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'NoneType'オブジェクトは添え字化できません

flask + pythonで記述されたサーバーを使用するiOSアプリを作成していますが、サーバーに接続してユーザーを登録すると、「NoneType」オブジェクトがサブスクリプト可能エラーではありません基本的に私の質問は、このエラーの原因とこれを修正する方法です。また、誰かがこれを行うためのさまざまなまたはより簡単な方法の正しい方向に私を向けることができれば、感謝します！

Server.pyファイルは次のとおりです。

import bcrypt
from flask import Flask, request, make_response,jsonify
from flask_restful import Resource, Api
from pymongo import MongoClient
from json import JSONEncoder
from bson.objectid import ObjectId
from functools import wraps


app = Flask(__name__)

mongo = MongoClient('localhost', 27017)

app.db = mongo.eventure_db

app.bcrypt_rounds = 12

api = Api(app)

# Authentication code.
def check_auth(username, password):
    # check_auth should access the database and check if the username +  password are correct.
    # create a collection to hold the users.

   user_collection = app.db.users
   user = user_collection.find_one({'username': username})

   if user is None:
        return False
    else:
        # check if hash generated matches stored hash
        encodedPassword = password.encode('utf-8')
        if bcrypt.hashpw(encodedPassword, user['password']) == user['password']:
            return True
        else:
            return False



# User resource

class User(Resource):

   def post(self):
        if (request.json['username'] == None
                or request.json['password'] == None):
                return ({'error':  'Request requires username and password'},
                    400,
                    None)

        user_collection = app.db.users
        user = user_collection.find_one({'username':       request.json['username']})

        if user is not None:
            return ({'error': 'Username already in use'}, 400, None)
        else:
            encodedPassword = request.json['password'].encode('utf-8')
            hashed = bcrypt.hashpw(
                encodedPassword, bcrypt.gensalt(app.bcrypt_rounds))
            request.json['password'] = hashed
            user_collection.insert_one(request.json)

    @requires_auth
    def get(self):
        return (None, 200, None)


api.add_resource(User, '/eventure/api/v1.1/user/')

# Must define a custom JSON Serializer for flask_restful
# this is because ObjectId is not a string, and therefore,
# Flask's default serializer cannot serialize it.

@api.representation('application/json')
def output_json(data, code, headers=None):

    resp = make_response(JSONEncoder().encode(data), code)
    resp.headers.extend(headers or {})
        return resp



if __name__ == '__main__':
    app.config['TRAP_BAD_REQUEST_ERRORS'] = True
    app.run(Host='localhost', port=8789, debug=True)

そしてこれはSwiftの私の登録機能です：

@IBAction func register(_ sender: AnyObject) {

    let url = URL(string: "http://localhost:8789/eventure/api/v1.1/user/")

    var request = URLRequest(url: url!)

    request.httpMethod = "POST"

    request.setValue(generateBasicAuthHeader(username: username.text!, password: password.text!), forHTTPHeaderField: "Authorization")


    let session = URLSession.shared

    let task = session.dataTask(with: request) { data, response, error in
        if let response = response, let data = data {
            print(String(data: data, encoding: String.Encoding.utf8))
        }
    }

    task.resume()




    self.username.text = ""
    self.password.text = ""



}

トレースバック：

  [28/Oct/2016 19:22:33] "POST /eventure/api/v1.1/user/ HTTP/1.1" 500 -
  Traceback (most recent call last):
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1820, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask_restful/__init__.py", line 270, in error_router
    return original_handler(e)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1403, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/_compat.py", line 32, in reraise
    raise value.with_traceback(tb)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1817, in wsgi_app
    response = self.full_dispatch_request()
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1477, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask_restful/__init__.py", line 270, in error_router
    return original_handler(e)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1381, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/_compat.py", line 32, in reraise
    raise value.with_traceback(tb)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1475, in full_dispatch_request
    rv = self.dispatch_request()
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/app.py", line 1461, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask_restful/__init__.py", line 471, in wrapper
    resp = resource(*args, **kwargs)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask/views.py", line 84, in view
    return self.dispatch_request(*args, **kwargs)
  File "/Users/Dynee/eventure-backend-api/development/lib/python3.5/site-packages/flask_restful/__init__.py", line 581, in dispatch_request
    resp = meth(*args, **kwargs)
  File "/Users/Dynee/eventure-backend-api/server.py", line 128, in post
    if (request.json['username'] == None
TypeError: 'NoneType' object is not subscriptable

また、generateBasicAuthHeader関数は次のとおりです。

func generateBasicAuthHeader(username: String, password: String) -> String {

    let loginString = String(format: "%@:%@", username, password)
    let loginData = loginString.data(using: String.Encoding.utf8)!
    let base64LoginString = loginData.base64EncodedString()
    let basicAuthHeader = "Basic \(base64LoginString)"
    return basicAuthHeader
}
pythonrestflaskflask-restful
5
Lucas Padden

_content-type_がフラスコ内で正しく機能するためには、_application/json_を_request.json_に明示的に設定する必要があります。ヘッダーが設定されていない場合、_request.json_はNoneを返します。

ただし、ポストリクエストからflask）でjsonデータを取得することをお勧めします request.get_json()

また、iosアプリケーションを使用する前に、気の利いた requests モジュールを使用してAPIをテストすることをお勧めします。

_>>> import requests
>>> requests.post(url, json={'name': 'hello world'})
_

jsonリクエストを行うために必要な適切なヘッダーがすでに設定されています

requestsモジュールで動作する場合は、iOSアプリケーションで動作することを確認できます。正しい_content-type_を設定していることを確認する必要があります。

flaskに_content-type_ヘッダーを無視するように強制的に指示できます。

request.get_json(force=True)

16
danidee