Tornado + Alchemy REST Client
This simple module creates CRUD endpoints for SQLAlchemy table. Its purpose to allow quickly create RESTful APIs, for example for admin panel. List endpoints support pagination and filtering. Was written for Angular’s ng-admin, so this module supports ng-admin querying out of the box
Installation
pip install tornado-alchemy-rest
Usage example
import tornado.web
from tornado.web import URLSpec
from .models import ItemTable
from tornado_alchemy_rest import SingleRESTAPIHandler, ListRESTAPIHandler
class SingleItemHandler(SingleRESTAPIHandler):
table = ItemTable
def delete(self, *args, **kwargs):
raise HTTPError(405)
class ItemHandler(ListRESTAPIHandler):
table = ItemTable
app = tornado.web.Application([
URLSpec(prefix(r'items'), ItemHandler, dict(psql=psql_pool), 'items'),
URLSpec(prefix(r'items/(\d+)'), SingleItemHandler, dict(psql=psql_pool), 'single_item'),
])More complex example, where you can override object creation methods:
class SingleItemHandler(SingleRESTAPIHandler):
table = TableItem
@gen.coroutine
def get_object_dict(self, *args):
obj = yield super().get_object_dict(*args)
cursor = yield self._execute_query(User.select().where(User.c.id == obj['user_id']))
obj['user'] = cursor.fetchone()
return obj
@gen.coroutine
def put_object_dict(self, id, params):
assert params['value'] > 5
yield super().put_object_dict(id, params)
class ItemHandler(ListRESTAPIHandler):
table = TableItem
@gen.coroutine
def get_object_list(self, query):
objects = yield super().get_object_list(query)
for obj in objects:
cursor = yield self._execute_query(User.select().where(User.c.id == obj['user_id']))
obj['user'] = cursor.fetchone()
raise gen.Return(objects)
@gen.coroutine
def post_object_dict(self, params):
assert params['value'] > 5
yield super().post_object_dict(params)Querying
To get second page with ordering by id DESC you need to do that query:
GET /item?_page=2&_perPage=30&_sortField=id&_sortDir=DESC
To get all items, where name contains “test” and type is 5 and
value is 7 or 6, you will need that query:
GET /item?_filters={"name__contains":"test", "type":5, "value__any":[7,6]}
Query params
- _page – page name
- _perPage – rows per page
- _sortField – field to order by
- _sortDir – direction to sort by
- _filters – filter items with given params. Currently supported filters are: “” (equality), startswith, contains, icontains, any, ne
Join support
That will return data from both tables at some time:
class SingleItemHandler(SingleRESTAPIHandler):
table = TableItem
def get_from(self):
return self.table.join(TableUser, isouter=True)Requirements
tornado, sqlalchemy
