Python Flask 无法通过 CORS

Question

我有以下用python编写的脚本

from flask import Flask, request, jsonify
from flask_cors import CORS, cross_origin

app = Flask(__name__)
CORS(app, resources=r'/chat', headers='Content-Type')


@app.route("/chat")
def chat():
  print(request)
  request.get_data()
  data = json.loads(request.data)
  response = chatbot.get_response(str(data['message']))
  response_data = response.serialize()
  response = jsonify({'data': response_data})
  return response
app.run(host="0.0.0.0", port=8900, debug=True)

我从http://localhost:8080 上运行的 JavaScript 前端调用此 API

我正在使用谷歌浏览器并收到以下错误

Access to XMLHttpRequest at 'http://localhost:8900/chat/' from origin 'http://localhost:8080' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

对于每个请求，我还在 Python 控制台中收到以下日志消息

127.0.0.1 - - [19/Mar/2020 15:12:00] "?[33mOPTIONS /chat/ HTTP/1.1?[0m" 404 -

我真的很沮丧，因为即使我将代码更改为

@app.route("/chat")
def chat():
  print(request)
  request.get_data()
  data = json.loads(request.data)
  response = chatbot.get_response(str(data['message']))
  response_data = response.serialize()
  response = jsonify({'data': response_data})
  response.headers.add('Access-Control-Allow-Origin', '*')
  response.headers.add('Access-Control-Allow-Headers', 'append,delete,entries,foreach,get,has,keys,set,values,Authorization')
  response.headers.add('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE,OPTIONS')
  return response

我仍然遇到同样的错误。

Answer 1

您可以尝试这样设置标题吗？

from flask import Flask, request, jsonify
from flask_cors import CORS, cross_origin

app = Flask(__name__)
CORS(app, resources=r'/chat', headers='Content-Type')


@app.route("/chat")
def chat():
  print(request)
  request.get_data()
  data = json.loads(request.data)
  response = chatbot.get_response(str(data['message']))
  response_data = response.serialize()
  response = jsonify({'data': response_data})
  response.headers['Access-Control-Allow-Origin'] = '*'
  response.headers['Access-Control-Allow-Headers'] = 'append,delete,entries,foreach,get,has,keys,set,values,Authorization'
  response.headers['Access-Control-Allow-Methods'] = 'GET,PUT,POST,DELETE,OPTIONS'
  return response
app.run(host="0.0.0.0", port=8900, debug=True)