Fix calls with empty lists (#1662)

* Empty topic collection allowed

* Empty topic names disallowed

* Test with different options

* New _make_futmap_result_from_list method

Author: emasab

src/confluent_kafka/admin/__init__.py

@@ -199,31 +199,6 @@ def _make_consumer_groups_result(f, futmap):
             for _, fut in futmap.items():
                 fut.set_exception(e)
 
-    @staticmethod
-    def _make_describe_topics_result(f, futmap):
-        """
-        Map per-topic results to per-topic futures in futmap.
-        """
-        try:
-
-            results = f.result()
-            futmap_values = list(futmap.values())
-            len_results = len(results)
-            len_futures = len(futmap_values)
-            if len_results != len_futures:
-                raise RuntimeError(
-                    "Results length {} is different from future-map length {}".format(len_results, len_futures))
-            for i, result in enumerate(results):
-                fut = futmap_values[i]
-                if isinstance(result, KafkaError):
-                    fut.set_exception(KafkaException(result))
-                else:
-                    fut.set_result(result)
-        except Exception as e:
-            # Request-level exception, raise the same for all topics
-            for _, fut in futmap.items():
-                fut.set_exception(e)
-
     @staticmethod
     def _make_consumer_group_offsets_result(f, futmap):
         """
@@ -298,6 +273,28 @@ def _make_user_scram_credentials_result(f, futmap):
             for _, fut in futmap.items():
                 fut.set_exception(e)
 
+    @staticmethod
+    def _make_futmap_result_from_list(f, futmap):
+        try:
+
+            results = f.result()
+            futmap_values = list(futmap.values())
+            len_results = len(results)
+            len_futures = len(futmap_values)
+            if len_results != len_futures:
+                raise RuntimeError(
+                    "Results length {} is different from future-map length {}".format(len_results, len_futures))
+            for i, result in enumerate(results):
+                fut = futmap_values[i]
+                if isinstance(result, KafkaError):
+                    fut.set_exception(KafkaException(result))
+                else:
+                    fut.set_result(result)
+        except Exception as e:
+            # Request-level exception, raise the same for all topics
+            for _, fut in futmap.items():
+                fut.set_exception(e)
+
     @staticmethod
     def _make_futmap_result(f, futmap):
         try:
@@ -948,11 +945,8 @@ def describe_topics(self, topics, **kwargs):
         if not isinstance(topic_names, list):
             raise TypeError("Expected list of topic names to be described")
 
-        if len(topic_names) == 0:
-            raise ValueError("Expected at least one topic to be described")
-
-        f, futmap = AdminClient._make_futures(topic_names, None,
-                                              AdminClient._make_describe_topics_result)
+        f, futmap = AdminClient._make_futures_v2(topic_names, None,
+                                                 AdminClient._make_futmap_result_from_list)
 
         super(AdminClient, self).describe_topics(topic_names, f, **kwargs)
 

src/confluent_kafka/src/Admin.c

@@ -2326,36 +2326,43 @@ PyObject *Admin_describe_topics (Handle *self, PyObject *args, PyObject *kwargs)
                             &options.include_authorized_operations))
                 goto err;
 
-        if (!PyList_Check(topics) || (topics_cnt = (int)PyList_Size(topics)) < 1) {
-                PyErr_SetString(PyExc_ValueError,
-                                "Expected non-empty list of topics");
+        if (!PyList_Check(topics)) {
+                PyErr_SetString(PyExc_TypeError,
+                                "Expected a list of topics");
                 goto err;
         }
 
-        c_topics = malloc(sizeof(char *) * topics_cnt);
+        topics_cnt = PyList_Size(topics);
 
-        for (i = 0 ; i < topics_cnt ; i++) {
-                PyObject *topic = PyList_GET_ITEM(topics, i);
-                PyObject *utopic;
-                PyObject *uotopic = NULL;
+        if (topics_cnt) {
+                c_topics = malloc(sizeof(char *) * topics_cnt);
+                for (i = 0 ; i < topics_cnt ; i++) {
+                        PyObject *topic = PyList_GET_ITEM(topics, i);
+                        PyObject *uotopic = NULL;
 
