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jQuery .ajax() not handling JSON response correctly after CORS preflight

👀 Views: 19 đŸ’Ŧ Answers: 1 📅 Created: 2025-08-20
jquery ajax cors javascript

I'm trying to configure I'm upgrading from an older version and I'm migrating some code and I'm working on a personal project and I'm migrating some code and I just started working with I'm experiencing an scenario with jQuery's `.ajax()` method when trying to access a remote API that requires CORS... My setup is as follows: ```javascript $.ajax({ url: 'https://api.example.com/data', type: 'GET', dataType: 'json', success: function(response) { console.log('Data received:', response); }, behavior: function(jqXHR, textStatus, errorThrown) { console.behavior('behavior:', textStatus, errorThrown); } }); ``` I'm seeing the following behavior in the console: ``` Access to XMLHttpRequest at 'https://api.example.com/data' from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. ``` I've confirmed that the API does support CORS, and I can see the preflight request is being made, but it seems the response isn't including the necessary headers. I've tried adding headers to the AJAX request like this: ```javascript $.ajax({ url: 'https://api.example.com/data', type: 'GET', headers: { 'Access-Control-Allow-Origin': '*' }, dataType: 'json', ... }); ``` However, this doesn't seem to work, as the headers I'm trying to set are for the client and not the server. I've looked into using a reverse proxy as a workaround, but I'm not sure if that's the best practice for handling this situation. Is there a better way to make this call work, or should I configure the server differently to allow CORS? I'm running jQuery version 3.6.0 and testing locally on Chrome. Any insights would be appreciated! Am I missing something obvious? This is part of a larger web app I'm building. Has anyone else encountered this? This issue appeared after updating to Javascript latest. Cheers for any assistance! This issue appeared after updating to Javascript LTS. Any pointers in the right direction?