Flask-CORS does not work for POST, but works for GET

Question

I run the Flask-Restful API locally and send a POST request containing JSON from another port. I get an error

No 'Access-Control-Allow-Origin' header is present on the requested resource.

However, when I run

curl --include -X OPTIONS http://localhost:5000/api/comments/3
        --header Access-Control-Request-Method:POST
        --header Access-Control-Request-Headers:Content-Type
        --header Origin:http://localhost:8080

I get

HTTP/1.0 200 OK
Content-Type: text/html; charset=utf-8
Allow: HEAD, GET, POST, OPTIONS
Access-Control-Allow-Origin: http://localhost:8080
Access-Control-Allow-Methods: DELETE, GET, HEAD, OPTIONS, PATCH, POST, PUT
Vary: Origin
Access-Control-Allow-Headers: Content-Type
Content-Length: 0

which shows "Access-Control-Allow-Origin" as "*". GET is working fine, it's just a POST that gives this error. What could go wrong? If necessary, for the interface I use reaction and query through axioms.

Answer 1

You need to add CORS(app, resources={r"/*": {"origins": "*"}})to your flash application.

Hope that solves the problem.

Answer 2

Flask-Cors ,

" JSON OPTIONS POST. POST JSON, Content-Type. : CORS_HEADERS : , "

https://flask-cors.readthedocs.io/en/1.9.0/

app.config['CORS_HEADERS'] = 'Content-Type'