class QNetworkProxy

The QNetworkProxy class provides a network layer proxy. More…

Synopsis

Methods

Static functions

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

QNetworkProxy provides the method for configuring network layer proxy support to the Qt network classes. The currently supported classes are QAbstractSocket , QTcpSocket , QUdpSocket , QTcpServer and QNetworkAccessManager . The proxy support is designed to be as transparent as possible. This means that existing network-enabled applications that you have written should automatically support network proxy using the following code.

proxy = QNetworkProxy()
proxy.setType(QNetworkProxy.Socks5Proxy)
proxy.setHostName("proxy.example.com")
proxy.setPort(1080)
proxy.setUser("username")
proxy.setPassword("password")
QNetworkProxy.setApplicationProxy(proxy)

An alternative to setting an application wide proxy is to specify the proxy for individual sockets using setProxy() and setProxy() . In this way, it is possible to disable the use of a proxy for specific sockets using the following code:

serverSocket.setProxy(QNetworkProxy.NoProxy)

Network proxy is not used if the address used in connectToHost() , bind() or listen() is equivalent to LocalHost or LocalHostIPv6 .

Each type of proxy support has certain restrictions associated with it. You should read the ProxyType documentation carefully before selecting a proxy type to use.

Note

Changes made to currently connected sockets do not take effect. If you need to change a connected socket, you should reconnect it.

SOCKS5

The SOCKS5 support since Qt 4 is based on RFC 1928 and RFC 1929 . The supported authentication methods are no authentication and username/password authentication. Both IPv4 and IPv6 are supported. Domain names are resolved through the SOCKS5 server if the HostNameLookupCapability is enabled, otherwise they are resolved locally and the IP address is sent to the server. There are several things to remember when using SOCKS5 with QUdpSocket and QTcpServer :

With QUdpSocket , a call to bind() may fail with a timeout error. If a port number other than 0 is passed to bind() , it is not guaranteed that it is the specified port that will be used. Use localPort() and localAddress() to get the actual address and port number in use. Because proxied UDP goes through two UDP connections, it is more likely that packets will be dropped.

With QTcpServer a call to listen() may fail with a timeout error. If a port number other than 0 is passed to listen() , then it is not guaranteed that it is the specified port that will be used. Use serverPort() and serverAddress() to get the actual address and port used to listen for connections. SOCKS5 only supports one accepted connection per call to listen() , and each call is likely to result in a different serverPort() being used.

class ProxyType

This enum describes the types of network proxying provided in Qt.

There are two types of proxies that Qt understands: transparent proxies and caching proxies. The first group consists of proxies that can handle any arbitrary data transfer, while the second can only handle specific requests. The caching proxies only make sense for the specific classes where they can be used.

Constant

Description

QNetworkProxy.NoProxy

No proxying is used

QNetworkProxy.DefaultProxy

Proxy is determined based on the application proxy set using setApplicationProxy()

QNetworkProxy.Socks5Proxy

Socks5 proxying is used

QNetworkProxy.HttpProxy

HTTP transparent proxying is used

QNetworkProxy.HttpCachingProxy

Proxying for HTTP requests only

QNetworkProxy.FtpCachingProxy

Proxying for FTP requests only

The table below lists different proxy types and their capabilities. Since each proxy type has different capabilities, it is important to understand them before choosing a proxy type.

Proxy type

Description

Default capabilities

SOCKS 5

Generic proxy for any kind of connection. Supports TCP, UDP, binding to a port (incoming connections) and authentication.

TunnelingCapability , ListeningCapability , UdpTunnelingCapability , HostNameLookupCapability

HTTP

Implemented using the “CONNECT” command, supports only outgoing TCP connections; supports authentication.

TunnelingCapability , CachingCapability , HostNameLookupCapability

Caching-only HTTP

Implemented using normal HTTP commands, it is useful only in the context of HTTP requests (see QNetworkAccessManager )

CachingCapability , HostNameLookupCapability

Caching FTP

Implemented using an FTP proxy, it is useful only in the context of FTP requests (see QNetworkAccessManager )

CachingCapability , HostNameLookupCapability

Also note that you shouldn’t set the application default proxy ( setApplicationProxy() ) to a proxy that doesn’t have the TunnelingCapability capability. If you do, QTcpSocket will not know how to open connections.

class Capability

(inherits enum.Flag) These flags indicate the capabilities that a given proxy server supports.

QNetworkProxy sets different capabilities by default when the object is created (see ProxyType for a list of the defaults). However, it is possible to change the capabilities after the object has been created with setCapabilities() .

The capabilities that QNetworkProxy supports are:

Constant

Description

QNetworkProxy.TunnelingCapability

Ability to open transparent, tunneled TCP connections to a remote host. The proxy server relays the transmission verbatim from one side to the other and does no caching.

QNetworkProxy.ListeningCapability

Ability to create a listening socket and wait for an incoming TCP connection from a remote host.

QNetworkProxy.UdpTunnelingCapability

Ability to relay UDP datagrams via the proxy server to and from a remote host.

QNetworkProxy.CachingCapability

Ability to cache the contents of the transfer. This capability is specific to each protocol and proxy type. For example, HTTP proxies can cache the contents of web data transferred with “GET” commands.

QNetworkProxy.HostNameLookupCapability

Ability to connect to perform the lookup on a remote host name and connect to it, as opposed to requiring the application to perform the name lookup and request connection to IP addresses only.

QNetworkProxy.SctpTunnelingCapability

Ability to open transparent, tunneled SCTP connections to a remote host.

QNetworkProxy.SctpListeningCapability

Ability to create a listening socket and wait for an incoming SCTP connection from a remote host.
__init__()

Constructs a QNetworkProxy with DefaultProxy type.

