CopperSpice API
1.9.2
|
The QFtp class provides an implementation of the client side of FTP protocol. More...
Public Types | |
enum | Command |
enum | Error |
enum | State |
enum | TransferMode |
enum | TransferType |
Public Signals | |
void | commandFinished (int id, bool error) |
void | commandStarted (int id) |
void | dataTransferProgress (qint64 done, qint64 total) |
void | done (bool error) |
void | listInfo (const QUrlInfo &urlInfo) |
void | rawCommandReply (int replyCode, const QString &detail) |
void | readyRead () |
void | stateChanged (int state) |
Public Signals inherited from QObject | |
void | destroyed (QObject *obj=nullptr) |
void | objectNameChanged (const QString &objectName) |
Public Slots | |
void | abort () |
Public Slots inherited from QObject | |
void | deleteLater () |
Public Methods | |
QFtp (QObject *parent=nullptr) | |
virtual | ~QFtp () |
qint64 | bytesAvailable () const |
int | cd (const QString &dir) |
void | clearPendingCommands () |
int | close () |
int | connectToHost (const QString &host, quint16 port=21) |
Command | currentCommand () const |
QIODevice * | currentDevice () const |
int | currentId () const |
Error | error () const |
QString | errorString () const |
int | get (const QString &file, QIODevice *dev=nullptr, TransferType type=Binary) |
bool | hasPendingCommands () const |
int | list (const QString &dir=QString ()) |
int | login (const QString &user=QString (), const QString &password=QString ()) |
int | mkdir (const QString &dir) |
int | put (const QByteArray &data, const QString &file, TransferType type=Binary) |
int | put (QIODevice *dev, const QString &file, TransferType type=Binary) |
int | rawCommand (const QString &command) |
qint64 | read (char *data, qint64 maxlen) |
QByteArray | readAll () |
int | remove (const QString &file) |
int | rename (const QString &oldname, const QString &newname) |
int | rmdir (const QString &dir) |
int | setProxy (const QString &host, quint16 port) |
int | setTransferMode (TransferMode mode) |
State | state () const |
Public Methods inherited from QObject | |
QObject (QObject *parent=nullptr) | |
~QObject () | |
bool | blockSignals (bool block) |
const QList< QObject * > & | children () const |
bool | connect (const QObject *sender, const QString &signalMethod, const QString &location, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection) |
bool | connect (const QObject *sender, const QString &signalMethod, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection) |
bool | disconnect (const QObject *receiver, const QString &slotMethod=QString ()) const |
bool | disconnect (const QString &signalMethod, const QString &location, const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const |
bool | disconnect (const QString &signalMethod=QString (), const QObject *receiver=nullptr, const QString &slotMethod=QString ()) const |
void | dumpObjectInfo () |
void | dumpObjectTree () |
QList< QString > | dynamicPropertyNames () const |
virtual bool | event (QEvent *event) |
virtual bool | eventFilter (QObject *watched, QEvent *event) |
template<typename T > | |
T | findChild (const QString &childName=QString ()) const |
template<class T > | |
QList< T > | findChildren (const QRegularExpression ®Exp, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const |
template<class T > | |
QList< T > | findChildren (const QString &childName=QString (), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const |
bool | inherits (const QString &className) const |
void | installEventFilter (QObject *filterObj) |
bool | isWidgetType () const |
bool | isWindowType () const |
void | killTimer (int id) |
const QMetaObject * | metaObject () const |
void | moveToThread (QThread *targetThread) |
QString | objectName () const |
QObject * | parent () const |
template<class T = QVariant> | |
T | property (const QString &name) const |
void | removeEventFilter (QObject *obj) |
void | setObjectName (const QString &name) |
void | setParent (QObject *parent) |
bool | setProperty (const QString &name, const QVariant &value) |
bool | signalsBlocked () const |
int | startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer) |
QThread * | thread () const |
Additional Inherited Members | |
Static Public Methods inherited from QObject | |
static bool | connect (const QObject *sender, const QMetaMethod &signalMethod, const QObject *receiver, const QMetaMethod &slotMethod, Qt::ConnectionType type=Qt::AutoConnection) |
static bool | connect (const QObject *sender, const QString &signalMethod, const QObject *receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection, const QString &location=QString ()) |
