API for topics (#1023)

* initial commit

* private functions

Author: sahithyaravi

openml/datasets/functions.py

@@ -873,6 +873,47 @@ def fork_dataset(data_id: int) -> int:
     return int(data_id)
 
 
+def _topic_add_dataset(data_id: int, topic: str):
+    """
+    Adds a topic for a dataset.
+    This API is not available for all OpenML users and is accessible only by admins.
+    Parameters
+    ----------
+    data_id : int
+        id of the dataset for which the topic needs to be added
+    topic : str
+        Topic to be added for the dataset
+   """
+    if not isinstance(data_id, int):
+        raise TypeError("`data_id` must be of type `int`, not {}.".format(type(data_id)))
+    form_data = {"data_id": data_id, "topic": topic}
+    result_xml = openml._api_calls._perform_api_call("data/topicadd", "post", data=form_data)
+    result = xmltodict.parse(result_xml)
+    data_id = result["oml:data_topic"]["oml:id"]
+    return int(data_id)
+
+
+def _topic_delete_dataset(data_id: int, topic: str):
+    """
+    Removes a topic from a dataset.
+    This API is not available for all OpenML users and is accessible only by admins.
+    Parameters
+    ----------
+    data_id : int
+        id of the dataset to be forked
+    topic : str
+        Topic to be deleted
+
+   """
+    if not isinstance(data_id, int):
+        raise TypeError("`data_id` must be of type `int`, not {}.".format(type(data_id)))
+    form_data = {"data_id": data_id, "topic": topic}
+    result_xml = openml._api_calls._perform_api_call("data/topicdelete", "post", data=form_data)
+    result = xmltodict.parse(result_xml)
+    data_id = result["oml:data_topic"]["oml:id"]
+    return int(data_id)
+
+
 def _get_dataset_description(did_cache_dir, dataset_id):
     """Get the dataset description as xml dictionary.
 

tests/test_datasets/test_dataset_functions.py

@@ -37,6 +37,8 @@
     _get_online_dataset_format,
     DATASETS_CACHE_DIR_NAME,
     _get_dataset_parquet,
+    _topic_add_dataset,
+    _topic_delete_dataset,
 )
 from openml.datasets import fork_dataset, edit_dataset
 from openml.tasks import TaskType, create_task
@@ -911,6 +913,24 @@ def test_get_online_dataset_arff(self):
             "ARFF files are not equal",
         )
 
+    def test_topic_api_error(self):
+        # Check server exception when non-admin accessses apis
+        self.assertRaisesRegex(
+            OpenMLServerException,
+            "Topic can only be added/removed by admin.",
+            _topic_add_dataset,
+            data_id=31,
+            topic="business",
+        )
+        # Check server exception when non-admin accessses apis
+        self.assertRaisesRegex(
+            OpenMLServerException,
+            "Topic can only be added/removed by admin.",
+            _topic_delete_dataset,
+            data_id=31,
+            topic="business",
+        )
+
     def test_get_online_dataset_format(self):
 
         # Phoneme dataset