How to Fix 'Cross-Origin Request Blocked' Errors in Firefox OS Apps?

Cross-Origin Request Blocked: Resolving Firefox OS Issue

The "Cross-Origin Request Blocked" error occurs when a browser restricts requests from a different origin due to security concerns. To resolve this issue in the context of a Firefox OS app, modifications to both your Go backend and JavaScript code are required.

Go Backend Modification:

Ensure that your Go handler sets the "Access-Control-Allow-Origin" header to "*" to allow requests from all origins:

func handleMessageQueue(w http.ResponseWriter, r *http.Request) {
    w.Header().Set("Access-Control-Allow-Origin", "*")
    // ... remainder of the code
}

JavaScript Modification:

1. Use mozSystem:

When creating the XMLHttpRequest object, specify the "mozSystem" flag as true:

var xhr = new XMLHttpRequest({mozSystem: true});

2. Add Permissions to Manifest:

In your Firefox OS app manifest, add the "systemXHR" permission under "permissions":

"permissions": {
       "systemXHR" : {},
}

Explanation:

mozSystem allows cross-site connections without CORS permission from the server. However, it is only available to privileged apps that pass the Firefox App Store's review process. The "systemXHR" permission in the manifest enables the use of mozSystem in your app.

By making these changes, you enable your Firefox OS app to initiate cross-origin requests to your Go backend and receive the necessary response data without being blocked by the Same Origin Policy.

The above is the detailed content of How to Fix 'Cross-Origin Request Blocked' Errors in Firefox OS Apps?. For more information, please follow other related articles on the PHP Chinese website!