Feat: Adding table comment and columns comment for SQLLab (#10844)

* Adding table comment and columns comment for backend

* fix mypy

* Fix CI

* adding wider catch

* use logger

* fix lint

superset/databases/utils.py

@@ -73,6 +73,7 @@ def get_table_metadata(
     indexes = get_indexes_metadata(database, table_name, schema_name)
     keys += foreign_keys + indexes
     payload_columns: List[Dict[str, Any]] = []
+    table_comment = database.get_table_comment(table_name, schema_name)
     for col in columns:
         dtype = get_col_type(col)
         payload_columns.append(
@@ -81,6 +82,7 @@ def get_table_metadata(
                 "type": dtype.split("(")[0] if "(" in dtype else dtype,
                 "longType": dtype,
                 "keys": [k for k in keys if col["name"] in k["column_names"]],
+                "comment": col.get("comment"),
             }
         )
     return {
@@ -97,4 +99,5 @@ def get_table_metadata(
         "primaryKey": primary_key,
         "foreignKeys": foreign_keys,
         "indexes": keys,
+        "comment": table_comment,
     }

superset/db_engine_specs/base.py

@@ -655,6 +655,30 @@ def get_view_names(
             views = [re.sub(f"^{schema}\\.", "", view) for view in views]
         return sorted(views)
 
+    @classmethod
+    def get_table_comment(
+        cls, inspector: Inspector, table_name: str, schema: Optional[str]
+    ) -> Optional[str]:
+        """
+        Get comment of table from a given schema and table
+
+        :param inspector: SqlAlchemy Inspector instance
+        :param table_name: Table name
+        :param schema: Schema name. If omitted, uses default schema for database
+        :return: comment of table
+        """
+        comment = None
+        try:
+            comment = inspector.get_table_comment(table_name, schema)
+            comment = comment.get("text") if isinstance(comment, dict) else None
+        except NotImplementedError:
+            # It's expected that some dialects don't implement the comment method
+            pass
+        except Exception as ex:  # pylint: disable=broad-except
+            logger.error("Unexpected error while fetching table comment")
+            logger.exception(ex)
+        return comment
+
     @classmethod
     def get_columns(
         cls, inspector: Inspector, table_name: str, schema: Optional[str]

superset/models/core.py

@@ -611,6 +611,11 @@ def get_table(self, table_name: str, schema: Optional[str] = None) -> Table:
             autoload_with=self.get_sqla_engine(),
         )
 
+    def get_table_comment(
+        self, table_name: str, schema: Optional[str] = None
+    ) -> Optional[str]:
+        return self.db_engine_spec.get_table_comment(self.inspector, table_name, schema)
+
     def get_columns(
         self, table_name: str, schema: Optional[str] = None
     ) -> List[Dict[str, Any]]:

tests/databases/api_tests.py

@@ -500,6 +500,7 @@ def test_get_table_metadata(self):
         self.assertEqual(rv.status_code, 200)
         response = json.loads(rv.data.decode("utf-8"))
         self.assertEqual(response["name"], "birth_names")
+        self.assertIsNone(response["comment"])
         self.assertTrue(len(response["columns"]) > 5)
         self.assertTrue(response.get("selectStar").startswith("SELECT"))