table: show nested metrics as separate columns (#130)

* table: show nested metrics as separate columns

* add docstring

* use flatten_dict

* ignore mypy error

setup.cfg

@@ -27,6 +27,7 @@ packages = find:
 [options.extras_require]
 table =
     tabulate>=0.8.7
+    flatten_dict<1,>=0.4.1
 markdown =
     %(table)s
     matplotlib

src/dvc_render/utils.py

@@ -1,5 +1,9 @@
+from flatten_dict import flatten  # type: ignore
+
+
 def list_dict_to_dict_list(list_dict):
     """Convert from list of dictionaries to dictionary of lists."""
     if not list_dict:
         return {}
-    return {k: [x[k] for x in list_dict] for k in list_dict[0]}
+    flat_list_dict = [flatten(d, reducer="dot") for d in list_dict]
+    return {k: [x[k] for x in flat_list_dict] for k in flat_list_dict[0]}

tests/test_table.py

@@ -24,3 +24,11 @@ def test_generate_markdown():
     assert "|   foo |   bar |" in md
     assert "|-------|-------|" in md
     assert "|     1 |     2 |" in md
+
+
+def test_nested():
+    datapoints = [{"foo": {"bar": 1}}]
+    html = TableRenderer(datapoints, "metrics.json").generate_html()
+    assert "<p>metrics_json</p>" in html
+    assert '<tr><th style="text-align: right;">  foo.bar</th></tr>' in html
+    assert '<tr><td style="text-align: right;">        1</td></tr>' in html