afraid-scarlet•9mo ago

cors

@kapa.ai Access to fetch at 'rest 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.

2 Replies

kapa.ai•9mo ago

Hi @h_perx. I'm kapa.ai, your friendly support bot. I will try to answer your question by searching through the knowledge base. :wave: ---------------------- The error message you're seeing is related to Cross-Origin Resource Sharing (CORS), which is a security feature that restricts how resources on a web page can be requested from another domain. In your case, it seems like the server of your REST API is not set up to accept requests from the origin 'http://localhost:3000/'. To resolve this issue, you need to configure your server to include the 'Access-Control-Allow-Origin' header in its responses, and this header should include the origin 'http://localhost:3000/'. If you're testing your application and you have control over the server, you can temporarily allow all origins by setting 'Access-Control-Allow-Origin' to ''. However, this is not recommended for production environments due to security concerns. Here's an example of how you can set this header in an Express.js server: ```javascript app.use((req, res, next) => { res.header('Access-Control-Allow-Origin', ''); next(); });

If you're using a third-party API, you might not have the ability to change the server's CORS policy. In this case, you could create a proxy server that adds the necessary headers.

Please note that this is a general solution and might not work in all cases. The exact solution might depend on the specifics of your server or API.

If you're using the `fetch` method in your refine application to make requests to your API, you might also need to include the 'mode' option with the value 'cors':

If you're using a third-party API, you might not have the ability to change the server's CORS policy. In this case, you could create a proxy server that adds the necessary headers.

Please note that this is a general solution and might not work in all cases. The exact solution might depend on the specifics of your server or API.

If you're using the `fetch` method in your refine application to make requests to your API, you might also need to include the 'mode' option with the value 'cors':

javascript fetch('https://api.example.com', { mode: 'cors', }) ``` Please note that this is a general solution and might not work in all cases. The exact solution might depend on the specifics of your server or API. For more information on CORS, you can check out the MDN Web Docs (https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS). If you're still having trouble, please provide more details about your server setup and the exact request you're trying to make. ---------------------- Note: you can ask me a follow up question by @ mentioning me again :speech_balloon: ----------------------

kapa.ai•9mo ago

<@539536201053503499> kapa.ai is still learning and improving, please let us know how it did by reacting below