static bool | connect (const QObject *sender, const QString &signalMethod, const QString &location, const QObject *receiver, const QString &slotMethod, Qt::ConnectionType type=Qt::AutoConnection) |
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn > | |
static bool | connect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, SlotReturn (SlotClass::*slotMethod)(SlotArgs...), Qt::ConnectionType type=Qt::AutoConnection) |
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T > | |
static bool | connect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, T slotLambda, Qt::ConnectionType type=Qt::AutoConnection) |
static bool | disconnect (const QObject *sender, const QMetaMethod &signalMethod, const QObject *receiver, const QMetaMethod &slotMethod) |
static bool | disconnect (const QObject *sender, const QString &signalMethod, const QObject *receiver, const QString &slotMethod) |
static bool | disconnect (const QObject *sender, const QString &signalMethod, const QString &location, const QObject *receiver, const QString &slotMethod) |
static bool | disconnect (const QObject *sender, std::nullptr_t, const QObject *receiver, std::nullptr_t) |
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class SlotClass , class... SlotArgs, class SlotReturn > | |
static bool | disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, SlotReturn (SlotClass::*slotMethod)(SlotArgs...)) |
template<class Sender , class SignalClass , class... SignalArgs, class Receiver > | |
static bool | disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, std::nullptr_t slotMethod=nullptr) |
template<class Sender , class SignalClass , class... SignalArgs, class Receiver , class T > | |
static bool | disconnect (const Sender *sender, void (SignalClass::*signalMethod)(SignalArgs...), const Receiver *receiver, T slotMethod) |
static QMetaObject & | staticMetaObject () |
static QString | tr (const char *text, const char *comment=nullptr, std::optional< int > numArg=std::optional< int >()) |
Protected Methods inherited from QObject | |
virtual void | childEvent (QChildEvent *event) |
virtual void | connectNotify (const QMetaMethod &signalMethod) const |
virtual void | customEvent (QEvent *event) |
virtual void | disconnectNotify (const QMetaMethod &signalMethod) const |
bool | isSignalConnected (const QMetaMethod &signalMethod) const |
int | receivers (const QString &signal) const |
QObject * | sender () const |
int | senderSignalIndex () const |
virtual void | timerEvent (QTimerEvent *event) |
Properties inherited from QObject | |
objectName | |
Related Functions inherited from QObject | |
T | qobject_cast (QObject *object) |
QObjectList | |
The QFtp class provides an implementation of the client side of FTP protocol.
This class provides a direct interface to FTP that allows you to have more control over the requests. However, for new applications, it is recommended to use QNetworkAccessManager and QNetworkReply, as those classes possess a simpler, yet more powerful API.
The class works asynchronously, so there are no blocking functions. If an operation can not be executed immediately, the method will still return straight away and the operation will be scheduled for later execution. The results of scheduled operations are reported via signals. This approach depends on the event loop being in operation.
The operations that can be scheduled (they are called "commands" in the rest of the documentation) are the following: connectToHost(), login(), close(), list(), cd(), get(), put(), remove(), mkdir(), rmdir(), rename() and rawCommand().
All of these commands return a unique identifier that allows you to keep track of the command that is currently being executed. When the execution of a command starts, the commandStarted() signal with the command's identifier is emitted. When the command is finished, the commandFinished() signal is emitted with the command's identifier and a bool that indicates whether the command finished with an error.
In some cases you might want to execute a sequence of commands to connect and login to a FTP server.
In this case two FTP commands have been scheduled. When the last scheduled command has finished, a done() signal is emitted with a bool argument that tells you whether the sequence finished with an error. If an error occurs during the execution of one of the commands in a sequence of commands, all the pending commands are cleared and no signals are emitted for them. Some commands like list(), emit additional signals to report their results.
