The UaDiscovery class manages a UA Client side discovery functionality. More...

#include <uadiscovery.h>

Public Member Functions
	UaDiscovery ()
	Creates a UaDiscovery client object.

	~UaDiscovery ()
	Destroys the UaDiscovery object.

UaStatus	findServers (const UaString &sDiscoveryURL, UaApplicationDescriptions &applicationDescriptions)
	Get a list of servers known by the discovery server. More...

UaStatus	findServers (ServiceSettings &serviceSettings, const UaString &sDiscoveryURL, ClientSecurityInfo &clientSecurityInfo, UaApplicationDescriptions &applicationDescriptions)
	Get a list of servers known by the discovery server. More...

UaStatus	findServers (ServiceSettings &serviceSettings, const UaString &sDiscoveryURL, ClientSecurityInfo &clientSecurityInfo, const UaStringArray &localIds, const UaStringArray &serverUris, UaApplicationDescriptions &applicationDescriptions)
	Gets a list of servers known by the discovery server. More...

UaStatus	getEndpoints (const UaString &sDiscoveryURL, UaEndpointDescriptions &endpointDescriptions)
	Gets a list of endpoints supported by the server. More...

UaStatus	getEndpoints (ServiceSettings &serviceSettings, const UaString &sDiscoveryURL, ClientSecurityInfo &clientSecurityInfo, UaEndpointDescriptions &endpointDescriptions)
	Gets a list of endpoints supported by the server. More...

UaStatus	getEndpoints (ServiceSettings &serviceSettings, const UaString &sDiscoveryURL, ClientSecurityInfo &clientSecurityInfo, const UaStringArray &localIds, const UaStringArray &transportProfileUris, UaEndpointDescriptions &endpointDescriptions)
	Gets a list of endpoints supported by the server. More...

UaStatus	findServersOnNetwork (ServiceSettings &serviceSettings, const UaString &sDiscoveryURL, ClientSecurityInfo &clientSecurityInfo, OpcUa_UInt32 startingRecordId, const UaStringArray &serverCapabilities, OpcUa_UInt32 maxRecordsToReturn, UaDateTime &lastCounterResetTime, UaServerOnNetworks &servers)
	Gets a list of discovery URLs of servers known in the cache of the discovery server. More...

UaStatus	findServersOnNetwork (ServiceSettings &serviceSettings, const UaString &sDiscoveryURL, ClientSecurityInfo &clientSecurityInfo, OpcUa_UInt32 startingRecordId, UaDateTime &lastCounterResetTime, UaServerOnNetworks &servers)
	Gets a list of discovery URLs of servers known in the cache of the discovery server. More...

UaStatus	queryDirectory (ServiceSettings &serviceSettings, const UaString &sGdsURL, OpcUa_UInt32 startingRecordId, UaDateTime &lastCounterResetTime, UaServerOnNetworks &servers)
	Get a list of servers known by the Directory in a global discovery server. More...

UaStatus	queryDirectory (ServiceSettings &serviceSettings, UaSession *pSession, OpcUa_UInt32 startingRecordId, UaDateTime &lastCounterResetTime, UaServerOnNetworks &servers)
	Get a list of servers known by the Directory in a global discovery server. More...

UaStatus	queryDirectory (ServiceSettings &serviceSettings, UaSession *pSession, OpcUa_UInt32 startingRecordId, OpcUa_UInt32 maxRecordsToReturn, const UaString &applicationName, const UaString &applicationUri, const UaString &productUri, const UaStringArray &serverCapabilities, UaDateTime &lastCounterResetTime, UaServerOnNetworks &servers)
	Get a filtered list of servers known by the Directory in a global discovery server. More...

UaStatus	queryDirectory (ServiceSettings &serviceSettings, const UaString &sGdsURL, SessionConnectInfo &sessionConnectInfo, SessionSecurityInfo &sessionSecurityInfo, OpcUa_UInt32 startingRecordId, OpcUa_UInt32 maxRecordsToReturn, const UaString &applicationName, const UaString &applicationUri, const UaString &productUri, const UaStringArray &serverCapabilities, UaDateTime &lastCounterResetTime, UaServerOnNetworks &servers)
	Get a filtered list of servers known by the Directory in a global discovery server. More...