The proxy type is determined by applicationProxy() , which defaults to NoProxy or a system-wide proxy if one is configured.

__init__(other)
Parameters:

other – QNetworkProxy

Constructs a copy of other.

__init__(type[, hostName=""[, port=0[, user=""[, password=""]]]])
Parameters:

  • type – ProxyType

  • hostName – str

  • port – int

  • user – str

  • password – str

Constructs a QNetworkProxy with type, hostName, port, user and password.

The default capabilities for proxy type type are set automatically.

See also

capabilities()

static applicationProxy()
Return type:

QNetworkProxy

Returns the application level network proxying.

If a QAbstractSocket or QTcpSocket has the DefaultProxy type, then the QNetworkProxy returned by this function is used.

capabilities()
Return type:

Combination of Capability

Returns the capabilities of this proxy server.

hasRawHeader(headerName)
Parameters:

headerName – QByteArray

Return type:

bool

Returns true if the raw header headerName is in use for this proxy. Returns false if the proxy is not of type HttpProxy or HttpCachingProxy .

header(header)
Parameters:

header – KnownHeaders

Return type:

object

Returns the value of the known network header header if it is in use for this proxy. If it is not present, returns QVariant() (i.e., an invalid variant).

headers()
Return type:

QHttpHeaders

Returns headers that are set in this network request.

If the proxy is not of type HttpProxy or HttpCachingProxy , default constructed QHttpHeaders is returned.

See also

setHeaders()

hostName()
Return type:

str

Returns the host name of the proxy host.

isCachingProxy()
Return type:

bool

Returns true if this proxy supports the CachingCapability capability.

In Qt 4.4, the capability was tied to the proxy type, but since Qt 4.5 it is possible to remove the capability of caching from a proxy by calling setCapabilities() .

isTransparentProxy()
Return type:

bool

Returns true if this proxy supports transparent tunneling of TCP connections. This matches the TunnelingCapability capability.

In Qt 4.4, the capability was tied to the proxy type, but since Qt 4.5 it is possible to remove the capability of caching from a proxy by calling setCapabilities() .

__ne__(other)
Parameters:

other – QNetworkProxy

Return type:

bool

Compares the value of this network proxy to other and returns true if they differ.

__eq__(other)
Parameters:

other – QNetworkProxy

Return type:

bool

Compares the value of this network proxy to other and returns true if they are equal (same proxy type, server as well as username and password)

password()
Return type:

str

Returns the password used for authentication.

port()
Return type:

int

Returns the port of the proxy host.

rawHeader(headerName)
Parameters:

headerName – QByteArray

Return type:

QByteArray

Returns the raw form of header headerName. If no such header is present or the proxy is not of type HttpProxy or HttpCachingProxy , an empty QByteArray is returned, which may be indistinguishable from a header that is present but has no content (use hasRawHeader() to find out if the header exists or not).

Raw headers can be set with setRawHeader() or with setHeader() .

rawHeaderList()
Return type:

.list of QByteArray

Returns a list of all raw headers that are set in this network proxy. The list is in the order that the headers were set.

If the proxy is not of type HttpProxy or HttpCachingProxy an empty QList is returned.

static setApplicationProxy(proxy)
Parameters:

proxy – QNetworkProxy

Sets the application level network proxying to be networkProxy.

If a QAbstractSocket or QTcpSocket has the DefaultProxy type, then the QNetworkProxy set with this function is used. If you want more flexibility in determining which proxy is used, use the QNetworkProxyFactory class.

Setting a default proxy value with this function will override the application proxy factory set with setApplicationProxyFactory , and disable the use of a system proxy.

setCapabilities(capab)
Parameters:

capab – Combination of Capability

Sets the capabilities of this proxy to capabilities.

setHeader(header, value)
Parameters:

Sets the value of the known header header to be value, overriding any previously set headers. This operation also sets the equivalent raw HTTP header.

If the proxy is not of type HttpProxy or HttpCachingProxy this has no effect.

setHeaders(newHeaders)
Parameters:

newHeaders – QHttpHeaders

This is an overloaded function.

setHostName(hostName)
Parameters:

hostName – str

Sets the host name of the proxy host to be hostName.

setPassword(password)
Parameters:

password – str

Sets the password for proxy authentication to be password.

setPort(port)
Parameters:

port – int

Sets the port of the proxy host to be port.

setRawHeader(headerName, value)
Parameters:

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

Sets the header headerName to be of value headerValue. If headerName corresponds to a known header (see KnownHeaders ), the raw format will be parsed and the corresponding “cooked” header will be set as well.

For example:

request.setRawHeader(QByteArray("Last-Modified"), QByteArray("Sun, 06 Nov 1994 08:49:37 GMT"))

will also set the known header LastModifiedHeader to be the QDateTime object of the parsed date.

Note

Setting the same header twice overrides the previous setting. To accomplish the behaviour of multiple HTTP headers of the same name, you should concatenate the two values, separating them with a comma (“,”) and set one single raw header.

If the proxy is not of type HttpProxy or HttpCachingProxy this has no effect.

setType(type)
Parameters:

type – ProxyType

Sets the proxy type for this instance to be type.

Note that changing the type of a proxy does not change the set of capabilities this QNetworkProxy object holds if any capabilities have been set with setCapabilities() .

setUser(userName)
Parameters:

userName – str

Sets the user name for proxy authentication to be user.

swap(other)
Parameters:

other – QNetworkProxy

Swaps this network proxy instance with other. This function is very fast and never fails.

type()
Return type:

ProxyType

Returns the proxy type for this instance.

See also

setType()

user()
Return type:

str

Returns the user name used for authentication.