The following is an example of how to download the ReadMe.txt file from an FTP server.
For this example the following sequence of signals is emitted (with small variations, depending on network traffic, etc.):
The dataTransferProgress() signal in the above example is useful if you want to show a progress bar to inform the user about the progress of the download. The readyRead() signal tells you that there is data ready to be read. The amount of data can be queried then with the bytesAvailable() method and retrieved by calling read() or readAll().
If the login fails for the above example, the following signals will be emitted.
You can then get details about the error with the error() and errorString() functions.
For file transfer, QFtp can use both active or passive mode, and it uses passive file transfer mode by default; see the documentation for setTransferMode() for more details about this.
Call setProxy() to make QFtp connect via an FTP proxy server.
The functions currentId() and currentCommand() provide more information about the currently executing command.
The functions hasPendingCommands() and clearPendingCommands() allow you to query and clear the list of pending commands.
If you are an experienced network programmer and want to have complete control you can use rawCommand() to execute arbitrary FTP commands.
enum QFtp::Command |
This enum is used as the return value for the currentCommand() method. This allows you to perform specific actions for particular commands, e.g. in a FTP client, you might want to clear the directory view when a list() command is started; in this case you can simply check in the slot connected to the start() signal if the currentCommand() is List
.
Constant | Value | Description |
---|---|---|
QFtp::None | 0 | No command is being executed. |
QFtp::SetTransferMode | 1 | set the transfer mode. |
QFtp::SetProxy | 2 | switch proxying on or off. |
QFtp::ConnectToHost | 3 | connectToHost() is being executed. |
QFtp::Login | 4 | login() is being executed. |
QFtp::Close | 5 | close() is being executed. |
QFtp::List | 6 | list() is being executed. |
QFtp::Cd | 7 | cd() is being executed. |
QFtp::Get | 8 | get() is being executed. |
QFtp::Put | 9 | put() is being executed. |
QFtp::Remove | 10 | remove() is being executed. |
QFtp::Mkdir | 11 | mkdir() is being executed. |
QFtp::Rmdir | 12 | rmdir() is being executed. |
QFtp::Rename | 13 | rename() is being executed. |
QFtp::RawCommand | 14 | rawCommand() is being executed. |
enum QFtp::Error |
This enum identifies the error that occurred.
Constant | Value | Description |
---|---|---|
QFtp::NoError | 0 | No error occurred. |
QFtp::HostNotFound | 2 | The host name lookup failed. |
QFtp::ConnectionRefused | 3 | The server refused the connection. |
QFtp::NotConnected | 4 | Tried to send a command, but there is no connection to a server. |
QFtp::UnknownError | 1 | An error other than those specified above occurred. |
enum QFtp::State |
This enum defines the connection state:
Constant | Value | Description |
---|---|---|
QFtp::Unconnected | 0 | There is no connection to the host. |
QFtp::HostLookup | 1 | A host name lookup is in progress. |
QFtp::Connecting | 2 | An attempt to connect to the host is in progress. |
QFtp::Connected | 3 | Connection to the host has been achieved. |
QFtp::LoggedIn | 4 | Connection and user login have been achieved. |
QFtp::Closing | 5 | The connection is closing down, but it is not yet closed. (The state will be Unconnected when the connection is closed.) |
enum QFtp::TransferMode |
FTP works with two socket connections; one for commands and another for transmitting data. While the command connection is always initiated by the client, the second connection can be initiated by either the client or the server.
This enum defines whether the client (Passive mode) or the server (Active mode) should set up the data connection.
Constant | Value | Description |
---|---|---|
QFtp::Passive | 1 | The client connects to the server to transmit its data. |
QFtp::Active | 0 | The server connects to the client to transmit its data. |
enum QFtp::TransferType |
This enum identifies the data transfer type used with get and put commands.
