CSV PapaParse doesn't work for some links

Question

I'm using PapaParse for my CSV file with JavaScript. I'm able to use a CSV file from this website and using this link, which is the 5th one down. Everything works great using this link.

The problem arises when I download this file and then upload it to either github or one of my websites and then use that link instead. So basically, if I use the same file hosted on a different site the parser doesn't work. Any idea why?

Update:

Rawgit does work for github.com files but I still can't seem to parse CSV files from my website. It's just a link so I don't know why it wouldn't work. Thoughts?

Also, the first link above is from github.io. Why do CSV files that are on github.io work and not files from github.com or my website?

document.getElementById('submit').addEventListener("click", function() {
  checkLogin();
});

function checkLogin() {

  /* DOESN'T WORK */
  // "https://github.com/dhust/test/blob/master/Formaldehyde.csv"
  // "http://csfor.us/cs1/wp-content/uploads/2017/06/Formaldehyde.csv"

  /* WORKS */
  // "https://vincentarelbundock.github.io/Rdatasets/csv/datasets/Formaldehyde.csv"

  Papa.parse("https://vincentarelbundock.github.io/Rdatasets/csv/datasets/Formaldehyde.csv", {
    download: true,
    complete: function(results) {
      document.getElementById("output").innerHTML = results.data;
      console.log(results.data);
    }
  });
}

<script src="https://cdn.rawgit.com/mholt/PapaParse/3bf63f0a/papaparse.min.js"></script>
<input id="submit" type="button" value="Submit" />
<p id="output"></p>

Link to JSFiddle

Answer 1

Github doesn't allow direct downloading of files like that (see https://stackoverflow.com/a/4605068/320546).

Also for note, your Javascript console would have something like

XMLHttpRequest cannot load https://github.com/dhust/test/blob/master/Formaldehyde.csv. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'https://fiddle.jshell.net' is therefore not allowed access.

If however, you use RawGit you can get a link that should work, and indeed seems to be fine on JSFiddle