Detailed Description

The UaDiscovery class manages a UA Client side discovery functionality.

Discovery is a two-step approach. In the first step, the available servers are discovered and in the second step the selected server is asked for its available Endpoints, describing combinations of protocols and security settings available to connect to the server.

Member Function Documentation

UaStatus UaClientSdk::UaDiscovery::findServers	(	const UaString &	sDiscoveryURL,
		UaApplicationDescriptions &	applicationDescriptions
	)

Get a list of servers known by the discovery server.

The discovery server is typically a Local Discovery Server (LDS) running on a host with OPC UA servers. It returns the servers available on this host.

The DiscoveryUrls contained in the returned ApplicationDescriptions can be used to call getEndpoints for the server of interest to get all information necessary to connect to this server.

Parameters

[in]	sDiscoveryURL	The URL identifying an OPC UA Discovery Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[out]	applicationDescriptions	Array of OpcUa_ApplicationDescription with the following information. ApplicationUri: The globally unique identifier for the application instance. ProductUri: The globally unique identifier for the product. ApplicationName: A localized descriptive name for the application. ApplicationType: The type of application. Possible values are SERVER, CLIENT, CLIENTANDSERVER, and DISCOVERYSERVER. DiscoveryUrls: A list of URLs for the discovery Endpoints provided by the application. Empty for type CLIENT.

UaStatus UaClientSdk::UaDiscovery::findServers	(	ServiceSettings &	serviceSettings,
		const UaString &	sDiscoveryURL,
		ClientSecurityInfo &	clientSecurityInfo,
		UaApplicationDescriptions &	applicationDescriptions
	)

Get a list of servers known by the discovery server.

The discovery server is typically a Local Discovery Server (LDS) running on a host with OPC UA servers. It returns the servers available on this host.

The DiscoveryUrls contained in the returned ApplicationDescriptions can be used to call getEndpoints for the server of interest to get all information necessary to connect to this server.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sDiscoveryURL	The URL identifying an OPC UA Discovery Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	clientSecurityInfo	The client defined security settings. See ClientSecurityInfo for more information.
[out]	applicationDescriptions	Array of OpcUa_ApplicationDescription with the following information. ApplicationUri: The globally unique identifier for the application instance. ProductUri: The globally unique identifier for the product. ApplicationName: A localized descriptive name for the application. ApplicationType: The type of application. Possible values are SERVER, CLIENT, CLIENTANDSERVER, and DISCOVERYSERVER. DiscoveryUrls: A list of URLs for the discovery Endpoints provided by the application. Empty for type CLIENT.

UaStatus UaClientSdk::UaDiscovery::findServers	(	ServiceSettings &	serviceSettings,
		const UaString &	sDiscoveryURL,
		ClientSecurityInfo &	clientSecurityInfo,
		const UaStringArray &	localIds,
		const UaStringArray &	serverUris,
		UaApplicationDescriptions &	applicationDescriptions
	)

Gets a list of servers known by the discovery server.

The discovery server is typically a Local Discovery Server (LDS) running on a host with OPC UA servers. It returns the servers available on this host.

The DiscoveryUrls contained in the returned ApplicationDescriptions can be used to call getEndpoints for the server of interest to get all information necessary to connect to this server.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sDiscoveryURL	The URL identifying an OPC UA Discovery Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	clientSecurityInfo	The client defined security settings. See ClientSecurityInfo for more information.
[in]	localIds	List of locales to use. The server should return the ServerName using one of locales specified. If the server supports more than one of the requested locales, then the server will use the locale that appears first in this list. If the server does not support any of the requested locales, it chooses an appropriate default locale. The server chooses an appropriate default locale if this list is empty.
[in]	serverUris	List of servers to return. All known servers are returned if the list is empty.
[out]	applicationDescriptions	Array of OpcUa_ApplicationDescription with the following information ApplicationUri: The globally unique identifier for the application instance. ProductUri: The globally unique identifier for the product. ApplicationName: A localized descriptive name for the application. ApplicationType: The type of application. Possible values are SERVER, CLIENT, CLIENTANDSERVER and DISCOVERYSERVER. DiscoveryUrls: A list of URLs for the discovery Endpoints provided by the application. Empty for type CLIENT.

