FTP_Implicit_SSL.php

<?php
/**
 * FTP with Implicit SSL/TLS Class
 *
 * Simple wrapper for cURL functions to transfer an ASCII file over FTP with implicit SSL/TLS
 *
 * @category    Class
 * @author      Damith Jayasinghe
 * @since       1.8
 */

class FTP_Implicit_SSL {

    /** @var resource cURL resource handle */
    private $curl_handle;

    /** @var string cURL URL for upload */
    private $url;

    /**
     * Connect to FTP server over Implicit SSL/TLS
     *
     * @param string $username
     * @param string $password
     * @param string $server
     * @param int $port
     * @param string $initial_path
     * @param bool $passive_mode
     * @throws Exception
     */
    public function __construct($username, $password, $server, $port = 990, $initial_path = '', $passive_mode = false) {

        // Check for blank username, password, and server
        if (empty($username) || empty($server)) {
            throw new Exception('FTP Username or Server is blank.');
        }

        // Set host/initial path
        $this->url = "ftps://{$server}/{$initial_path}";

        // Initialize cURL handle
        $this->curl_handle = curl_init();

        // Check for successful connection
        if (!$this->curl_handle) {
            throw new Exception('Could not initialize cURL.');
        }

        // Connection options
        $options = [
            CURLOPT_USERPWD        => "$username:$password",
            CURLOPT_SSL_VERIFYPEER => false, // Don't verify SSL
            CURLOPT_SSL_VERIFYHOST => false,
            CURLOPT_FTP_SSL        => CURLFTPSSL_ALL, // Require SSL for both control and data connections
            CURLOPT_FTPSSLAUTH     => CURLFTPAUTH_DEFAULT, // Let cURL choose the FTP authentication method (either SSL or TLS)
            CURLOPT_UPLOAD         => true,
            CURLOPT_PORT           => $port,
            CURLOPT_TIMEOUT        => 30,
        ];

        // Enable active mode if passive mode is disabled
        if (!$passive_mode) {
            $options[CURLOPT_FTPPORT] = '-';
        }

        // Set connection options individually to catch errors
        foreach ($options as $option_name => $option_value) {
            if (!curl_setopt($this->curl_handle, $option_name, $option_value)) {
                throw new Exception("Could not set cURL option: $option_name");
            }
        }
    }

    /**
     * Upload file to FTP server
     *
     * @param string $file_name
     * @param string $file
     * @throws Exception
     */
    public function upload($file_name, $file) {
        // Set file name
        if (!curl_setopt($this->curl_handle, CURLOPT_URL, $this->url . $file_name)) {
            throw new Exception("Could not set cURL file name: $file_name");
        }

        // Open memory stream for writing
        $stream = fopen('php://temp', 'w+');

        // Check for valid stream handle
        if (!$stream) {
            throw new Exception('Could not open php://temp for writing.');
        }

        // Write file into the temporary stream
        fwrite($stream, $file);

        // Set the file to be uploaded
        curl_setopt($this->curl_handle, CURLOPT_INFILE, $stream);

        // Upload file
        if (!curl_exec($this->curl_handle)) {
            throw new Exception(sprintf('Could not upload file. cURL Error: [%s] - %s', curl_errno($this->curl_handle), curl_error($this->curl_handle)));
        }

        // Close the stream handle
        fclose($stream);
    }

    /**
     * Get list of files on FTP server
     *
     * @return array
     * @throws Exception
     */
    public function ftpfilelist() {
        curl_setopt($this->curl_handle, CURLOPT_URL, $this->url);
        curl_setopt($this->curl_handle, CURLOPT_UPLOAD, false);
        curl_setopt($this->curl_handle, CURLOPT_FTPLISTONLY, 1);
        curl_setopt($this->curl_handle, CURLOPT_RETURNTRANSFER, 1);
        $result = curl_exec($this->curl_handle);
        if ($result === false) {
            throw new Exception("Failed to retrieve file list. Error: " . curl_error($this->curl_handle));
        }
        return explode("\n", trim($result));
    }

    /**
     * Download file from FTP server
     *
     * @param string $file_name
     * @param string $local_path
     * @return string
     * @throws Exception
     */
    public function download($file_name, $local_path = '/') {
        $file = fopen("$local_path$file_name", "w");
        if (!$file) {
            throw new Exception("Failed to open local file for writing: $local_path$file_name");
        }
        curl_setopt($this->curl_handle, CURLOPT_URL, $this->url . $file_name);
        curl_setopt($this->curl_handle, CURLOPT_UPLOAD, false);
        curl_setopt($this->curl_handle, CURLOPT_FOLLOWLOCATION, 1);
        curl_setopt($this->curl_handle, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($this->curl_handle, CURLOPT_FILE, $file);
        if (!curl_exec($this->curl_handle)) {
            throw new Exception(sprintf('Failed to download file. cURL Error: [%s] - %s', curl_errno($this->curl_handle), curl_error($this->curl_handle)));
        }
        fclose($file);
        return "Download successful: $file_name";
    }

    /**
     * Get remote file size
     *
     * @param string $file_name
     * @return int
     * @throws Exception
     */
    public function remote_file_size($file_name) {
        curl_setopt($this->curl_handle, CURLOPT_URL, $this->url . $file_name);
        curl_setopt($this->curl_handle, CURLOPT_UPLOAD, false);
        curl_setopt($this->curl_handle, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($this->curl_handle, CURLOPT_HEADER, true);
        curl_setopt($this->curl_handle, CURLOPT_NOBODY, true);
        $data = curl_exec($this->curl_handle);
        if ($data === false) {
            throw new Exception("Failed to get remote file size for: $file_name. Error: " . curl_error($this->curl_handle));
        }
        return curl_getinfo($this->curl_handle, CURLINFO_CONTENT_LENGTH_DOWNLOAD);
    }

    /**
     * Close cURL handle
     */
    public function __destruct() {
        curl_close($this->curl_handle);
    }
}
?>