Get most recent online file?

Processing Coding Questions
1

Imagine a public directory online, like this one: https://neo.sci.gsfc.nasa.gov/archive/rgb/MOD_LSTD_E/

This directory has a file put into it usually every 8 days. I would like to get the newest file whenever the sketch is run. Now I could simply check for a file added today, and then go backwards a day at a time for 8 days until I find something, but that technique is quite slow.

Does anyone know of a way to examine the creation dates of files in such a directory so that I might be able to find the newest one?

Thank you in advance!

2

Load the page’s source code which is plain html, extract file names and modification dates and loaded them into a map or some sort of data container so you can sort it.

Kf

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3

That’s a good tip, thank you kfrajer.

I’m seeing if I can shortcut that by loading the html into a string, scraping the files names (that’s all I really need) and then only saving the last one it finds, since that is the newest.

4

OK I think I got it.

This chore is made a little easier by the fact that the files are listed in chronological order.

String[] ln = loadStrings("https://neo.sci.gsfc.nasa.gov/archive/rgb/MOD_LSTD_E/");
String page1 = "";
int ignore; // lines of code to ignore at the top of the webpage

for (int i=0;i<ln.length;i++) {
    //println(i+" "+ln[i]); //print html with line numbers
    page1 = page1+=ln[i];
}

String[][] test = matchAll(page1, ">MOD_LSTD_E_(.*?).PNG</a>");

//print ALL values found
//for (int i = 0; i < ln.length-ignore; i++) {
  //ignore = 12;
  // print(i + " "); println(test[i][1]);
//}

//print only last (most recent) value
ignore = 13;
print(test[int(ln.length-ignore)][1]);
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