UaStatus UaClientSdk::UaDiscovery::findServersOnNetwork	(	ServiceSettings &	serviceSettings,
		const UaString &	sDiscoveryURL,
		ClientSecurityInfo &	clientSecurityInfo,
		OpcUa_UInt32	startingRecordId,
		const UaStringArray &	serverCapabilities,
		OpcUa_UInt32	maxRecordsToReturn,
		UaDateTime &	lastCounterResetTime,
		UaServerOnNetworks &	servers
	)

Gets a list of discovery URLs of servers known in the cache of the discovery server.

The discovery server is typically a Local Discovery Server with multicast extension (LDS-ME) running on a host with OPC UA servers. It returns the servers in the mDNS cache of the LDS-ME. This cache is created from the servers announcing themselves through mDNS multicast messages in the local network.

The DiscoveryUrls contained in the returned ServerOnNetworks can be used to call getEndpoints for the server of interest to get all information necessary to connect to this server.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sDiscoveryURL	The URL identifying an OPC UA Discovery Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	clientSecurityInfo	The client defined security settings. See ClientSecurityInfo for more information.
[in]	startingRecordId	Only records with an identifier greater than this number will be returned. Specify 0 to start with the first record in the database.
[in]	serverCapabilities	The Servers returned shall support all of the server capabilities specified. If no server capabilities are provided this filter is not used.
[in]	maxRecordsToReturn	The maximum number of records to return in the response. 0 indicates that there is no limit.
[out]	lastCounterResetTime	The last time the counters were reset.
[out]	servers	A list of Servers which meet the filter criteria. The ServerOnNetwork structure contains the following information: RecordId: A unique identifier for the record. This can be used to fetch the next batch of servers in a subsequent call. ServerName: The name of the Server. This is typically the ApplicationName for the Server. DiscoveryUrl: The URL of the discovery Endpoint. ServerCapabilities: The list of server capabilities supported by the Server.

UaStatus UaClientSdk::UaDiscovery::findServersOnNetwork	(	ServiceSettings &	serviceSettings,
		const UaString &	sDiscoveryURL,
		ClientSecurityInfo &	clientSecurityInfo,
		OpcUa_UInt32	startingRecordId,
		UaDateTime &	lastCounterResetTime,
		UaServerOnNetworks &	servers
	)

Gets a list of discovery URLs of servers known in the cache of the discovery server.

The discovery server is typically a Local Discovery Server with multicast extension (LDS-ME) running on a host with OPC UA servers. It returns the servers in the mDNS cache of the LDS-ME. This cache is created from the servers announcing themselves through mDNS multicast messages in the local network.

The DiscoveryUrls contained in the returned ServerOnNetworks can be used to call getEndpoints for the server of interest to get all information necessary to connect to this server.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sDiscoveryURL	The URL identifying an OPC UA Discovery Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	clientSecurityInfo	The client defined security settings. See ClientSecurityInfo for more information.
[in]	startingRecordId	Only records with an identifier greater than this number will be returned. Specify 0 to start with the first record in the database.
[out]	lastCounterResetTime	The last time the counters were reset.
[out]	servers	A list of Servers which meet the filter criteria. The ServerOnNetwork structure contains the following information: RecordId: A unique identifier for the record. This can be used to fetch the next batch of servers in a subsequent call. ServerName: The name of the Server. This is typically the ApplicationName for the Server. DiscoveryUrl: The URL of the discovery Endpoint. ServerCapabilities: The list of server capabilities supported by the Server.

