Make new_table accept a dictionary as input (#4966)

py/server/deephaven/table_factory.py

@@ -5,7 +5,7 @@
 """ This module provides various ways to make a Deephaven table. """
 
 import datetime
-from typing import Callable, List, Dict, Any, Union, Sequence, Tuple
+from typing import Callable, List, Dict, Any, Union, Sequence, Tuple, Mapping
 
 import jpy
 import numpy as np
@@ -93,11 +93,17 @@ def time_table(period: Union[Duration, int, str, datetime.timedelta, np.timedelt
         raise DHError(e, "failed to create a time table.") from e
 
 
-def new_table(cols: List[InputColumn]) -> Table:
-    """Creates an in-memory table from a list of input columns. Each column must have an equal number of elements.
+def new_table(cols: Union[List[InputColumn], Mapping[str, Sequence]]) -> Table:
+    """Creates an in-memory table from a list of input columns or a Dict (mapping) of column names and column data.
+    Each column must have an equal number of elements.
+
+    When the input is a mapping, an intermediary Pandas DataFrame is created from the mapping, which then is converted
+    to an in-memory table. In this case, as opposed to when the input is a list of InputColumns, the column types are
+    determined by Pandas' type inference logic.
 
     Args:
-        cols (List[InputColumn]): a list of InputColumn
+        cols (Union[List[InputColumn], Mapping[str, Sequence]]): a list of InputColumns or a mapping of columns
+            names and column data.
 
     Returns:
         a Table
@@ -106,7 +112,12 @@ def new_table(cols: List[InputColumn]) -> Table:
         DHError
     """
     try:
-        return Table(j_table=_JTableFactory.newTable(*[col.j_column for col in cols]))
+        if isinstance(cols, list):
+            return Table(j_table=_JTableFactory.newTable(*[col.j_column for col in cols]))
+        else:
+            from deephaven.pandas import to_table
+            df = pd.DataFrame(cols).convert_dtypes()
+            return to_table(df)
     except Exception as e:
         raise DHError(e, "failed to create a new time table.") from e
 

py/server/tests/test_table_factory.py

@@ -136,8 +136,68 @@ def test_new_table(self):
             jobj_col(name="JObj", data=[jobj1, jobj2]),
         ]
 
-        t = new_table(cols=cols)
-        self.assertEqual(t.size, 2)
+    def test_new_table_dict(self):
+        jobj1 = JArrayList()
+        jobj1.add(1)
+        jobj1.add(-1)
+        jobj2 = JArrayList()
+        jobj2.add(2)
+        jobj2.add(-2)
+        bool_cols = {
+            "Boolean": [True, False],
+        }
+        integer_cols = {
+            "Byte": (1, -1),
+            "Short": [1, -1],
+            "Int": [1, -1],
+            "Long": [1, -1],
+        }
+        float_cols = {
+            "Float": [1.01, -1.01],
+            "Double": [1.01, -1.01],
+        }
+        string_cols = {
+            "String": np.array(["foo", "bar"]),
+        }
+        datetime_cols = {
+            "Datetime": np.array([1, -1], dtype=np.dtype("datetime64[ns]"))
+        }
+
+        obj_cols = {
+            "PyObj": [CustomClass(1, "1"), CustomClass(-1, "-1")],
+            "PyObj1": [[1, 2, 3], CustomClass(-1, "-1")],
+            "PyObj2": [False, 'False'],
+            "JObj": [jobj1, jobj2],
+        }
+
+        dtype_cols_map = {
+            dtypes.bool_: bool_cols,
+            dtypes.int64: integer_cols,
+            dtypes.float64: float_cols,
+            dtypes.string: string_cols,
+            dtypes.Instant: datetime_cols,
+            dtypes.PyObject: obj_cols
+        }
+
+        for dtype, cols in dtype_cols_map.items():
+            with self.subTest(f"Testing {dtype}"):
+                t = new_table(cols=cols)
+                self.assertEqual(t.size, 2)
+                for c in t.columns:
+                    self.assertEqual(c.data_type, dtype)
+
+        dtype_np_cols_map = {
+            dtypes.int8: np.array([1, -1], dtype=np.int8),
+            dtypes.int16: np.array([1, -1], dtype=np.int16),
+            dtypes.int32: np.array([1, -1], dtype=np.int32),
+            dtypes.int64: np.array([1, -1], dtype=np.int64),
+            dtypes.float32: np.array([1.01, -1.01], dtype=np.float32),
+            dtypes.float64: np.array([1.01, -1.01], dtype=np.float64),
+        }
+        d_cols = {dtype.j_name.capitalize(): cols for dtype, cols in dtype_np_cols_map.items()}
+        t = new_table(cols=d_cols)
+        for tc, dtype in zip(t.columns, dtype_np_cols_map.keys()):
+            self.assertEqual(tc.data_type, dtype)
 
     def test_new_table_nulls(self):
         null_cols = [
@@ -155,6 +215,7 @@ def test_new_table_nulls(self):
         t = new_table(cols=null_cols)
         self.assertEqual(t.to_string().count("null"), len(null_cols))
 
+
     def test_input_column_error(self):
         j_al = JArrayList()