How to Send a File via cURL from a PHP Form POST?

Send File via cURL from Form POST in PHP

Handling file uploads from form posts is a common task in API development. This question explores how to send a file via cURL using a PHP script.

The HTML form includes a file upload input field:

<form action="script.php" method="post" enctype="multipart/form-data">
  <input type="file" name="image">
  <input type="submit" name="upload" value="Upload">
</form>

The server-side PHP script (script.php) first checks if the "upload" button was clicked:

if (isset($_POST['upload'])) {
  // Handle file upload with cURL
}

To send the file with cURL, we need to set the following parameters:

• CURLOPT_URL: The URL of the remote file upload destination
• CURLOPT_UPLOAD: 1 (Indicates that the request contains a file upload)
• CURLOPT_INFILE: The file pointer of the temporary file uploaded to the server
• CURLOPT_INFILESIZE: The size of the file in bytes

Here's a sample cURL code snippet that sends the file:

$localFile = $_FILES['image']['tmp_name']; 
$url = "https://example.com/file_upload.php";

$ch = curl_init($url);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, array('file' => '@' . $localFile);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$result = curl_exec($ch);
curl_close($ch);

On the receiving end, the script should handle the file upload and store it accordingly. Here's an example:

$file = $_FILES['file'];
$fileName = $file['name'];
$fileTmpName = $file['tmp_name'];
move_uploaded_file($fileTmpName, '/path/to/uploads/' . $fileName);

The above is the detailed content of How to Send a File via cURL from a PHP Form POST?. For more information, please follow other related articles on the PHP Chinese website!