-                if (topic == Py_None ||
-                    !(utopic = cfl_PyObject_Unistr(topic))) {
-                        PyErr_Format(PyExc_ValueError,
-                                     "Expected list of topics strings, "
-                                     "not %s",
-                                     ((PyTypeObject *)PyObject_Type(topic))->
-                                     tp_name);
-                        goto err;
-                }
+                        if (topic == Py_None ||
+                            !PyUnicode_Check(topic)) {
+                                PyErr_Format(PyExc_TypeError,
+                                        "Expected list of topics strings, "
+                                        "not %s",
+                                        ((PyTypeObject *)PyObject_Type(topic))->
+                                        tp_name);
+                                goto err;
+                        }
 
-                c_topics[i] = cfl_PyUnistr_AsUTF8(utopic, &uotopic);
+                        c_topics[i] = cfl_PyUnistr_AsUTF8(topic, &uotopic);
+                        Py_XDECREF(uotopic);
 
-                Py_XDECREF(utopic);
-                Py_XDECREF(uotopic);
+                        if (!c_topics[i][0]) {
+                                PyErr_Format(PyExc_ValueError,
+                                        "Empty topic name at index %d isn't "
+                                        "allowed", i);
+                                goto err;
+                        }
+                }
         }
-        c_topic_collection = rd_kafka_TopicCollection_of_topic_names(c_topics, topics_cnt);
 
+        c_topic_collection = rd_kafka_TopicCollection_of_topic_names(c_topics, topics_cnt);
         c_options = Admin_options_to_c(self, RD_KAFKA_ADMIN_OP_DESCRIBETOPICS,
                                        &options, future);
         if (!c_options)  {

tests/test_Admin.py

@@ -637,18 +637,55 @@ def test_describe_consumer_groups_api():
 def test_describe_topics_api():
     a = AdminClient({"socket.timeout.ms": 10})
 
-    topic_names = ["test-topic-1", "test-topic-2"]
+    # Wrong option types
+    for kwargs in [{"include_authorized_operations": "wrong_type"},
+                   {"request_timeout": "wrong_type"}]:
+        with pytest.raises(TypeError):
+            a.describe_topics(TopicCollection([]), **kwargs)
 
-    a.describe_topics(TopicCollection(topic_names))
+    # Wrong option values
+    for kwargs in [{"request_timeout": -1}]:
+        with pytest.raises(ValueError):
+            a.describe_topics(TopicCollection([]), **kwargs)
 
-    with pytest.raises(TypeError):
-        a.describe_topics(topic_names)
+    # Test with different options
+    for kwargs in [{},
+                   {"include_authorized_operations": True},
+                   {"request_timeout": 0.01},
+                   {"include_authorized_operations": False,
+                    "request_timeout": 0.01}]:
 
-    with pytest.raises(TypeError):
-        a.describe_topics("test-topic-1")
+        topic_names = ["test-topic-1", "test-topic-2"]
 
-    with pytest.raises(ValueError):
-        a.describe_topics(TopicCollection([]))
+        # Empty TopicCollection returns empty futures
+        fs = a.describe_topics(TopicCollection([]), **kwargs)
+        assert len(fs) == 0
+
+        # Normal call
+        fs = a.describe_topics(TopicCollection(topic_names), **kwargs)
+        for f in concurrent.futures.as_completed(iter(fs.values())):
+            e = f.exception(timeout=1)
+            assert isinstance(e, KafkaException)
+            assert e.args[0].code() == KafkaError._TIMED_OUT
+
+        # Wrong argument type
+        for args in [
+                        [topic_names],
+                        ["test-topic-1"],
+                        [TopicCollection([3])],
+                        [TopicCollection(["correct", 3])],
+                        [TopicCollection([None])]
+                    ]:
+            with pytest.raises(TypeError):
+                a.describe_topics(*args, **kwargs)
+
+        # Wrong argument value
+        for args in [
+                        [TopicCollection([""])],
+                        [TopicCollection(["correct", ""])]
+                    ]:
+            with pytest.raises(ValueError):
+                a.describe_topics(*args, **kwargs)
 
 
 def test_describe_cluster():