Сеанс Flask не сохраняется (Postman работает, Javascript — нет) ⇐ Python

[Гость]

Я разрабатываю сервер Flask для взаимодействия между некоторыми внутренними функциями Python и клиентами Javascript через Интернет. Я пытаюсь использовать Flask

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session

variable to store user specific data over the course of their time interacting with the app. I've removed most of the application specific code below but the core problem I'm experiencing remains.

Here is my the code for my (simplified) Flask app:

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import json
import os
from flask import Flask, jsonify, request, session

app = Flask(__name__)
app.secret_key = 'my_secret_key'

@app.route('/', methods=['GET'])
def run():
session['hello'] = 'world'
return jsonify(session['hello'])

@app.route('/update', methods=['POST'])
def update():
return jsonify(session['hello'])

if __name__ == '__main__':
app.run(host='0.0.0.0')

Utilizing Postman, I can make a GET request to my server and receive the expected output of

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"world"

. I can then make a POST request with an arbitrary body and receive the same expected output of

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"world"

(again using Postman).

When using Chrome, I can visit my server IP and see the expected output

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"world"

on the page. I can also manually make a GET request using Javascript (in Chrome's console) and receive the same response as expected. However, my problem arises when trying to send a POST request to the server using Javascript; the server shows a

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KeyError: 'hello'

when trying to make this request.

Here is the Javascript I'm using to make the POST request:

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var url = 'http://my_server_ip/update';
fetch(url, {
method: 'POST',
body: JSON.stringify('arbitrary_string'),
headers: new Headers({
'Content-Type': 'application/json'
})
})
.then(response => response.json())
.then((data) => {
console.log(data);
})

What's going wrong here? Why can I make the GET/POST requests with Postman just fine but run into errors making the same requests with Javascript?


Источник: https://stackoverflow.com/questions/497 ... ipt-doesnt