Flask-CORS
実験的な機能をFlaskでサーバ立てて実験しようとした時に、そのサーバのAPIを別のサーバに置かれたコンテンツのJSで読み込もうとするとCORS policyでブロックされる。
:Access to fetch at 'http://localhost:5000/api/' from origin 'http://localhost:3000' 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. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.サーバサイド
diff from flask import Flask
+ from flask_cors import CORS
app = Flask(__name__)
+ CORS(app)クライアントサイド
diff fetch("http://localhost:5000/api/", {
+ mode: "cors",
method: "POST",
body: JSON.stringify(data),
headers: {
"Content-Type": "application/json",
},
}).then((response) => {"Content-Type": "application/json"で叩いてるのでFlaskの側ではjsonで受ける
これを忘れてて400 Bad Requestになった
原因は末尾のスラッシュ
"Engineer's way of creating knowledge" the English version of my book is now available on [Engineer's way of creating knowledge]
(C)NISHIO Hirokazu / Converted from [Scrapbox] at [Edit]