php

PHP remember file field contents

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I have a form with text inputs and file inputs; the text fields are being validated. Is there a way to have the form remember which files the user has already selected if they hit submit but need to go back because one of the text fields didn't validate?

Answers

You can't "pre-fill" the contents of a file upload field for security reasons. Also, that would mean the file would get re-uploaded every time the form is submitted, which would not be good.

Instead, do this:

Create a file upload field with name file_upload.
On the server-side, process the upload in any case, even if the rest of the form validation fails.
If the form validation failed, but the file was uploaded, insert a hidden input into the form with name file containing the name of the just uploaded file.
Display a user-visible indication that the file is okay. If it's an image, display a thumbnail version of it. If it's any other file, display its filename and/or icon.
If the user chooses to upload a different file in the file_upload field, process the upload and store the new value in file.

Pseudocode:

<?php
    $file = null;
    if (!empty($_POST['file'])) {
        $file = $_POST['file'];
    }
    if (!empty($_FILES['file_upload'])) {

        // process upload, save file somewhere

        $file = $nameOfSavedFile;
    }

    // validate form
?>


<input type="file" name="file_upload" />
<input type="hidden" name="file" value="<?php echo $file; ?>" />
<?php
    if (!empty($file)) {
        echo "File: $file";
    }
 ?>

Important note

This mechanism can allow any user to claim other user's files as their own, by including a file name that they guessed exists on your server. You will want to ensure that uploaded files are clearly associated with a specific user to avoid this issue.

Saturday, December 10, 2022

65laborde-29b5950e765a

A few years ago I benchmarked the two and CURL was faster. With CURL you create one CURL instance which can be used for every request, and it maps directly to the very fast libcurl library. Using file_get_contents you have the overhead of protocol wrappers and the initialization code getting executed for every single request.

I will dig out my benchmark script and run on PHP 5.3 but I suspect that CURL will still be faster.

Friday, December 16, 2022

primenumbers

In your url try:

http://user:password@site/

(append whatever the rest of the URL for your API should be)

Friday, November 4, 2022

matoran

Here's what worked best for me when trying to script this (in case anyone else comes across this like I did):

$ pecl -d php_suffix=5.6 install <package>
$ pecl uninstall -r <package>

$ pecl -d php_suffix=7.0 install <package>
$ pecl uninstall -r <package>

$ pecl -d php_suffix=7.1 install <package>
$ pecl uninstall -r <package>

The -d php_suffix=<version> piece allows you to set config values at run time vs pre-setting them with pecl config-set. The uninstall -r bit does not actually uninstall it (from the docs):

vagrant@homestead:~$ pecl help uninstall
pecl uninstall [options] [channel/]<package> ...
Uninstalls one or more PEAR packages.  More than one package may be
specified at once.  Prefix with channel name to uninstall from a
channel not in your default channel (pecl.php.net)

Options:
  ...
  -r, --register-only
        do not remove files, only register the packages as not installed
  ...

The uninstall line is necessary otherwise installing it will remove any previously installed version, even if it was for a different PHP version (ex: Installing an extension for PHP 7.0 would remove the 5.6 version if the package was still registered as installed).

Monday, December 12, 2022

shankar_damodaran

Never used any of those, but they look interesting..

Take a look at Gearman as well.. more overhead in systems like these but you get other cool stuff :) Guess it depends on your needs ..

Friday, November 11, 2022

the_falvert

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