Hey everyone, I'm running into a CORS issue while attempting to load a script for testing using Fetch in my browser's dev tools. My instinct says this is probably a problem with the external script I'm trying to load, but I want to double-check. My Laravel website has a CORS configuration that should allow this, and I haven't encountered issues with scripts like Tag Manager or GA4 in the past. Here's my CORS configuration for reference:
```php
'allowed_origins' => ['*'],
```
The exact error I'm receiving is:
```
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at (SCRIPT I AM LOADING). (Reason: CORS header 'Access-Control-Allow-Origin' missing). Status code: 200.
```
So, is this CORS error something on my end, or is it an issue with the script's response?
3 Answers
Wildcards in allowed origins are a common misconception nowadays. Originally, they were a workaround, but recent changes require stricter handling. The browser first sends an OPTIONS request to check if the Access-Control-Allow-Origin header matches the origin of your site. If not, the request is blocked. Make sure the external script's server is handling CORS correctly—if they don’t send the right headers back, you’ll run into issues like this.
Also, it's worth noting that scripts like GA4 operate differently through `` tags, so they might not trigger the CORS checks in the same way as Fetch requests. If you're completely stuck, consider setting up a proxy on your backend to manage the request securely.
So yeah, your gut feeling seems right; it’s likely the external script’s CORS setup that’s causing the problem.
Exactly! When the server doesn’t provide the right CORS headers, fetch will fail regardless of your local setup. That’s why GA4 scripts can work without issues—they sidestep the fetch restrictions.
You're spot on about the 200 status code being misleading here. CORS errors happen when the right headers aren’t sent back, which isn't something the Laravel setup can fix since it only controls inbound requests, not outbound ones.
Double-check if the external server is providing the Access-Control-Allow-Origin header. If it’s not there, it’s definitely a server-side issue, not yours. But if you can share your fetch code, maybe we can spot something!
CORS issues can be tricky. It's essential to check if the header you need is present in the response. In your configuration, make sure there are no duplicate keys. Ensure that when you make a request, the Origin header matches what the server expects. If you're configuring CORS, confirm that it's active for the correct routes that you’re working with.
To add to that, if you can't control the script, your only real option left is the proxy approach. Just redirect the request through your backend, and then make a standard request to your frontend. It's a workaround but can save a lot of headaches!