TCrudge - simple async CRUDL based on Tornado and Peewee ORM (Peewee Async)

Full documentation (https://pythonhosted.org/tcrudge/)

What is it?

Simple configurable framework to create CRUDL (Create, Read, Update, Delete, List) for models

Why?

Tornado is fast. Peewee is great. REST is wonderful.

Dependencies

• Tornado (https://github.com/tornadoweb/tornado)
• Peewee (https://github.com/coleifer/peewee)
• Peewee-async (https://github.com/05bit/peewee-async)
• Modified JSON schema generator by [Shalamov Maxim] (https://github.com/mvshalamov) (https://github.com/mvshalamov/GenSON)

Installation

tcrudge is not distributed by pip (https://pypi.python.org/pypi). So use installation via GitHub:

pip install git+https://github.com/CodeTeam/tcrudge.git

How to?

Describe models using Peewee ORM. Subclass tcrudge.ApiListHandler and tcrudge.ApiItemHandler. Connect handlers with models using model_cls handler attribute. Add urls to tornado.Application url dispatcher.

For detailed example see tests (also, tests are available in Docker container with py.test).

You can run tests in docker container only. You'll need docker and docker-compose.

1. Go to project root directory
2. Run docker-compose up, it builts and runs containers.
3. Go to tcrudge container bash: docker exec -ti tcrudge_tcrudge_1 bash
4. Run: DATABASE_URL=postgresql://user:dbpass@pg/test pytest

Features?

1. DELETE request on item is disabled by default. To enable it implement _delete method in your model.
2. Models are fat. _create, _update, _delete methods are supposed to provide different logic on CRUD operations
3. Django-style filtering in list request: __gt, __gte, __lt, __lte, __in, __isnull, __like, __ilike, __ne are supported. Use /?model_field__<filter_type>=<filter_condition> for complex or /?model_field=<filter_condition> for simple filtering.
4. Django-style order by: use /?order_by=<field_1>,<field_2> etc
5. Serialization is provided by Peewee: playhouse.shortcuts.model_to_dict. recurse, exclude and max_depth params are implemented in base class for better experience. If you want to serialize recurse foreign keys, do not forget to modify get_queryset method (see Peewee docs for details, use .join() and .select())
6. Validation is provided out-of-the box via jsonschema. Just set input schemas for base methods (e.g. post_schema_input, get_schema_input etc). Request query is validated for GET and HEAD. Request body is validated for POST, PUT and DELETE.
7. Pagination is activated by default for lists. Use default_limit and mac_limit for customization. Pagination params are set through headers (X-Limit, X-Offset) or query: /?limit=100&offset=5. Total amount of items is not returned by default. HEAD request should be sent or total param set to 1: /?total=1
8. List handler supports default filtering and ordering. Use default_filter and default_order_by class properties.

Example

Application

app_handlers = [
    ('^/api/v1/companies/', CompanyListHandler),
    ('^/api/v1/companies/([^/]+)/', CompanyDetailHandler)
]

application = web.Application(app_handlers, debug=settings.DEBUG, template_path=settings.TEMPLATE_PATH)


#ORM
application.objects = peewee_async.Manager(db)


def runserver():
    if settings.DEBUG:
        application.listen(settings.PORT, '0.0.0.0')
    else:
        server = HTTPServer(application)
        server.bind(settings.PORT)
        server.start(0)
    loop = asyncio.get_event_loop()
    loop.run_forever()

Model

DB table must exist; Fields in table must correspond to model fields

class Company(CustomBaseModel):
    company_inn = peewee.TextField()
    active = peewee.BooleanField()
    created_at = peewee.DateTimeField()
    updated_at = peewee.DateTimeField()

    class Meta:
        db_table = "company"

Handlers

class CompanyDetailHandler(ApiItemHandler):
    model_cls = Company

    get_schema_input = GET_SCHEMA
    put_schema_input = UPDATE_SCHEMA
    delete_schema_input = DELETE_SCHEMA


class CompanyListHandler(ApiListHandler):
    model_cls = Company

    post_schema_input = INSERT_SCHEMA
    get_schema_input = GET_SCHEMA

    default_filter = {'active': True}

Сontributors

• [Borisov Sergey] (https://github.com/juntatalor)
• [Shalamov Maxim] (https://github.com/mvshalamov)
• [Nikolaev Alexander] (https://github.com/wokli)
• [Krasavina Alina] (https://github.com/thaelathy)