Firefox Upload Form Issue

Question

I've created an upload script in php that takes a file, resizes it, and creates a cropped square thumbnail. The script itself seems to work fine.

However, when I tried to upload an image through Firefox, on clicking the submit button the browser shows the loading animation, but it never calls the script, it just stays on the current page. If don’t upload an image, then the script can be found and is run.

I tried in safari, and I don’t get the same problem, I can upload an image from the form, it will process it and take me the correct page.

I’ve tired just calling a basic script from the form, it just prints out the $_POST and $_FILES, and I get the same result, if an image is present, it won’t get to the script, if no image is present, it runs fine.

I’m just wondering if anyone has any idea what’s going on?

=Update=

Okay, so I’ve still got this problem, I seem to think I’ve found out what’s causing it then, but then I find something that contradicts it completely.

At the moment, I’ve noticed that I can successfully upload after I clear my Firefox cache, but I can only upload one image, then when I try to upload another, I can’t, it just resets the connection after "Loading..." for a bit.

Also, I’ve noticed that I can Ctrl+F5 a few times and get another upload through.

Although there are ways around this, I don’t want to have a form that requires users to clear cookies or refresh every time they need to upload. And as I’ve mentioned before, this error does not occur in IE/Opera/Safari/Chrome.

It seems like Firefox is storing something, I’m not sure what. Any help would be gratefully appreciated.

If it helps here is the code I’m using.

The HTML Form

<form enctype="multipart/form-data" action="<?php echo $_SERVER["PHP_SELF"]; ?>" method="POST">
<label for="file">Choose a file to upload</label>
<input id="file" name="file" type="file" /><br />
<input type="submit" value="Upload File" name="submit" />

And the PHP:

if (isset($_POST['submit'])) {

  echo "Processing...<br/>";

  if (isset($_FILES['file']['name'])) {
      $file_array = $_FILES['file'];

      echo "Uploading...";
      upload File($file_array);
      echo "...Done";

  }
}

The echos are for me to see what’s going on. If none of them are actually being output. So for some reason the form is not being submitted. Which is why it’s not getting to the script. I’ve no idea why though. I’ve got no CSS, or JavaScript errors.

== Update ==

Okay I’ve being trying some more things and still no luck, the HTML, CSS and JavaScript is all valid. I’ve done an IIS Reset, I’ve recreated my Firefox profile. And still now luck.

I was testing it again, and this time I stopped it in the middle of loading (before the connection was reset) and then tried to go to a different page of the website, and the freezing continued, it would still say "Loading..." and "Waiting for localhost...". Not really sure what to make of that, is it some settings that I have? But then why doesn’t it affect other browsers?

== Update ==

As I mentioned below, it seems that AVG Linkscanner/Active surf shield seems to causing this issue, and there are many reports of others having similar problems with it. I updated from AVG Free v9.0.733 to v9.0.790 and I STILL have the same problem. I’m going to browse the AVG support forums and maybe post something over there since it seems to be an AVG issue.

If anyone does have any more insight, please post below. It’s much appreciated :)

Answer 1

Maybe shomething wrong with if (isset($_POST['submit'])) { and the variable $_POST['submit'] is not included by FireFox?

<pre>
    <?PHP
        print_r($_POST);
    ?>
</pre>

Answer 2

Just in case you are using the latest FF 3.6 I'm experiencing exactly the same problem, Any form loading a big file (1MB it's enought) seem to block FF upload. On IE7/Safari/Opera it works.

Answer 3

Sometimes, relative paths are perceived differently by different browsers, not that sure actually but try to specify current directory by prefixing path with ./, eg:

$target_path = "./public/photos/";

Rest of the code looks fine to me.

Answer 4

Then when you right click in FF and view source, it should look exactly like it does in your code above (below "If i have the correct tags like..").

Answer 5

This isn't going to help you much but I am having EXACTLY the same problem. I have even re-installed FF, cleared cache, stripped the code right down (to a very simple form without validation and with all PHP stripped out - both on load and on post back). I have the problem in FF 3.6.13 and have tested against current versions of Safari(win), Chrome, Opera and IE where the code all works perfectly. My code validates as strict XHTML and all the suggestions above are already in there... what's more I am using my local (on the same computer) web site.

MANY thanks for pointing me towards AVG Link scanner... disabling it does fix the problem but that still leaves me thinking FF has a bug as "all" other browsers play nicely with the AVG Link scanner on.

Answer 6

From the xhtml 1.0 specification

HTML 4 defined the name attribute for the elements a, applet, form, frame, iframe, img, and map. HTML 4 also introduced the id attribute. Both of these attributes are designed to be used as fragment identifiers.

In XML, fragment identifiers are of type ID, and there can only be a single attribute of type ID per element. Therefore, in XHTML 1.0 the id attribute is defined to be of type ID. In order to ensure that XHTML 1.0 documents are well-structured XML documents, XHTML 1.0 documents MUST use the id attribute when defining fragment identifiers on the elements listed above.

Maybe adding an id to the form could fix your problem.