I'm planning to design some REST APIs with Twisted in Python. For example, I want to use the HTTP method "GET" to fetch a single user's information:

GET http://myhost:8000/api/v1.0/users/%5Buser_id]

I know I should inherit the twisted.web.resource.Resource and implement "getChild" by myself. The question is, should I implement a class for each segment of the URI? If so, I have to implement class API, class V1, class Users and Class User. In other words, if there're 10 segments in the URI, do I have to implement 10 classes to represent those resources?

At 2015-10-25 20:13:58, "Burak Arslan" burak.arslan@arskom.com.tr wrote: Hey!

On 10/25/15 13:04, Wang Yan wrote:

Hi,

I'm confused about how to design REST APIs with Twisted, especially when my app have to interact with MySQL.

Is there any basic design patterns for this kind of situation?

I do Spyne, and I think it's fa-bu-lous for building any web API on top of twisted.

It's a bit different from what you to with stock Twisted though. More specifically, there's no NOT_DONE_YET. The client hangs as long as you keep returning `Deferred`s. Once you return a non-deferred (and hopefully something that's compatible with your designated return type) that object is serialized using the `out_protocol` you pass to your `Application` and the resulting byte stream is written to the outgoing stream of your transport of choice. In case of a HTTP-based api, it's passed to the `transport.write()` function of a `twisted.web.Resource` instance, along with the outgoing headers that you set.

As for the MySQL part, I use SQLAlchemy exclusively from inside a function called by deferToThread. Spyne integrates with SQLAlchemy as well, so you can return directly what SQLA returns, be it objects or rows.

Here's a simple example: https://github.com/arskom/spyne/blob/master/examples/twisted/resource.py

There's a boilerplate generator here: http://spyne.io/

I hope you find it useful. Any questions, people@spyne.io is also at your service.

Best, Burak

Thank you to remind me of Klein. I'm very new to Twisted and Klein. What I've known is that Klein is a little like Flask, with which I can implement a UserAPI as follows:

from flask import Flask from flask.ext.restful import Api, Resource

api = Flask(__name__) api = Api(app)

class UserAPI(Resource): def get(self, user_id): pass

def post(self, user_id): pass

api.add_resource(UserAPI, '/users/int:id', endpoint='user')

Is there any similar usage in Klein?

在 2015-11-04 12:09:29，"Mashiat Sarker Shakkhar" mashiat.sarker@gmail.com 写道：

On 11/3/15 10:15 PM, Wang Yan wrote:

I'm planning to design some REST APIs with Twisted in Python. For example, I want to use the HTTP method "GET" to fetch a single user's information:

GET http://myhost:8000/api/v1.0/users/%5Buser_id]

I know I should inherit the twisted.web.resource.Resource and implement "getChild" by myself. The question is, should I implement a class for each segment of the URI? If so, I have to implement class API, class V1, class Users and Class User. In other words, if there're 10 segments in the URI, do I have to implement 10 classes to represent those resources?

Twisted is too low-level for such use in my opinion. We use Klein (https://github.com/twisted/klein) which offers nice abstraction above Twisted. I know this does not answer your question. Just wanted to make sure that you are aware of possible options.

-Shakkhar

[...]

Absolutely that's what I'm looking for! Thanks a lot!

However, I'm wondering if Twisted and Klein support filtering results. For example, the User table in MySQL contains id, name and age fields. How can I get all users whose name are "Alan" and age > 16? It seems I need a filter, but I'm not sure how to implement such a filter or resource with Twisted and Klein.

在 2015-11-06 06:02:53，"Glyph Lefkowitz" glyph@twistedmatrix.com 写道：

On Nov 5, 2015, at 1:28 AM, Wang Yan snailcoder@163.com wrote:

Thank you to remind me of Klein. I'm very new to Twisted and Klein. What I've known is that Klein is a little like Flask, with which I can implement a UserAPI as follows:

from flask import Flask from flask.ext.restful import Api, Resource

api = Flask(__name__) api = Api(app)

class UserAPI(Resource): def get(self, user_id): pass

def post(self, user_id): pass

api.add_resource(UserAPI, '/users/int:id', endpoint='user')

Is there any similar usage in Klein?

Yes; in fact this extension for Flask is similar to how twisted.web works internally. I think you're looking for something like this:

from klein import run, route

from twisted.web.resource import Resource

class User(Resource, object): def __init__(self, user_id): super(User, self).__init__() self.user_id = user_id def render_GET(self, request): pass def render_POST(self, request): pass

@route("/users/int:user_id") def user(request, user_id): return User(user_id)

run("localhost", 8080)