Implement list_topics, describe_topics, and describe_cluster

Author: Tyler Lubeck

kafka/admin/client.py

@@ -472,14 +472,48 @@ def delete_topics(self, topics, timeout_ms=None):
                 .format(version))
         return response
 
-    # list topics functionality is in ClusterMetadata
-    # Note: if implemented here, send the request to the least_loaded_node()
 
-    # describe topics functionality is in ClusterMetadata
-    # Note: if implemented here, send the request to the controller
+    def _get_cluster_metadata(self, topics=None, auto_topic_creation=False):
+        """
+        topics == None means "get all topics"
+        """
+        version = self._matching_api_version(MetadataRequest)
+        if version <= 3:
+            if auto_topic_creation:
+                raise IncompatibleBrokerVersion(
+                    "auto_topic_creation requires MetadataRequest >= v4, which"
+                    " is not supported by Kafka {}"
+                    .format(self.config['api_version']))
 
-    # describe cluster functionality is in ClusterMetadata
-    # Note: if implemented here, send the request to the least_loaded_node()
+            request = MetadataRequest[version](topics=topics)
+        elif version <= 5:
+            request = MetadataRequest[version](
+                topics=topics,
+                allow_auto_topic_creation=auto_topic_creation
+            )
+
+        future = self._send_request_to_node(
+            self._client.least_loaded_node(),
+            request
+        )
+        self._wait_for_futures([future])
+        return future.value
+
+    def list_topics(self):
+        metadata = self._get_cluster_metadata(topics=None)
+        obj = metadata.to_object()
+        return [t['topic'] for t in obj['topics']]
+
+    def describe_topics(self, topics=None):
+        metadata = self._get_cluster_metadata(topics=topics)
+        obj = metadata.to_object()
+        return obj['topics']
+
+    def describe_cluster(self):
+        metadata = self._get_cluster_metadata()
+        obj = metadata.to_object()
+        obj.pop('topics')  # We have 'describe_topics' for this
+        return obj
 
     @staticmethod
     def _convert_describe_acls_response_to_acls(describe_response):