open62541/src/server/ua_services.h

/* This Source Code Form is subject to the terms of the Mozilla Public 
* License, v. 2.0. If a copy of the MPL was not distributed with this 
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 
#ifndef UA_SERVICES_H_
#define UA_SERVICES_H_

#ifdef __cplusplus
extern "C" {
#endif

#include "ua_server.h"
#include "ua_session.h"
#include "ua_nodes.h"

/**
 * .. _services:
 *
 * Services
 * ========
 *
 * In OPC UA, all communication is based on service calls, each consisting of a
 * request and a response message. These messages are defined as data structures
 * with a binary encoding and listed in :ref:`generated-types`. Since all
 * Services are pre-defined in the standard, they cannot be modified by the
 * user. But you can use the :ref:`Call <method-services>` service to invoke
 * user-defined methods on the server.
 *
 * The following service signatures are internal and *not visible to users*.
 * Still, we present them here for an overview of the capabilities of OPC UA.
 * Please refer to the :ref:`client` and :ref:`server` API where the services
 * are exposed to end users. Please see part 4 of the OPC UA standard for the
 * authoritative definition of the service and their behaviour. */
/* Most services take as input the server, the current session and pointers to
 * the request and response structures. Possible error codes are returned as
 * part of the response. */
typedef void (*UA_Service)(UA_Server*, UA_Session*,
                           const void *request, void *response);

/**
 * Discovery Service Set
 * ---------------------
 * This Service Set defines Services used to discover the Endpoints implemented
 * by a Server and to read the security configuration for those Endpoints. */
void Service_FindServers(UA_Server *server, UA_Session *session,
                         const UA_FindServersRequest *request,
                         UA_FindServersResponse *response);

/* Returns the Endpoints supported by a Server and all of the configuration
 * information required to establish a SecureChannel and a Session. */
void Service_GetEndpoints(UA_Server *server, UA_Session *session,
                          const UA_GetEndpointsRequest *request,
                          UA_GetEndpointsResponse *response);

#ifdef UA_ENABLE_DISCOVERY
/* Registers a remote server in the local discovery service. */
void Service_RegisterServer(UA_Server *server, UA_Session *session,
                            const UA_RegisterServerRequest *request,
                            UA_RegisterServerResponse *response);
#endif

/**
 * SecureChannel Service Set
 * -------------------------
 * This Service Set defines Services used to open a communication channel that
 * ensures the confidentiality and Integrity of all Messages exchanged with the
 * Server. */
/* Open or renew a SecureChannel that can be used to ensure Confidentiality and
 * Integrity for Message exchange during a Session. */
void Service_OpenSecureChannel(UA_Server *server, UA_Connection *connection,
                               const UA_OpenSecureChannelRequest *request,
                               UA_OpenSecureChannelResponse *response);

/* Used to terminate a SecureChannel. */
void Service_CloseSecureChannel(UA_Server *server, UA_SecureChannel *channel);

/**
 * Session Service Set
 * -------------------
 * This Service Set defines Services for an application layer connection
 * establishment in the context of a Session. */
/* Used by an OPC UA Client to create a Session and the Server returns two
 * values which uniquely identify the Session. The first value is the sessionId
 * which is used to identify the Session in the audit logs and in the Server's
 * address space. The second is the authenticationToken which is used to
 * associate an incoming request with a Session. */
void Service_CreateSession(UA_Server *server, UA_SecureChannel *channel,
                           const UA_CreateSessionRequest *request,
                           UA_CreateSessionResponse *response);

/* Used by the Client to submit its SoftwareCertificates to the Server for
 * validation and to specify the identity of the user associated with the
 * Session. This Service request shall be issued by the Client before it issues
 * any other Service request after CreateSession. Failure to do so shall cause
 * the Server to close the Session. */
void Service_ActivateSession(UA_Server *server, UA_SecureChannel *channel,
                             UA_Session *session,
                             const UA_ActivateSessionRequest *request,
                             UA_ActivateSessionResponse *response);

/* Used to terminate a Session. */
void Service_CloseSession(UA_Server *server, UA_Session *session,
                          const UA_CloseSessionRequest *request,
                          UA_CloseSessionResponse *response);

