PHP主机文件上传路径设置及权限、大小限制等问题咨询

Hey there! Let's work through your file upload issues step by step—here's a breakdown of each question:

1. Where should I create the staging/ folder? #

Your code uses a relative path ("staging/".time().$file_name), which means the folder needs to be in the same directory as your hola.php script.

For example:

• If your hola.php lives at public_html/hola.php (the standard web root for most hosts), create staging/ at public_html/staging/.
• If you want to keep uploaded files hidden from public access (more secure), you can create staging/ outside the web root (e.g., /home/your_username/staging/) and adjust the path to ../staging/. Just make sure your PHP script has permission to write to that location.

2. Do I need to set folder permissions? #

Absolutely! The web server (running as a user like www-data, apache, or nobody) needs write access to the staging/ folder to save uploaded files.

Here's how to set it:

• Use your FTP client: Right-click the staging/ folder, select "File Permissions," and set it to 755 (read/write/execute for owner, read/execute for others) or 775 (if you're on a shared host and need group write access). Avoid 777—it's a major security risk.
• Via SSH: Run the command chmod 755 staging/.

3. Are there limits for large file uploads? #

Yes, PHP and your web host impose default limits. You'll need to adjust these settings if you're uploading files larger than a few MB:

Key PHP configuration values: #

• upload_max_filesize: Maximum size for a single uploaded file.
• post_max_size: Maximum total size of all POST data (including files).
• max_execution_time: How long PHP allows the script to run.
• max_input_time: How long PHP waits to receive POST data.

How to adjust them: #

• Apache hosts: Add these lines to your .htaccess file in the web root:

  php_value upload_max_filesize 64M
  php_value post_max_size 64M
  php_value max_execution_time 300
  php_value max_input_time 300
  

• Nginx or shared hosts: Add these lines to a .user.ini file in the web root:

  upload_max_filesize = 64M
  post_max_size = 64M
  max_execution_time = 300
  max_input_time = 300
  

If these changes don't work, check with your host—they might have a hard limit you can't exceed.

4. Is the path separator / correct? #

Yes! PHP handles / as a valid path separator on both Windows and Linux servers, so your code is fine. You don't need to use Windows' native \ separator—PHP will automatically translate it for the server's OS.

5. What's a typical virtual host directory structure? #

Most shared hosts use a structure like this (rooted at /home/your_username/):

• public_html/ (or www/): The web-accessible root folder—all your public scripts (like hola.php) and assets go here.
• logs/: Stores server access logs and error logs (great for debugging upload issues).
• tmp/: The temporary directory where PHP stores uploaded files before you move them to staging/.
• mail/: Contains email-related files and settings.
• private/ (optional): A non-web-accessible folder for storing sensitive data (like uploaded files you don't want public).

Quick Debug Tip: #

Add error checking to your move_uploaded_file call to see if uploads are failing and why:

$targetPath = "staging/".time().$file_name;
if (!move_uploaded_file($file_tmp, $targetPath)) {
    echo "Failed to upload file: ".$file_name."<br>";
    // Optional: Print debug info
    echo "Error: ".error_get_last()['message']."<br>";
}

内容的提问来源于stack exchange，提问作者German Estrada Pacheco