The zftp package provides a convenient and feature-rich way to work with mainframe FTP servers, specifically designed for z/OS systems. It offers capabilities to interact with z/OS datasets, execute FTP commands tailored for mainframe operations, and handle mainframe-specific attributes and file transfer modes.

• FTP Session Management: Establish and manage FTP sessions with a mainframe server. Send commands to the server and handle the server's responses.

• File Transfer: Retrieve and upload files to/from the FTP server. The package supports both ASCII and binary transfer modes, and includes functions to handle end-of-line sequence conversions between different operating systems.

• FTP Commands: Implement various FTP commands specific to z/OS systems, including listing datasets, executing JES commands, managing site parameters, and handling passive mode connections.

• Dataset Management: Interact with z/OS datasets, including retrieving attributes, checking migration status, and verifying dataset size. The package also provides functions to handle different types of datasets, such as partitioned and sequential datasets.

• HFS Attributes: Handle HFS attributes, manage HFS datasets, and work with partitioned datasets. The package also provides functions to parse job records and details from the JES spool.

• Error Handling: Define a set of FTP return codes and provide functions to check the server's response against these codes. The package includes a custom error type for FTP return code errors, which includes the received and expected return codes and an error message.

To install the zftp package, use the following go get command:

go get gopkg.in/ro-ag/zftp.v1

Here are some of the most important functions provided by the zftp package:

• Open(hostname string) (*FTPSession, error): Open an FTP session to the specified hostname, returning a session instance for further operations.

• (*FTPSession) Login(username, password string) error: Log in to the FTP server using the provided username and password.

• (*FTPSession) Get(remoteFile, localFile string, transferType TransferType) error: Retrieve a file from the FTP server and store it locally, specifying the transfer type as ASCII or binary.

• (*FTPSession) Put(localFile, remoteFile string, transferType TransferType) error: Upload a local file to the FTP server, specifying the transfer type as ASCII or binary.

• (*FTPSession) List(remotePath string) ([]string, error): List files and directories at the specified remote path on the FTP server.

• (*FTPSession) ListDatasets(remotePath string) ([]hfs.Dataset, error): List z/OS datasets at the specified remote path, including dataset attributes.

• (*FTPSession) GetAndGzip(remoteFile, localFile string, transferType TransferType) error: Retrieve a file from the FTP server, compress it using gzip format, and store it locally in a single step.

Refer to the GoDoc for detailed documentation and more functions provided by the package.

Here's an example that demonstrates the basic usage of the zftp package:

package main

import (
	"fmt"
	"gopkg.in/ro-ag/zftp.v0"
)

func main() {
	// Open an FTP session to the mainframe server
	s, err := zftp.Open("example.com")
	if err != nil {
		fmt.Println("Failed to open FTP session:", err)
		return
	}

	// Log in to the FTP server
	err = s.Login("username", "password")
	if err != nil {
		fmt.Println("Failed to log in:", err)
		return
	}

	// Retrieve a file from the FTP server and store it locally
	err = s.Get("remote_file.txt", "local_file.txt", zftp.TypeAscii)
	if err != nil {
		fmt.Println("Failed to retrieve file:", err)
		return
	}

	// Retrieve and compress a file from the FTP server using gzip format
	err = s.GetAndGzip("remote_file.txt", "local_file.txt.gz", zftp.TypeAscii)
	if err != nil {
		fmt.Println("Failed to retrieve and compress file:", err)
		return
	}

	// Close the FTP session
	err = s.Close()
	if err != nil {
		fmt.Println("Failed to close FTP session:", err)
		return
	}

	fmt.Println("File retrieved and compressed successfully!")
}

The GetAndGzip function allows you to retrieve a file from the FTP server and compress it using gzip format in a single step. This can be beneficial in scenarios where you need to conserve bandwidth and storage space. By compressing the file during the retrieval process, you reduce the size of the transferred data, resulting in faster downloads and reduced storage requirements. The GetAndGzip function simplifies this process by handling the retrieval and compression in a single function call, streamlining your file transfer operations.

Contributions to the zftp package are welcome! Please open an issue to discuss any proposed changes or improvements.

The zftp package is licensed under the MIT License. See the LICENSE file for more information.