Synchronous AJAX call fail in Firefox

Open Beginner friendly

#46 opened on Feb 29, 2016 0 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 2/5
Estimated time: 1-3 hours
Newbie friendliness: 62/100

Issue type: Bug
Clarity: Clearly specified
Activity status: Stale
Tech stack: javascript
Domain: frontend, web-dev

Research direction

Start at dist/xhook.js around lines 451, 468, 487, and 517, following the synchronous send path in Firefox. Check the documented XMLHttpRequest withCredentials restriction for synchronous requests. Done means synchronous AJAX calls no longer throw this exception while the existing asynchronous behavior remains intact.

Written by the indexing model from the issue text.

Description

It fails with

A parameter or an operation is not supported by the underlying object
window[XMLHTTP]/facade.send/send@http://localhost:3000/dist/xhook.js:468:11
window[XMLHTTP]/facade.send/process@http://localhost:3000/dist/xhook.js:487:1
window[XMLHTTP]/facade.send@http://localhost:3000/dist/xhook.js:517:5
...

It fails on https://github.com/jpillora/xhook/blob/gh-pages/dist/xhook.js#L451 when you try to set withCredentails property to XHR object.

This seems to be a documented behavior.

According to https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest

Note: Starting with Gecko 11.0 (Firefox 11.0 / Thunderbird 11.0 / SeaMonkey 2.8), Gecko no longer lets you use the withCredentials attribute when performing synchronous requests. Attempting to do so throws an NS_ERROR_DOM_INVALID_ACCESS_ERR exception.

Dominant language: HTML
Stars: 1k
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