All right. For the sake of the article, I will look at this error one more time:

Here I was, innocent developer that I am, just trying to make an innocent AJAX request to retrieve some innocent data from the ArcGIS Hub at Esri. I was playing around with my Esri developer account and I wanted to use some clean, location-based data, and there aren’t too many places better than the Hub.

(This was not intended to be an Esri advertisement, but honestly, check the site out. Tons of free materials, APIs and SDKs for JavaScript, Python, Java, and mobile…

This was not the article I intended to write.

I intended to write a quick-fix article about a CORS conflict that was ruining my day(s), and I began by introducing the concepts of same-origin-policy and CORS… and then it turned into this full-length article you see before you, and I hadn’t even begun to address the issue. I cover the issue here, but I think it’s nice to get an idea of what we’re working with before we start doing tweaks.

And therefore, I bring you the origin story of web content origin, and the hero that loved it.

Content Origin


I won’t lie to you. I’m very new to software development. If my coding journey from newbie to professional were a human’s journey to adulthood, I would be roughly in my awkward teenage years. And honestly, I would still be learning to crawl if it weren’t for the folks at Fullstack Academy, who have taken me from ‘Hello World’ to creating entire full-stack web applications in a little under six weeks. (During week two I had spent so much time coding I actually thought I broke my eyes.)

I still have a lot to learn, but my main takeaway has…

Dan Tracy

Software developer specializing in JavaScript/Node, React, Express, and Postgres. Other interests include GIS, data viz, and the piano. Looking for a good job!

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