": {
         "prod": {
             "max_limit": 5_368_709_120,  # 5GB
@@ -449,21 +450,20 @@ def validate_max_local_topic_bytes_compliance(self, value, schema):
             if topic_max_local_bytes is None:
                 continue
 
-            if topic_name in WHITELISTED_TOPICS_FOR_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV:
-                if topic_env in WHITELISTED_TOPICS_FOR_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV[topic_name]:
-                    if topic_max_local_bytes > WHITELISTED_TOPICS_FOR_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV[topic_name][topic_env]["max_limit"]:
-                        yield ValidationError(
-                            f"maxLocalTopicBytes exceeds the allowed maximum of {WHITELISTED_TOPICS_FOR_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV[topic_name][topic_env]['max_limit']} "
-                            f"for topic '{topic_name}' in environment '{topic_env}'.\n"
-                            " See https://kpler.atlassian.net/wiki/x/BgGKS for more information."
-                        )
-                    continue
-
-            yield ValidationError(
-                "maxLocalTopicBytes can only be used with allowed topics"
-                f" and topic '{topic_name}' is not allowed in environment '{topic_env}'."
-                " See https://kpler.atlassian.net/wiki/x/BgGKS for more information."
-            )
+            max_allowed_values = ALLOWED_MAX_LOCAL_TOPIC_BYTES_BY_TOPIC_AND_ENV.get(topic_name, {}).get(topic_env, {}).get("max_limit")
+            if not max_allowed_values:
+                yield ValidationError(
+                    "maxLocalTopicBytes can only be used with allowed topics"
+                    f" and topic '{topic_name}' is not allowed in environment '{topic_env}'."
+                    " See https://kpler.atlassian.net/wiki/x/BgGKS for more information."
+                )
+            elif topic_max_local_bytes > max_allowed_values:
+                yield ValidationError(
+                    f"maxLocalTopicBytes exceeds the allowed maximum of {max_allowed_values} "
+                    f"for topic '{topic_name}' in environment '{topic_env}'.\n"
+                    " See https://kpler.atlassian.net/wiki/x/BgGKS for more information."
+                )
+
 
     def validate_forbidden_environment_variables(self, value, schema):
         if not isinstance(value, dict):