UaStatus UaClientSdk::UaDiscovery::getEndpoints	(	const UaString &	sDiscoveryURL,
		UaEndpointDescriptions &	endpointDescriptions
	)

Gets a list of endpoints supported by the server.

The discovery URL used to connect to the server and to get the endpoints is typically returned from findServers or other discovery methods like findServersOnNetwork or queryDirectory.

The EndpointDescriptions returned from the server provide all information like EnpointUrl, security settings and types of user authentication necessary to connect to the server.

Parameters

[in]	sDiscoveryURL	The discovery URL of an OPC UA Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[out]	endpointDescriptions	Array of OpcUa_EndpointDescription with the following information EndpointUrl: The URL used to connect to this Endpoint. ServerCertificate: The application instance certificate issued to the Server. SecurityMode: The type of security to apply to the messages. Possible values are None, Sign, and SignAndEncrypt. SecurityPolicyUri: The URI for SecurityPolicy to use when securing messages. See ClientSecurityInfo::sSecurityPolicy for more details. UserIdentityTokens: The user identity tokens that the Server will accept. TransportProfileUri: The URI of the Transport Profile supported by the Endpoint. SecurityLevel: A numeric value that indicates how secure the EndpointDescription is compared to other EndpointDescriptions for the same Server. A higher value indicates better security.

UaStatus UaClientSdk::UaDiscovery::getEndpoints	(	ServiceSettings &	serviceSettings,
		const UaString &	sDiscoveryURL,
		ClientSecurityInfo &	clientSecurityInfo,
		UaEndpointDescriptions &	endpointDescriptions
	)

Gets a list of endpoints supported by the server.

The discovery URL used to connect to the server and to get the endpoints is typically returned from findServers or other discovery methods like findServersOnNetwork or queryDirectory.

The EndpointDescriptions returned from the server provide all information like EnpointUrl, security settings and types of user authentication necessary to connect to the server.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sDiscoveryURL	The discovery URL of an OPC UA Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	clientSecurityInfo	The client defined security settings. See ClientSecurityInfo for more info.
[out]	endpointDescriptions	Array of OpcUa_EndpointDescription with the following information EndpointUrl: The URL used to connect to this Endpoint. ServerCertificate: The application instance certificate issued to the Server. SecurityMode: The type of security to apply to the messages. Possible values are None, Sign, and SignAndEncrypt. SecurityPolicyUri: The URI for SecurityPolicy to use when securing messages. See ClientSecurityInfo::sSecurityPolicy for more details. UserIdentityTokens: The user identity tokens that the Server will accept. TransportProfileUri: The URI of the Transport Profile supported by the Endpoint. SecurityLevel: A numeric value that indicates how secure the EndpointDescription is compared to other EndpointDescriptions for the same Server. A higher value indicates better security.

UaStatus UaClientSdk::UaDiscovery::getEndpoints	(	ServiceSettings &	serviceSettings,
		const UaString &	sDiscoveryURL,
		ClientSecurityInfo &	clientSecurityInfo,
		const UaStringArray &	localIds,
		const UaStringArray &	transportProfileUris,
		UaEndpointDescriptions &	endpointDescriptions
	)

Gets a list of endpoints supported by the server.

The discovery URL used to connect to the server and to get the endpoints is typically returned from findServers or other discovery methods like findServersOnNetwork or queryServersOnDirectory.

