Class Poco::Net::FTPClientSession
Author: Applied Informatics Software Engineering GmbH and Contributors

# Poco::Net

# class FTPClientSession

Library: Net
Package: FTP
Header: Poco/Net/FTPClientSession.h

## Description

This class implements an File Transfer Protocol (FTP, RFC 959) client.

Most of the features of the FTP protocol, as specified in RFC 959, are supported. Not supported are EBCDIC and LOCAL data types and format control and structured files.

Also supported are the EPRT and EPSV commands from RFC 1738 (FTP Extensions for IPv6 and NAT). The client will first attempt to use the EPRT and EPSV commands. If the server does not supports these commands, the client will fall back to PORT and PASV.

## Member Summary

Member Functions: abort, activeDataConnection, beginDownload, beginList, beginUpload, cdup, close, createDirectory, endDownload, endList, endTransfer, endUpload, establishDataConnection, extractPath, getFileType, getPassive, getTimeout, getWorkingDirectory, isLoggedIn, isOpen, isPermanentNegative, isPositiveCompletion, isPositiveIntermediate, isPositivePreliminary, isTransientNegative, login, logout, open, parseAddress, parseExtAddress, passiveDataConnection, remove, removeDirectory, rename, sendCommand, sendEPRT, sendEPSV, sendPASV, sendPORT, sendPassiveCommand, sendPortCommand, setFileType, setPassive, setTimeout, setWorkingDirectory, systemType

## Enumerations

### Anonymous

FTP_PORT = 21

### Anonymous

DEFAULT_TIMEOUT = 30000000

### FileType

TYPE_TEXT

TYPE_BINARY

### StatusClass

FTP_POSITIVE_PRELIMINARY = 1

FTP_POSITIVE_COMPLETION = 2

FTP_POSITIVE_INTERMEDIATE = 3

FTP_TRANSIENT_NEGATIVE = 4

FTP_PERMANENT_NEGATIVE = 5

## Constructors

### FTPClientSession

FTPClientSession();

Creates an FTPClientSession.

Passive mode will be used for data transfers.

### FTPClientSession

explicit FTPClientSession(
const StreamSocket & socket
);

Creates an FTPClientSession using the given connected socket for the control connection.

Passive mode will be used for data transfers.

### FTPClientSession

FTPClientSession(
const std::string & host,
Poco::UInt16 port = FTP_PORT,
const std::string & username = "",
const std::string & password = ""
);

Creates an FTPClientSession using a socket connected to the given host and port. If username is supplied, login is attempted.

Passive mode will be used for data transfers.

## Destructor

### ~FTPClientSession

virtual ~FTPClientSession();

Destroys the FTPClientSession.

## Member Functions

### abort

void abort();

Aborts the download or upload currently in progress.

Sends a TELNET IP/SYNCH sequence, followed by an ABOR command to the server.

A separate call to endDownload() or endUpload() is not necessary.

### beginDownload

std::istream & beginDownload(
const std::string & path
);

Starts downloading the file with the given name. After all data has been read from the returned stream, endDownload() must be called to finish the download.

A stream for reading the file's content is returned. The stream is valid until endDownload() is called.

Creates a data connection between the client and the server. If passive mode is on, then the server waits for a connection request from the client. Otherwise, the client waits for a connection request from the server. After establishing the data connection, a SocketStream for transferring the data is created.

If ASCII transfer mode is selected, the caller is responsible for converting the received data to the native text file format. The InputLineEndingConverter class from the Foundation library can be used for that purpose.

### beginList

std::istream & beginList(
const std::string & path = "",
bool extended = false
);

Starts downloading a directory listing. After all data has been read from the returned stream, endList() must be called to finish the download.

A stream for reading the directory data is returned. The stream is valid until endList() is called.

Optionally, a path to a directory or file can be specified. According to the FTP prototol, if a path to a filename is given, only information for the specific file is returned. If a path to a directory is given, a listing of that directory is returned. If no path is given, a listing of the current working directory is returned.

If extended is false, only a filenames (one per line) are returned. Otherwise, a full directory listing including file attributes is returned. The format of this listing depends on the FTP server. No attempt is made to interpret this data.

Creates a data connection between the client and the server. If passive mode is on, then the server waits for a connection request from the client. Otherwise, the client waits for a connection request from the server. After establishing the data connection, a SocketStream for transferring the data is created.

### beginUpload

std::ostream & beginUpload(
const std::string & path
);

Starts uploading the file with the given name. After all data has been written to the returned stream, endUpload() must be called to finish the download.

A stream for reading the file's content is returned. The stream is valid until endUpload() is called.

Creates a data connection between the client and the server. If passive mode is on, then the server waits for a connection request from the client. Otherwise, the client waits for a connection request from the server. After establishing the data connection, a SocketStream for transferring the data is created.