Constant | Value | Description |
---|---|---|
QFtp::Binary | 0 | The data will be transferred in Binary mode. |
QFtp::Ascii | 1 | The data will be transferred in Ascii mode and new line characters will be converted to the local format. |
|
explicit |
Constructs a QFtp object with the given parent.
|
virtual |
Destructor.
|
slot |
Aborts the current command and deletes all scheduled commands.
If there is an unfinished command (i.e. a command for which the commandStarted() signal has been emitted, but for which the commandFinished() signal has not been emitted), this method sends an ABORT
command to the server. When the server replies that the command is aborted, the commandFinished() signal with the error
argument set to true
is emitted for the command. Due to timing issues, it is possible that the command had already finished before the abort request reached the server, in which case, the commandFinished() signal is emitted with the error
argument set to false
.
For all other commands that are affected by the abort(), no signals are emitted.
If you do not start further FTP commands directly after the abort(), there will not be any scheduled commands and the done() signal is emitted.
false
, even though the command did not complete successfully.qint64 QFtp::bytesAvailable | ( | ) | const |
Returns the number of bytes that can be read from the data socket at the moment.
int QFtp::cd | ( | const QString & | dir | ) |
Changes the working directory of the server to dir.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished().
When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
void QFtp::clearPendingCommands | ( | ) |
Deletes all pending commands from the list of scheduled commands. This does not affect the command that is being executed. If you want to stop this as well, use abort().
int QFtp::close | ( | ) |
Closes the connection to the FTP server.
The stateChanged() signal is emitted when the state of the connecting process changes, e.g. to Closing
, then Unconnected
.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished().
When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
|
signal |
This signal is emitted when processing the command identified by id has finished. If error is true if an error occurred during the processing, otherwise error is false.
|
signal |
This signal is emitted when processing the command identified by id starts.
Connects to the FTP server host using the specified port. The stateChanged() signal is emitted when the state of the connecting process changes. For example, from HostLookup
to Connecting
.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished(). When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
Command QFtp::currentCommand | ( | ) | const |
Returns the command type of the FTP command being executed or None
if there is no command being executed.
QIODevice * QFtp::currentDevice | ( | ) | const |
Returns the QIODevice pointer that is used by the FTP command to read data from or store data to. If there is no current FTP command being executed or if the command does not use an IO device, this method returns a nullptr. This method can be used to delete the QIODevice in the slot connected to the commandFinished() signal.
int QFtp::currentId | ( | ) | const |
Returns the identifier of the FTP command that is being executed or 0 if there is no command being executed.
This signal is emitted in response to a get() or put() request to indicate the current progress of the download or upload.
done is the amount of data that has already been transferred and total is the total amount of data to be read or written. It is possible that the QFtp class is not able to determine the total amount of data that should be transferred, in which case total is 0. (If you connect this signal to a QProgressBar, the progress bar shows a busy indicator if the total is 0).
|
signal |
This signal is emitted when the last pending command has finished; (it is emitted after the last command's commandFinished() signal). error is true if an error occurred during the processing, otherwise error is false.
Error QFtp::error | ( | ) | const |
Returns the last error that occurred. This is useful to find out what went wrong when receiving a commandFinished() or a done() signal with the error
argument set to true
. If you start a new command, the error status is reset to NoError
.
QString QFtp::errorString | ( | ) | const |
Returns a human readable description of the last error that occurred. This is useful for presenting an error message to the user when receiving a commandFinished() or a done() signal with the error
argument set to true
. The error string is often (but not always) the reply from the server, so it is not always possible to translate the string. If the message comes from CopperSpice, the string has already passed through tr().
int QFtp::get | ( | const QString & | file, |
QIODevice * | dev = nullptr , |
||
TransferType | type = Binary |
||
) |
Downloads the given file from the server. If dev is a nullptr then the readyRead() signal is emitted when there is data available to read. The data can be retrieved by calling read() or readAll(). If dev is a valid pointer the data will written directly to the given QIoDevice. This pointer must remain valid until the commandFinished() signal is emitted.
