Best way to replace a file?

[suttercain]

Hi guys,

 

I have a file upload form and the file is moved and renamed based on the users id number. Example userId #150 = 150.jpg.

 

How can I allow the user to upload, using the same form, but replace the existing file so it will still read 150.jpg but with a new image (replacing the old one).

 

FORM

<form enctype="multipart/form-data" action="uploadedProfilePic" method="post">
<input name="logoImage" type="file"><br>
<input type="submit" name="submit" value="Submit">
</form>

 

PHP

<?php session_start(); //DO NOT REMOVE!!!! ?>
<?php if ($_SESSION['merchant'] == 1) { ?>
<?php
require('../database.php');
if ($_FILES['logoImage']['size'] < 250000) {
	if ($_FILES['logoImage']['type'] === "image/gif" || $_FILES['logoImage']['type'] === "image/jpg" || $_FILES['logoImage']['type'] === "image/jpeg") {
	$sqlImage = mysql_query("SELECT merchantId FROM merchants WHERE username = '".$_SESSION['user']."'") or die(mysql_error($connect));
	$image = mysql_fetch_row($sqlImage);
	$imageName = $image['0'];

	// PROCESS IMAGE
	$target_path = "../profileimages/";
	$target_path = $target_path . basename( $_FILES['logoImage']['tmp_name']); 
	$_FILES['logoImage']['tmp_name'];

	//MOVE THE IMAGE TO THUMBNAILS
	move_uploaded_file($_FILES['logoImage']['tmp_name'], $target_path);

	//EXPLODE TO RENAME IMAGE
	$fileName = $_FILES['logoImage']['name'];
	$broken = explode(".", $fileName);
	rename("../profileimages/".basename($_FILES['logoImage']['tmp_name'])."", "../profileimages/".$imageName."." .$broken[1]."");

	//Upload Image Name Into Table
	$update = mysql_query("UPDATE merchants SET profilePic='" .$imageName."." .$broken[1]. "' WHERE merchantId='".$imageName."'"		) or die(mysql_error());
	$_SESSION['message'] = "Logo Uploaded!";
	echo "<script type=\"text/javascript\">document.location.href='logged.php'</script>";
	} else {
	echo "The image file must be in .gif, .jpg or .jpeg format.";
	$passed = FALSE;
	}
} else {
echo "The file was too large!"; 
}

} else {
echo "You are not authorized to view this page."; }
?>

 

Thanks

[btherl]

See this warning here:

 

"If the destination file already exists, it will be overwritten."

 

The default behaviour is to replace the file.

[suttercain]

Hi Btherl,

 

Using the code above does not overwrite the file though. Is it because I rename the file after the move to the directory?

 

SC

[btherl]

Aha.  So is the problem you are having that the rename() fails when the destination file already exists?

[suttercain]

I believe so. This is what the current code does.

 

User Uploads > File is Moved to Directory > File is renamed based on the userId and the extension type (exp. jpg, gif).

 

When a user "re" uploads a photo nothing happens. The form seems to process but no "new" file is placed in the directory. Instead the old file stays the same.

 

 

SC

[suttercain]

Do you think it would be "safe" to delete the existing file, with unlink, before uploading the new file. In essence replacing the old file?

 

//find the file based on userId

$myFile = $row['fileName'];
$fh = fopen($myFile, 'w') or die("can't open file");
fclose($fh);

//Uplaod file code here

[chocopi]

Thats what I do for one of my pages

 

<?php

$old_file = 'avatars/'.$page_id.'.gif';
if(file_exists($old_file))
{
   unlink($old_file);
}
copy ($_FILES['avatar']['tmp_name'], "avatars/".$page_id.".".$file_extension) or die("Your avatar could not be copied correctly!");

?>

 

~ Chocopi

[suttercain]

Hey Chocopi,

 

Yeah I was thinking along those same lines. I will give it a shot tonight.

 

Thanks.

[btherl]

Before fixing the problem, it would be good to verify that it really is a problem   Check that rename() returns false (indicating failure to rename).  If that's the case, then chocopi's approach should work.  If you're ultra paranoid, you may want to make a backup of the file you're deleting, just in case.