If ASCII transfer mode is selected, the caller is responsible for converting the data to be sent into network (CR-LF line endings) format. The OutputLineEndingConverter class from the Foundation library can be used for that purpose.

### cdup

void cdup();

Moves one directory up from the current working directory on teh server.

Sends a CDUP command to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### close

void close();

Sends a QUIT command and closes the connection to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### createDirectory

void createDirectory(
const std::string & path
);

Creates a new directory with the given path on the server.

Sends a MKD command with path as argument to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### endDownload

void endDownload();

Must be called to complete a download initiated with beginDownload().

### endList

void endList();

Must be called to complete a directory listing download initiated with beginList().

### endUpload

void endUpload();

Must be called to complete an upload initiated with beginUpload().

### getFileType

FileType getFileType() const;

Returns the file type for transferring files.

### getPassive

bool getPassive() const;

Returns true if and only if passive mode is enabled for this connection.

### getTimeout

Poco::Timespan getTimeout() const;

Returns the timeout for socket operations.

### getWorkingDirectory

std::string getWorkingDirectory();

Returns the current working directory on the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### isLoggedIn

bool isLoggedIn() const;

Returns true if the session is logged in.

### isOpen

bool isOpen() const;

Returns true if the connection with FTP server is opened.

### login

void login(
const std::string & username,
const std::string & password
);

Authenticates the user against the FTP server. Must be called before any other commands (except QUIT) can be sent.

Sends a USER command followed by a PASS command with the respective arguments to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### logout

void logout();

### open

void open(
const std::string & host,
Poco::UInt16 port,
const std::string & username = "",
const std::string & password = ""
);

Opens the FTP connection to the given host and port. If username is supplied, login is attempted.

### remove

void remove(
const std::string & path
);

Deletes the file specified by path on the server.

Sends a DELE command with path as argument to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### removeDirectory

void removeDirectory(
const std::string & path
);

Removes the directory specified by path from the server.

Sends a RMD command with path as argument to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### rename

void rename(
const std::string & oldName,
const std::string & newName
);

Renames the file on the server given by oldName to newName.

Sends a RNFR command, followed by a RNTO command to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### sendCommand

int sendCommand(
const std::string & command,
std::string & response
);

Sends the given command verbatim to the server and waits for a response.

### sendCommand

int sendCommand(
const std::string & command,
const std::string & arg,
std::string & response
);

Sends the given command verbatim to the server and waits for a response.

### setFileType

void setFileType(
FileType type
);

Sets the file type for transferring files.

Sends a TYPE command with a corresponsing argument to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### setPassive

void setPassive(
bool flag,
bool useRFC1738 = true
);

Enables (default) or disables FTP passive mode for this session.

If useRFC1738 is true (the default), the RFC 1738 EPSV command is used (with a fallback to PASV if EPSV fails) for switching to passive mode. The same applies to EPRT and PORT for active connections.

### setTimeout

void setTimeout(
const Poco::Timespan & timeout
);

Sets the timeout for socket operations.

### setWorkingDirectory

void setWorkingDirectory(
const std::string & path
);

Changes the current working directory on the server.

Sends a CWD command with the given path as argument to the server.

Throws a FTPException in case of a FTP-specific error, or a NetException in case of a general network communication failure.

### systemType

std::string systemType();

Returns the system type of the FTP server.

Sends a SYST command to the server and returns the result.

### activeDataConnection

StreamSocket activeDataConnection(
const std::string & command,
const std::string & arg
);

### endTransfer

void endTransfer();

### establishDataConnection

StreamSocket establishDataConnection(
const std::string & command,
const std::string & arg
);

### extractPath

std::string extractPath(
const std::string & response
);

### isPermanentNegative

static bool isPermanentNegative(
int status
);

### isPositiveCompletion

static bool isPositiveCompletion(
int status
);

### isPositiveIntermediate

static bool isPositiveIntermediate(
int status
);

### isPositivePreliminary

static bool isPositivePreliminary(
int status
);

### isTransientNegative

static bool isTransientNegative(
int status
);

### parseAddress

void parseAddress(
const std::string & str,
SocketAddress & addr
);

### parseExtAddress

void parseExtAddress(
const std::string & str,
SocketAddress & addr
);

### passiveDataConnection

StreamSocket passiveDataConnection(
const std::string & command,
const std::string & arg
);

### sendEPRT

bool sendEPRT(
const SocketAddress & addr
);

### sendEPSV

bool sendEPSV(
SocketAddress & addr
);

### sendPASV

void sendPASV(
SocketAddress & addr
);

### sendPORT

void sendPORT(
const SocketAddress & addr
);

### sendPassiveCommand

SocketAddress sendPassiveCommand();

### sendPortCommand

void sendPortCommand(
const SocketAddress & addr
);