The data is transferred as Binary or Ascii depending on the value of type. This method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished(). When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
bool QFtp::hasPendingCommands | ( | ) | const |
Returns true if there are any commands scheduled that have not yet been executed, otherwise returns false. The command that is being executed is not considered as a scheduled command.
Lists the contents of directory dir on the FTP server. If dir is empty, it lists the contents of the current directory. The listInfo() signal is emitted for each directory entry found.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished().
When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
|
signal |
Logs in to the FTP server with the username of user and the given password. The stateChanged() signal is emitted when the state of the connecting process changes, for example to LoggedIn
.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished(). When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
int QFtp::mkdir | ( | const QString & | dir | ) |
Creates a directory called dir on the server.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished().
When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
int QFtp::put | ( | const QByteArray & | data, |
const QString & | file, | ||
TransferType | type = Binary |
||
) |
Writes a copy of the given data to the file called file on the server. The progress of the upload is reported by the dataTransferProgress() signal.
The data is transferred as Binary or Ascii depending on the value of type.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished().
When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
Since this method takes a copy of the data, you can discard your own copy when this method returns.
int QFtp::put | ( | QIODevice * | dev, |
const QString & | file, | ||
TransferType | type = Binary |
||
) |
Reads the data from the IO device dev, and writes it to the file called file on the server. The data is read in chunks from the IO device, so this overload allows you to transmit large amounts of data without the need to read all the data into memory at once.
The data is transferred as Binary or Ascii depending on the value of type.
Make sure that the dev pointer is valid for the duration of the operation (it is safe to delete it when the commandFinished() is emitted).
int QFtp::rawCommand | ( | const QString & | command | ) |
Sends the raw FTP command to the FTP server. This is useful for low-level FTP access. If the operation you wish to perform has an equivalent QFtp method, we recommend using the method instead of raw FTP commands since the functions are easier and safer. The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously.
The method returns a unique identifier which is passed by commandStarted() and commandFinished(). When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
|
signal |
This signal is emitted in response to the rawCommand() method. The given replyCode is the 3 digit reply code and detail is the text that follows the reply code.
Reads maxlen bytes from the data socket into data and returns the number of bytes read. Returns -1 if an error occurred.
QByteArray QFtp::readAll | ( | ) |
Reads all the bytes available from the data socket and returns them.
|
signal |
This signal is emitted in response to a get() command when there is new data to read. If you specify a device as the second argument in the get() command, this signal is not emitted; instead the data is written directly to the device. The data can be retrieved by calling read() or readAll(). This signal is useful if you want to process the data in chunks as soon as it becomes available. If you are only interested in the complete data, just connect to the commandFinished() signal and read the data then instead.
int QFtp::remove | ( | const QString & | file | ) |
Deletes the file called file from the server. The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished(). When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
Renames the file called oldname to newname on the server. The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished(). When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
int QFtp::rmdir | ( | const QString & | dir | ) |
Removes the directory called dir from the server.
The method does not block and returns immediately. The command is scheduled, and its execution is performed asynchronously. The method returns a unique identifier which is passed by commandStarted() and commandFinished().
When the command is started the commandStarted() signal is emitted. When it is finished the commandFinished() signal is emitted.
Enables use of the FTP proxy on host and port. Calling this method with an empty host value disables proxying. QFtp does not support FTP-over-HTTP proxy servers. Use QNetworkAccessManager for this.
int QFtp::setTransferMode | ( | TransferMode | mode | ) |
Sets the current FTP transfer mode to mode. The default is QFtp::Passive.
State QFtp::state | ( | ) | const |
Returns the current state of the object. When the state changes, the stateChanged() signal is emitted.
|
signal |
This signal is emitted when the state of the connection changes. The argument state is the new state of the connection; it is one of the State values. It is usually emitted in response to a connectToHost() or close() command, but it can also be emitted "spontaneously", e.g. when the server closes the connection unexpectedly.