#include <DNSSD/ServiceBrowser>

Inheritance diagram for DNSSD::ServiceBrowser:

Public Types
enum	State { Working, Stopped, Unsupported }

Signals
void	finished ()

void	serviceAdded (DNSSD::RemoteService::Ptr service)

void	serviceRemoved (DNSSD::RemoteService::Ptr service)

Public Member Functions
	ServiceBrowser (const QString &type, bool autoResolve=false, const QString &domain=QString(), const QString &subtype=QString())

	~ServiceBrowser ()

bool	isAutoResolving () const

QList< RemoteService::Ptr >	services () const

virtual void	startBrowse ()

Static Public Member Functions
static QString	getLocalHostName ()

static State	isAvailable ()

static QHostAddress	resolveHostName (const QString &hostname)

Protected Member Functions
virtual void	virtual_hook (int, void *)

Detailed Description

Browses for network services advertised over DNS-SD.

Browses the service types being published on a domain.

This is the central class in the DNSSD library for applications that want to discover services on network.

Suppose that you need list of web servers running. Then you might do something like

DNSSD::ServiceBrowser* browser = new DNSSD::ServiceBrowser("_http._tcp");
connect(browser, SIGNAL(serviceAdded(RemoteService::Ptr)),
        this,    SLOT(addService(RemoteService::Ptr)));
connect(browser, SIGNAL(serviceRemoved(RemoteService::Ptr)),
        this,    SLOT(delService(RemoteService::Ptr)));
browser->startBrowse();

In above example addService() will be called for every web server already running and for every web service that subsequently appears on the network and delService() will be called when a server previously advertised is stopped.

Because no domain was passed to constructor, the default domain will be searched. To find other domains to browse for services on, use DomainBrowser.

Author: Jakub Stachowski

This class is mostly useful for generic utilities for browsing all the published services on a local network. Applications that wish to find out about available services of a particular type (such as web servers) should use ServiceBrowser.

ServiceTypeBrowser provides a list of all the service types published by at least one service on a given domain.

Author: Jakub Stachowski

Definition at line 64 of file servicebrowser.h.

Member Enumeration Documentation

enum DNSSD::ServiceBrowser::State

Availability of DNS-SD services.

Enumerator
Working	the service is available
Stopped	not available because mDnsd or Avahi daemon is not running
Unsupported	not available because KDE was compiled without DNS-SD support

Definition at line 72 of file servicebrowser.h.

Constructor & Destructor Documentation

DNSSD::ServiceBrowser::ServiceBrowser	(	const QString &	type,
		bool	autoResolve = `false`,
		const QString &	domain = `QString()`,
		const QString &	subtype = `QString()`
	)

explicit

Create a ServiceBrowser for a particular service type.

DomainBrowser can be used to find other domains to browse on. If no domain is given, the default domain is used.

The service type is the high-level protocol type, followed by a dot, followed by the transport protocol type (_tcp or _udp). The DNS-SD website maintains a full list of service types.

The subtype parameter allows you to do more fine-grained filtering on the services you are interested in. So you might request only FTP servers that allow anonymous access by passing "_ftp._tcp" as the type and "_anon" as the subtype. Subtypes are particularly important for types like _soap and _upnp, which are far too generic for most applications. In these cases, the subtype can be used to specify the particular SOAP or UPnP protocol they want.

Warning: Enabling autoResolve will increase network usage by resolving all services, so this feature should be used only when necessary.

Parameters

type	service types to browse for (example: "_http._tcp")
autoResolve	discovered services will be resolved before being reported with the serviceAdded() signal
domain	a domain to search on instead of the default one
subtype	only browse for a specific subtype

See also: startBrowse() and isAvailable()

Definition at line 29 of file dummy-servicebrowser.cpp.

DNSSD::ServiceBrowser::~ServiceBrowser ( )

Definition at line 42 of file dummy-servicebrowser.cpp.

Member Function Documentation

void DNSSD::ServiceBrowser::finished ( )

signal

Emitted when the list of published services has settled.

This signal is emitted once after startBrowse() is called when all the services of the requested type that are currently published have been reported (even if none are available or the DNS-SD service is not available). It is emitted again when a new batch of services become available or disappear.

For example, if a new host is connected to network and announces some services watched for by this ServiceBrowser, they will be reported by one or more serviceAdded() signals and the whole batch will be concluded by finished().

This signal can be used by applications that just want to get a list of the currently available services (similar to a directory listing) and do not care about adding or removing services that appear or disappear later.

