New version

Added better error handling and exception throwing for critical parts.
Used array syntax for defining options array for readability.
Cleaned up redundant checks and improved comments for clarity.
Enhanced method names and parameter names for better understanding.
Added error handling for file operations like opening local files for writing.
Improved readability and formatting for better code maintainability

Author: nalindaDJ

FTP_Implicit_SSL.php

@@ -0,0 +1,180 @@
+<?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);
+    }
+}
+?>