The EndpointDescriptions returned from the server provide all information like EnpointUrl, security settings and types of user authentication necessary to connect to the server.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sDiscoveryURL	The discovery URL of an OPC UA Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	clientSecurityInfo	The client defined security settings. See ClientSecurityInfo for more info.
[in]	localIds	List of locales to use. Specifies the locale to use when returning human readable strings.
[in]	transportProfileUris	List of Transport Profile that the returned Endpoints shall support. All Endpoints are returned if the list is empty. The transport profile URIs are defined as part of the OPC UA profiles. A complete list can be found at http://opcfoundation.org/profilereporting/ in the Transport Category. Commonly used profiles are http://opcfoundation.org/UA-Profile/Transport/uatcp-uasc-uabinary (mandatory) http://opcfoundation.org/UA-Profile/Transport/https-uabinary
[out]	endpointDescriptions	Array of OpcUa_EndpointDescription with the following information EndpointUrl: The URL used to connect to this Endpoint. ServerCertificate: The application instance certificate issued to the Server. SecurityMode: The type of security to apply to the messages. Possible values are None, Sign, and SignAndEncrypt. SecurityPolicyUri: The URI for SecurityPolicy to use when securing messages. See ClientSecurityInfo::sSecurityPolicy for more details. UserIdentityTokens: The user identity tokens that the Server will accept. TransportProfileUri: The URI of the Transport Profile supported by the Endpoint. SecurityLevel: A numeric value that indicates how secure the EndpointDescription is compared to other EndpointDescriptions for the same Server. A higher value indicates better security.

UaStatus UaClientSdk::UaDiscovery::queryDirectory	(	ServiceSettings &	serviceSettings,
		const UaString &	sGdsURL,
		OpcUa_UInt32	startingRecordId,
		UaDateTime &	lastCounterResetTime,
		UaServerOnNetworks &	servers
	)

Get a list of servers known by the Directory in a global discovery server.

Used to access the method QueryServers of the Directory object in a Global Discovery Server (GDS). The method is defined by the DirectoryType in the GDS information model.

The URL used to connected to the GDS must be passed in. Any Client is able to call the method on the GDS, however, the set of results returned may be restricted based on the Client’s user credentials. One of the overloads taking a UaSession or full security configuration must be used if user credentials are necessary.

It may be necessary to call this method several times to get all results from the GDS. The behaviour can be controlled with the parameters startingRecordId and maxRecordsToReturn. The ServerOnNetwork structure returned in the parameter servers contains the RecordId of the returned server. It can be used to calculate the startingRecordId for the next call to queryDirectory. If the returned value in lastCounterResetTime is after the first call to queryDirectory, it may make sense to start over from beginning since the list of registered servers was changed. The startingRecordId for the first call is 0.

This overload function does not apply any filters.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sGdsURL	The URL identifying an OPC UA GDS Directory Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in]	startingRecordId	Only records with an identifier greater than this number will be returned. Specify 0 to start with the first record in the database.
[out]	lastCounterResetTime	The last time the counters were reset.
[out]	servers	A list of Servers which meet the filter criteria. The ServerOnNetwork structure contains the following information: RecordId: A unique identifier for the record. This can be used to fetch the next batch of servers in a subsequent call. ServerName: The name of the Server. This is typically the ApplicationName for the Server. DiscoveryUrl: The URL of the discovery Endpoint. ServerCapabilities: The list of server capabilities supported by the Server.

UaStatus UaClientSdk::UaDiscovery::queryDirectory	(	ServiceSettings &	serviceSettings,
		UaSession *	pSession,
		OpcUa_UInt32	startingRecordId,
		UaDateTime &	lastCounterResetTime,
		UaServerOnNetworks &	servers
	)

Get a list of servers known by the Directory in a global discovery server.

Used to access the method QueryServers of the Directory object in a Global Discovery Server (GDS). The method is defined by the DirectoryType in the GDS information model.

A UaSession connected to the GDS must be passed in. Any Client is able to call the method on the GDS, however, the set of results returned may be restricted based on the Client’s user credentials. Therefore it may be required to configure the UaSession object with the right user token.

It may be necessary to call this method several times to get all results from the GDS. The behaviour can be controlled with the parameters startingRecordId and maxRecordsToReturn. The ServerOnNetwork structure returned in the parameter servers contains the RecordId of the returned server. It can be used to calculate the startingRecordId for the next call to queryDirectory. If the returned value in lastCounterResetTime is after the first call to queryDirectory, it may make sense to start over from beginning since the list of registered servers was changed. The startingRecordId for the first call is 0.

