Python（Flask RESTful API）修改对象

Question

I am having an issue with an object (configuration object) that I want both the python program and external API users to modify. If I use the API and PUT new data, the data is saved. If I have the Python program try modifying the object, I cannot observe that change when doing a GET.As you can see, I change config.encoding to "test", but when doing a GET, I do not observe the change. I still see encoding set to "ASCII". I am relatively new to Python and may be overlooking something simple.

Thanks.

config = util.Config()

class api_Config(Resource):
    def get(self, id):
        return [{"id": config.id,
                 "capture": config.capture,
                 "controller": config.controller,
                 "gateway_ip_address": config.gateway_ip_address,
                 "port": config.port,
                 "interval_rate": config.interval_rate,
                 "encoding": config.encoding}], 200
    def put(self, id):
        parser = reqparse.RequestParser()
        parser.add_argument("capture")
        parser.add_argument("controller")
        parser.add_argument("gateway_ip_address")
        parser.add_argument("port")
        parser.add_argument("interval_rate")
        parser.add_argument("encoding")
        args = parser.parse_args()
        config.capture = args["capture"]
        config.controller = args["controller"]
        config.gateway_ip_address = args["gateway_ip_address"]
        config.port = args["port"]
        config.interval_rate = args["interval_rate"]
        config.encoding = args["encoding"]
        return [{"id": config.id,
                 "capture": config.capture,
                 "controller": config.controller,
                 "gateway_ip_address": config.gateway_ip_address,
                 "port": config.port,
                 "interval_rate": config.interval_rate,
                 "encoding": config.encoding}], 200

if __name__== "__main__":
        app = Flask(__name__)
        api = Api(app)
        config = util.Config()
        api.add_resource(api_Config, '/<string:id>')
        app.run(debug=True)
        print config.encoding
        config.encoding = "test"

Answer 1

There are two places at which you are creating your config object. One is at the very first line, where you say config = util.Config() which looks like either util.Config is a class and then util.Config() returns an instance of that class or it is a function and whatever that function returns will be assigned to config . Either way, that will be the config object used by your api_Config.get method.

The second place where you create an instance of this config object is after your if __name__== "__main__": block, which will be an entirely new object and will not be used by those api handlers.

It might be enough for you to remove that second definition and use

if __name__== "__main__":
    app = Flask(__name__)
    api = Api(app)

    api.add_resource(api_Config, '/<string:id>')
    app.run(debug=True)
    print config.encoding
    config.encoding = "test"

without modifying the rest.