feat: Add an upsert_item method

flask_resty/view.py

@@ -3,6 +3,7 @@
 import flask
 from flask.views import MethodView
 from marshmallow import ValidationError, fields
+from sqlalchemy import inspect
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.orm import Load
 from sqlalchemy.orm.exc import NoResultFound
@@ -616,7 +617,7 @@ def paginate_list_query(self, query):
         return self.pagination.get_page(query, self)
 
     def get_item_or_404(self, id, **kwargs):
-        """Get an item by ID; raise a 404 if it not found.
+        """Get an item by ID; raise a 404 if not found.
 
         This will get an item by ID per `get_item` below. If no item is found,
         it will rethrow the `NoResultFound` exception as an HTTP 404.
@@ -632,6 +633,23 @@ def get_item_or_404(self, id, **kwargs):
 
         return item
 
+    def get_item_or_none(self, id, **kwargs):
+        """Get an item by ID; return `None` if not found.
+
+        This will get an item by ID per `get_item` below. If no item is found,
+        it will return `None`.
+
+        :param id: The item ID.
+        :return: The item corresponding to the ID, if there is one.
+        :rtype: object
+        """
+        try:
+            item = self.get_item(id, **kwargs)
+        except NoResultFound:
+            return None
+
+        return item
+
     def get_item(
         self, id, *, with_for_update=False, create_transient_stub=False,
     ):
@@ -841,6 +859,14 @@ def update_item_raw(self, item, data):
         for key, value in data.items():
             setattr(item, key, value)
 
+    def upsert_item(self, item, data):
+        if item is not None:
+            item = self.update_item(item, data) or item
+        else:
+            item = self.create_and_add_item(data)
+
+        return item
+
     def delete_item(self, item):
         """Delete an existing item.
 
@@ -1082,19 +1108,17 @@ def upsert(self, id, *, with_for_update=False):
         :rtype: :py:class:`flask.Response`
         """
         data_in = self.get_request_data(expected_id=id)
+        item = self.get_item_or_none(id, with_for_update=with_for_update)
 
-        try:
-            item = self.get_item(id, with_for_update=with_for_update)
-        except NoResultFound:
-            item = self.create_and_add_item(data_in)
-            self.commit()
-
-            return self.make_created_response(item)
-        else:
-            item = self.update_item(item, data_in) or item
-            self.commit()
+        item = self.upsert_item(item, data_in) or item
+        updated = inspect(item).persistent
+        self.commit()
 
-            return self.make_item_response(item)
+        return (
+            self.make_item_response(item)
+            if updated
+            else self.make_created_response(item)
+        )
 
     def destroy(self, id):
         """Delete the item for the specified ID.