/* Not Implemented: Service_Cancel */

/**
 * NodeManagement Service Set
 * --------------------------
 * This Service Set defines Services to add and delete AddressSpace Nodes and
 * References between them. All added Nodes continue to exist in the
 * AddressSpace even if the Client that created them disconnects from the
 * Server. */
/* Used to add one or more Nodes into the AddressSpace hierarchy. */
void Service_AddNodes(UA_Server *server, UA_Session *session,
                      const UA_AddNodesRequest *request,
                      UA_AddNodesResponse *response);

/* Used to add one or more References to one or more Nodes. */
void Service_AddReferences(UA_Server *server, UA_Session *session,
                           const UA_AddReferencesRequest *request,
                           UA_AddReferencesResponse *response);

/* Used to delete one or more Nodes from the AddressSpace. */
void Service_DeleteNodes(UA_Server *server, UA_Session *session,
                         const UA_DeleteNodesRequest *request,
                         UA_DeleteNodesResponse *response);

/* Used to delete one or more References of a Node. */
void Service_DeleteReferences(UA_Server *server, UA_Session *session,
                              const UA_DeleteReferencesRequest *request,
                              UA_DeleteReferencesResponse *response);

/**
 * .. _view-services:
 *
 * View Service Set
 * ----------------
 * Clients use the browse Services of the View Service Set to navigate through
 * the AddressSpace or through a View which is a subset of the AddressSpace. */
/* Used to discover the References of a specified Node. The browse can be
 * further limited by the use of a View. This Browse Service also supports a
 * primitive filtering capability. */
void Service_Browse(UA_Server *server, UA_Session *session,
                    const UA_BrowseRequest *request,
                    UA_BrowseResponse *response);

/* Used to request the next set of Browse or BrowseNext response information
 * that is too large to be sent in a single response. "Too large" in this
 * context means that the Server is not able to return a larger response or that
 * the number of results to return exceeds the maximum number of results to
 * return that was specified by the Client in the original Browse request. */
void Service_BrowseNext(UA_Server *server, UA_Session *session,
                        const UA_BrowseNextRequest *request,
                        UA_BrowseNextResponse *response);

/* Used to translate textual node paths to their respective ids. */
void Service_TranslateBrowsePathsToNodeIds(UA_Server *server, UA_Session *session,
             const UA_TranslateBrowsePathsToNodeIdsRequest *request,
             UA_TranslateBrowsePathsToNodeIdsResponse *response);

/* Used by Clients to register the Nodes that they know they will access
 * repeatedly (e.g. Write, Call). It allows Servers to set up anything needed so
 * that the access operations will be more efficient. */
void Service_RegisterNodes(UA_Server *server, UA_Session *session,
                           const UA_RegisterNodesRequest *request,
                           UA_RegisterNodesResponse *response);

/* This Service is used to unregister NodeIds that have been obtained via the
 * RegisterNodes service. */
void Service_UnregisterNodes(UA_Server *server, UA_Session *session,
                             const UA_UnregisterNodesRequest *request,
                             UA_UnregisterNodesResponse *response);

/**
 * Query Service Set
 * -----------------
 * This Service Set is used to issue a Query to a Server. OPC UA Query is
 * generic in that it provides an underlying storage mechanism independent Query
 * capability that can be used to access a wide variety of OPC UA data stores
 * and information management systems. OPC UA Query permits a Client to access
 * data maintained by a Server without any knowledge of the logical schema used
 * for internal storage of the data. Knowledge of the AddressSpace is
 * sufficient. */
/* Not Implemented: Service_QueryFirst */
/* Not Impelemented: Service_QueryNext */

/**
 * Attribute Service Set
 * ---------------------
 * This Service Set provides Services to access Attributes that are part of
 * Nodes. */
/* Used to read one or more Attributes of one or more Nodes. For constructed
 * Attribute values whose elements are indexed, such as an array, this Service
 * allows Clients to read the entire set of indexed values as a composite, to
 * read individual elements or to read ranges of elements of the composite. */
void Service_Read(UA_Server *server, UA_Session *session,
                  const UA_ReadRequest *request,
                  UA_ReadResponse *response);

/* Used to write one or more Attributes of one or more Nodes. For constructed
 * Attribute values whose elements are indexed, such as an array, this Service
 * allows Clients to write the entire set of indexed values as a composite, to
 * write individual elements or to write ranges of elements of the composite. */
void Service_Write(UA_Server *server, UA_Session *session,
                   const UA_WriteRequest *request,
                   UA_WriteResponse *response);

/* Not Implemented: Service_HistoryRead */
/* Not Implemented: Service_HistoryUpdate */