This overload function does not apply any filters.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	pSession	Session object used to call the QueryServers method on the GDS. The session must be connected.
[in]	startingRecordId	Only records with an identifier greater than this number will be returned. Specify 0 to start with the first record in the database.
[out]	lastCounterResetTime	The last time the counters were reset.
[out]	servers	A list of Servers which meet the filter criteria. The ServerOnNetwork structure contains the following information: RecordId: A unique identifier for the record. This can be used to fetch the next batch of servers in a subsequent call. ServerName: The name of the Server. This is typically the ApplicationName for the Server. DiscoveryUrl: The URL of the discovery Endpoint. ServerCapabilities: The list of server capabilities supported by the Server.

UaStatus UaClientSdk::UaDiscovery::queryDirectory	(	ServiceSettings &	serviceSettings,
		UaSession *	pSession,
		OpcUa_UInt32	startingRecordId,
		OpcUa_UInt32	maxRecordsToReturn,
		const UaString &	applicationName,
		const UaString &	applicationUri,
		const UaString &	productUri,
		const UaStringArray &	serverCapabilities,
		UaDateTime &	lastCounterResetTime,
		UaServerOnNetworks &	servers
	)

Get a filtered list of servers known by the Directory in a global discovery server.

Used to access the method QueryServers of the Directory object in a Global Discovery Server (GDS). The method is defined by the DirectoryType in the GDS information model.

A UaSession connected to the GDS must be passed in. Any Client is able to call the method on the GDS, however, the set of results returned may be restricted based on the Client’s user credentials. Therefore it may be required to configure the UaSession object with the right user token.

It may be necessary to call this method several times to get all results from the GDS. The behaviour can be controlled with the parameters startingRecordId and maxRecordsToReturn. The ServerOnNetwork structure returned in the parameter servers contains the RecordId of the returned server. It can be used to calculate the startingRecordId for the next call to queryDirectory. If the returned value in lastCounterResetTime is after the first call to queryDirectory, it may make sense to start over from beginning since the list of registered servers was changed. The startingRecordId for the first call is 0.

The results can be filtered with the parameters applicationName, applicationUri, productUri and serverCapabilities. Filters are combined in an AND operation. The serverCapabilities parameter is an array and a Server will pass this filter if it supports all of the specified capabilities. The other filter parameters are strings where the syntax of the LIKE FilterOperator can be used. See UaString::like() for more details.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	pSession	Session object used to call the QueryServers method on the GDS. The session must be connected.
[in]	startingRecordId	Only records with an identifier greater than this number will be returned. Specify 0 to start with the first record in the database.
[in]	maxRecordsToReturn	The maximum number of records to return in the response. 0 indicates that there is no limit.
[in]	applicationName	The ApplicationName of the Applications to return. Supports the syntax used by the LIKE FilterOperator. See UaString::like() for more details. Not used as filter if an empty string is specified. The filter is only applied to the default ApplicationName.
[in]	applicationUri	The ApplicationUri of the Servers to return. Supports the syntax used by the LIKE FilterOperator. See UaString::like() for more details. Not used as filter if an empty string is specified.
[in]	productUri	The ProductUri of the Servers to return. Supports the syntax used by the LIKE FilterOperator. See UaString::like() for more details. Not used as filter if an empty string is specified.
[in]	serverCapabilities	The Servers returned shall support all of the server capabilities specified. If no server capabilities are provided this filter is not used.
[out]	lastCounterResetTime	The last time the counters were reset.
[out]	servers	A list of Servers which meet the filter criteria. The ServerOnNetwork structure contains the following information: RecordId: A unique identifier for the record. This can be used to fetch the next batch of servers in a subsequent call. ServerName: The name of the Server. This is typically the ApplicationName for the Server. DiscoveryUrl: The URL of the discovery Endpoint. ServerCapabilities: The list of server capabilities supported by the Server.

