Ensure that the source/readme files can only be downloaded in txt format

sdv/datasets/demo.py

@@ -384,6 +384,14 @@ def _get_text_file_content(modality, dataset_name, filename, output_filepath=Non
             The decoded text contents if the file exists, otherwise ``None``.
     """
     _validate_modalities(modality)
+    if output_filepath is not None and not str(output_filepath).endswith('.txt'):
+        fname = (filename or '').lower()
+        file_type = 'README' if 'readme' in fname else 'source'
+        raise ValueError(
+            f'The {file_type} can only be saved as a txt file. '
+            "Please provide a filepath ending in '.txt'"
+        )
+
     dataset_prefix = f'{modality}/{dataset_name}/'
     contents = _list_objects(dataset_prefix)
 

sdv/single_table/copulas.py

@@ -5,7 +5,6 @@
 import warnings
 from copy import deepcopy
 
-import copulas
 import copulas.univariate
 import numpy as np
 import pandas as pd

tests/unit/datasets/test_demo.py

@@ -762,13 +762,13 @@ def fake(modality, dataset_name, filename, output_filepath=None):
     monkeypatch.setattr('sdv.datasets.demo._get_text_file_content', fake)
 
     # Run
-    r = get_readme('single_table', 'dataset1', '/tmp/readme')
-    s = get_source('single_table', 'dataset1', '/tmp/source')
+    readme = get_readme('single_table', 'dataset1', '/tmp/readme.txt')
+    source = get_source('single_table', 'dataset1', '/tmp/source.txt')
 
     # Assert
-    assert r == 'X' and s == 'X'
-    assert calls[0] == ('single_table', 'dataset1', 'README.txt', '/tmp/readme')
-    assert calls[1] == ('single_table', 'dataset1', 'SOURCE.txt', '/tmp/source')
+    assert readme == 'X' and source == 'X'
+    assert calls[0] == ('single_table', 'dataset1', 'README.txt', '/tmp/readme.txt')
+    assert calls[1] == ('single_table', 'dataset1', 'SOURCE.txt', '/tmp/source.txt')
 
 
 @patch('sdv.datasets.demo._get_data_from_bucket')
@@ -807,3 +807,17 @@ def test_get_source_raises_if_output_file_exists(mock_list, mock_get, tmp_path):
     err = f"A file named '{out}' already exists. Please specify a different filepath."
     with pytest.raises(ValueError, match=re.escape(err)):
         get_source('single_table', 'dataset1', str(out))
+
+
+def test_get_readme_raises_for_non_txt_output():
+    """get_readme should raise ValueError if output path is not .txt."""
+    err = "The README can only be saved as a txt file. Please provide a filepath ending in '.txt'"
+    with pytest.raises(ValueError, match=re.escape(err)):
+        get_readme('single_table', 'dataset1', '/tmp/readme.md')
+
+
+def test_get_source_raises_for_non_txt_output():
+    """get_source should raise ValueError if output path is not .txt."""
+    err = "The source can only be saved as a txt file. Please provide a filepath ending in '.txt'"
+    with pytest.raises(ValueError, match=re.escape(err)):
+        get_source('single_table', 'dataset1', '/tmp/source.pdf')