/**
 * .. _method-services:
 *
 * Method Service Set
 * ------------------
 * The Method Service Set defines the means to invoke methods. A method shall be
 * a component of an Object. See the section on :ref:`MethodNodes <methodnode>`
 * for more information. */
/* Used to call (invoke) a list of Methods. Each method call is invoked within
 * the context of an existing Session. If the Session is terminated, the results
 * of the method's execution cannot be returned to the Client and are
 * discarded. */
void Service_Call(UA_Server *server, UA_Session *session,
                  const UA_CallRequest *request,
                  UA_CallResponse *response);

/**
 * MonitoredItem Service Set
 * -------------------------
 * Clients define MonitoredItems to subscribe to data and Events. Each
 * MonitoredItem identifies the item to be monitored and the Subscription to use
 * to send Notifications. The item to be monitored may be any Node Attribute. */
/* Used to create and add one or more MonitoredItems to a Subscription. A
 * MonitoredItem is deleted automatically by the Server when the Subscription is
 * deleted. Deleting a MonitoredItem causes its entire set of triggered item
 * links to be deleted, but has no effect on the MonitoredItems referenced by
 * the triggered items. */
void Service_CreateMonitoredItems(UA_Server *server, UA_Session *session,
                                  const UA_CreateMonitoredItemsRequest *request, 
                                  UA_CreateMonitoredItemsResponse *response);

/* Used to remove one or more MonitoredItems of a Subscription. When a
 * MonitoredItem is deleted, its triggered item links are also deleted. */
void Service_DeleteMonitoredItems(UA_Server *server, UA_Session *session,
                                  const UA_DeleteMonitoredItemsRequest *request,
                                  UA_DeleteMonitoredItemsResponse *response);

void Service_ModifyMonitoredItems(UA_Server *server, UA_Session *session,
                                  const UA_ModifyMonitoredItemsRequest *request,
                                  UA_ModifyMonitoredItemsResponse *response);

/* Used to set the monitoring mode for one or more MonitoredItems of a
   Subscription. */
void Service_SetMonitoringMode(UA_Server *server, UA_Session *session,
                               const UA_SetMonitoringModeRequest *request,
                               UA_SetMonitoringModeResponse *response);

/* Not Implemented: Service_SetTriggering */

/**
 * Subscription Service Set
 * ------------------------
 * Subscriptions are used to report Notifications to the Client. */
/* Used to create a Subscription. Subscriptions monitor a set of MonitoredItems
 * for Notifications and return them to the Client in response to Publish
 * requests. */
void Service_CreateSubscription(UA_Server *server, UA_Session *session,
                                const UA_CreateSubscriptionRequest *request,
                                UA_CreateSubscriptionResponse *response);

/* Used to modify a Subscription. */
void Service_ModifySubscription(UA_Server *server, UA_Session *session,
                                const UA_ModifySubscriptionRequest *request,
                                UA_ModifySubscriptionResponse *response);

/* Used to enable sending of Notifications on one or more Subscriptions. */
void Service_SetPublishingMode(UA_Server *server, UA_Session *session,
                               const UA_SetPublishingModeRequest *request,
                               UA_SetPublishingModeResponse *response);

/* Used for two purposes. First, it is used to acknowledge the receipt of
 * NotificationMessages for one or more Subscriptions. Second, it is used to
 * request the Server to return a NotificationMessage or a keep-alive
 * Message.
 *
 * Note that the service signature is an exception and does not contain a
 * pointer to a PublishResponse. That is because the service queues up publish
 * requests internally and sends responses asynchronously based on timeouts. */
void Service_Publish(UA_Server *server, UA_Session *session,
                     const UA_PublishRequest *request, UA_UInt32 requestId);

/* Requests the Subscription to republish a NotificationMessage from its
 * retransmission queue. */
void Service_Republish(UA_Server *server, UA_Session *session,
                       const UA_RepublishRequest *request,
                       UA_RepublishResponse *response);

/* Invoked to delete one or more Subscriptions that belong to the Client's
 * Session. */
void Service_DeleteSubscriptions(UA_Server *server, UA_Session *session,
                                 const UA_DeleteSubscriptionsRequest *request,
                                 UA_DeleteSubscriptionsResponse *response);

/* Not Implemented: Service_TransferSubscription */

#ifdef __cplusplus
} // extern "C"
#endif

#endif /* UA_SERVICES_H_ */