UaStatus UaClientSdk::UaDiscovery::queryDirectory	(	ServiceSettings &	serviceSettings,
		const UaString &	sGdsURL,
		SessionConnectInfo &	sessionConnectInfo,
		SessionSecurityInfo &	sessionSecurityInfo,
		OpcUa_UInt32	startingRecordId,
		OpcUa_UInt32	maxRecordsToReturn,
		const UaString &	applicationName,
		const UaString &	applicationUri,
		const UaString &	productUri,
		const UaStringArray &	serverCapabilities,
		UaDateTime &	lastCounterResetTime,
		UaServerOnNetworks &	servers
	)

Get a filtered list of servers known by the Directory in a global discovery server.

Used to access the method QueryServers of the Directory object in a Global Discovery Server (GDS). The method is defined by the DirectoryType in the GDS information model.

The necessary information to connected to the GDS must be passed in. Any Client is able to call the method on the GDS, however, the set of results returned may be restricted based on the Client’s user credentials. Therefore it may be required to configure the sessionSecurityInfo with the right user token.

It may be necessary to call this method several times to get all results from the GDS. The behaviour can be controlled with the parameters startingRecordId and maxRecordsToReturn. The ServerOnNetwork structure returned in the parameter servers contains the RecordId of the returned server. It can be used to calculate the startingRecordId for the next call to queryDirectory. If the returned value in lastCounterResetTime is after the first call to queryDirectory, it may make sense to start over from beginning since the list of registered servers was changed. The startingRecordId for the first call is 0.

The results can be filtered with the parameters applicationName, applicationUri, productUri and serverCapabilities. Filters are combined in an AND operation. The serverCapabilities parameter is an array and a Server will pass this filter if it supports all of the specified capabilities. The other filter parameters are strings where the syntax of the LIKE FilterOperator can be used. See UaString::like() for more details.

Parameters

[in,out]	serviceSettings	The general service settings like timeout. See ServiceSettings for more details.
[in]	sGdsURL	The URL identifying an OPC UA GDS Directory Server. UA TCP: opc.tcp://MACHINE:4840 HTTPS with UA Binary: https://MACHINE/ServerName
[in,out]	sessionConnectInfo	The client defined session connect settings. See SessionConnectInfo for more info.
[in,out]	sessionSecurityInfo	The client defined session security settings. See SessionSecurityInfo for more info.
[in]	startingRecordId	Only records with an identifier greater than this number will be returned. Specify 0 to start with the first record in the database.
[in]	maxRecordsToReturn	The maximum number of records to return in the response. 0 indicates that there is no limit.
[in]	applicationName	The ApplicationName of the Applications to return. Supports the syntax used by the LIKE FilterOperator. See UaString::like() for more details. Not used if an empty string is specified. The filter is only applied to the default ApplicationName.
[in]	applicationUri	The ApplicationUri of the Servers to return. Supports the syntax used by the LIKE FilterOperator. See UaString::like() for more details. Not used if an empty string is specified.
[in]	productUri	The ProductUri of the Servers to return. Supports the syntax used by the LIKE FilterOperator. See UaString::like() for more details. Not used if an empty string is specified.
[in]	serverCapabilities	The Servers returned shall support all of the server capabilities specified. If no server capabilities are provided this filter is not used.
[out]	lastCounterResetTime	The last time the counters were reset.
[out]	servers	A list of Servers which meet the filter criteria. The ServerOnNetwork structure contains the following information: RecordId: A unique identifier for the record. This can be used to fetch the next batch of servers in a subsequent call. ServerName: The name of the Server. This is typically the ApplicationName for the Server. DiscoveryUrl: The URL of the discovery Endpoint. ServerCapabilities: The list of server capabilities supported by the Server.

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

D:/work/uasdkcpp/src/uaclient/uaclientcpp/uadiscovery.h
D:/work/uasdkcpp/src/uaclient/uaclientcpp/uadiscovery.cpp

Public Member Functions

Detailed Description

Member Function Documentation