Return TIMESTAMP columns as native Python datetime objects to improve support for Apache Superset

src/crate/client/cursor.py

@@ -22,6 +22,7 @@
 from .exceptions import ProgrammingError
 from distutils.version import StrictVersion
 import warnings
+from datetime import datetime
 
 BULK_INSERT_MIN_VERSION = StrictVersion("0.42.0")
 
@@ -53,8 +54,35 @@ def execute(self, sql, parameters=None, bulk_parameters=None):
         self._result = self.connection.client.sql(sql, parameters,
                                                   bulk_parameters)
         if "rows" in self._result:
+            if "col_types" in self._result:
+                col_types = self._result["col_types"]
+                tmp_data = self._result["rows"]
+
+                rows_to_convert = self._get_rows_to_convert_to_date(col_types)
+                tmp_data = self._convert_dates_to_datetime(tmp_data, rows_to_convert)
+
+                self._result["rows"] = tmp_data
+
             self.rows = iter(self._result["rows"])
 
+    @staticmethod
+    def _get_rows_to_convert_to_date(col_types):
+        return [True if col_type == 11 or col_type == 15 else False for col_type in col_types]
+
+    @staticmethod
+    def _date_to_datetime(row, rows_to_convert):
+        return list(
+            map(lambda x, y:
+                datetime.fromtimestamp(float(str(x)[0:10])) if y else x,
+                row,
+                rows_to_convert))
+
+    def _convert_dates_to_datetime(self, rows, rows_to_convert):
+        return list(
+            map(lambda x:
+                self._date_to_datetime(x, rows_to_convert),
+                rows))
+
     def executemany(self, sql, seq_of_parameters):
         """
         Prepare a database operation (query or command) and then execute it

src/crate/client/http.py

@@ -315,7 +315,7 @@ class Client(object):
     Crate connection client using crate's HTTP API.
     """
 
-    SQL_PATH = '/_sql'
+    SQL_PATH = '/_sql?types'
     """Crate URI path for issuing SQL statements."""
 
     retry_interval = 30

src/crate/client/sqlalchemy/dialect.py

@@ -43,6 +43,7 @@
     "smallint": sqltypes.SmallInteger,
     "timestamp": sqltypes.TIMESTAMP,
     "timestamp with time zone": sqltypes.TIMESTAMP,
+    "timestamp without time zone": sqltypes.TIMESTAMP,
     "object": Object,
     "integer": sqltypes.Integer,
     "long": sqltypes.NUMERIC,
@@ -64,6 +65,7 @@
     TYPES_MAP["smallint_array"] = ARRAY(sqltypes.SmallInteger)
     TYPES_MAP["timestamp_array"] = ARRAY(sqltypes.TIMESTAMP)
     TYPES_MAP["timestamp with time zone_array"] = ARRAY(sqltypes.TIMESTAMP)
+    TYPES_MAP["timestamp without time zone_array"] = ARRAY(sqltypes.TIMESTAMP)
     TYPES_MAP["long_array"] = ARRAY(sqltypes.NUMERIC)
     TYPES_MAP["bigint_array"] = ARRAY(sqltypes.NUMERIC)
     TYPES_MAP["double_array"] = ARRAY(sqltypes.DECIMAL)
@@ -75,7 +77,6 @@
 except Exception:
     pass
 
-
 log = logging.getLogger(__name__)
 
 
@@ -261,7 +262,7 @@ def get_pk_constraint(self, engine, table_name, schema=None, **kw):
 
             def result_fun(result):
                 rows = result.fetchall()
-                return set(map(lambda el: el[0], rows))
+                return list(set(map(lambda el: el[0], rows)))
         else:
             query = """SELECT constraint_name
                    FROM information_schema.table_constraints