Warning: There is no guarantee any RemoteService pointers received by serviceAdded() will be valid by the time this signal is emitted, so you should either do all your work involving them in the slot receiving the serviceAdded() signal, or you should listen to serviceRemoved() as well.

See also: serviceAdded() and serviceRemoved()

QString DNSSD::ServiceBrowser::getLocalHostName ( )

static

The mDNS hostname of the local machine.

Usually this will return the same as QHostInfo::localHostName(), but it may be changed to something different in the Avahi configuration file (if using the Avahi backend).

Returns: the hostname, or an empty string on failure

Since: 4.2

Definition at line 64 of file dummy-servicebrowser.cpp.

bool DNSSD::ServiceBrowser::isAutoResolving ( ) const

Whether discovered services are resolved before being reported.

Returns: the value of the autoResolve parameter passed to the constructor

Since: 4.1

Definition at line 32 of file dummy-servicebrowser.cpp.

ServiceBrowser::State DNSSD::ServiceBrowser::isAvailable ( )

static

Checks availability of DNS-SD services.

Although this method is part of ServiceBrowser, none of the classes in this library will be able to perform their intended function if this method does not return Working.

If this method does not return Working, it is still safe to call any of the methods in this library. However, no services will be found or published and no domains will be found.

If you use this function to report an error to the user, below is a suggestion on how to word the errors when publishing a service. The first line of each error message can also be used for reporting errors when browsing for services.

switch(DNSSD::ServiceBrowser::isAvailable()) {
case DNSSD::ServiceBrowser::Working:
    return "";
case DNSSD::ServiceBrowser::Stopped:
    return i18n("<p>The Zeroconf daemon is not running. See the Service"
                " Discovery Handbook for more information.<br/>"
                "Other users will not see the services provided by this
                " system when browsing the network via zeroconf, but "
                " normal access will still work.</p>");
case DNSSD::ServiceBrowser::Unsupported:
    return i18n("<p>Zeroconf support is not available in this version of KDE."
                " See the Service Discovery Handbook for more information.<br/>"
                "Other users will not see the services provided by this
                " application when browsing the network via zeroconf, but "
                " normal access will still work.</p>");
default:
    return i18n("<p>Unknown error with Zeroconf.<br/>"
                "Other users will not see the services provided by this
                " application when browsing the network via zeroconf, but "
                " normal access will still work.</p>");
}

Definition at line 38 of file dummy-servicebrowser.cpp.

QHostAddress DNSSD::ServiceBrowser::resolveHostName ( const QString & hostname )

static

Resolves an mDNS hostname into an IP address.

This function is very rarely useful, since a properly configured system is able to resolve an mDNS-based host name using the system resolver (ie: you can just pass the mDNS hostname to KIO or other library).

Parameters

hostname the hostname to be resolved

Returns: a QHostAddress containing the IP address, or QHostAddress() if resolution failed

Since: 4.2

Definition at line 59 of file dummy-servicebrowser.cpp.

void DNSSD::ServiceBrowser::serviceAdded ( DNSSD::RemoteService::Ptr service )

signal

Emitted when new service is discovered.

If isAutoResolving() returns true, this will not be emitted until the service has been resolved.

Parameters

service a RemoteService object describing the service

See also: serviceRemoved() and finished()

void DNSSD::ServiceBrowser::serviceRemoved ( DNSSD::RemoteService::Ptr service )

signal

Emitted when a service is no longer published over DNS-SD.

The RemoteService object is removed from the services() list and deleted immediately after this signal returns.

Warning: Do not use a delayed connection with this signal

Parameters

service a RemoteService object describing the service

See also: serviceAdded() and finished()

QList< RemoteService::Ptr > DNSSD::ServiceBrowser::services ( ) const

The currently known services of the specified type.

Returns: a list of RemoteService pointers

See also: serviceAdded() and serviceRemoved()

Definition at line 51 of file dummy-servicebrowser.cpp.

void DNSSD::ServiceBrowser::startBrowse ( )

virtual

Starts browsing for services.

Only the first call to this function will have any effect.

Browsing stops when the ServiceBrowser object is destroyed.

Warning: The serviceAdded() signal may be emitted before this function returns.

See also: serviceAdded(), serviceRemoved() and finished()

Definition at line 46 of file dummy-servicebrowser.cpp.

void DNSSD::ServiceBrowser::virtual_hook	(	int	,
		void *
	)

protectedvirtual

Definition at line 56 of file dummy-servicebrowser.cpp.

The documentation for this class was generated from the following files:

DNSSD

Public Types

Signals

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

DNSSD

kdelibs API Reference

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