#ifndef _QmfAgent_ #define _QmfAgent_ /* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ #include "qmf/QmfImportExport.h" namespace qmf { class AgentImpl; class Connection; class ObjectId; class AgentObject; class Value; class Event; class SchemaObjectClass; /** * AgentListener is used by agents that select the internalStore=false option (see Agent * constructor) or by agents that wish to provide access control for queries and methods. * * \ingroup qmfapi */ class AgentListener { QMF_EXTERN virtual ~AgentListener(); /** * allowQuery is called before a query operation is executed. If true is returned * by this function, the query will proceed. If false is returned, the query will * be forbidden. * * @param q The query being requested. * @param userId The authenticated identity of the user requesting the query. */ virtual bool allowQuery(const Query& q, const char* userId); /** * allowMethod is called before a method call is executed. If true is returned * by this function, the method call will proceed. If false is returned, the method * call will be forbidden. * * @param name The name of the method being called. * @param args A value object (of type "map") that contains both input and output arguments. * @param oid The objectId that identifies the instance of the object being called. * @param cls The Schema describing the object being called. * @param userId The authenticated identity of the requesting user. */ virtual bool allowMethod(const char* name, const Value& args, const ObjectId& oid, const SchemaObjectClass& cls, const char* userId); /** * query is called when the agent receives a query request. The handler must invoke * Agent::queryResponse zero or more times (using the supplied context) followed by * a single invocation of Agent::queryComplete. These calls do not need to be made * synchronously in the context of this function. They may occur before or after this * function returns. * * This function will only be invoked if internalStore=false in the Agent's constructor. * * @param context A context value to use in resulting calls to queryResponse and quertComplete. * @param q The query requested by the console. * @param userId the authenticated identity of the user requesting the query. */ virtual void query(uint32_t context, const Query& q, const char* userId); /** * syncStart is called when a console requests a standing query. This function must * behave exactly like AgentListener::query (i.e. send zero or more responses followed * by a queryComplete) except it then remembers the context and the query and makes * subsequent queryResponse calls whenever appropriate according the the query. * * The standing query shall stay in effect until syncStop is called with the same context * value or until a specified period of time elapses without receiving a syncTouch for the * context. * * This function will only be invoked if internalStore=false in the Agent's constructor. * * @param context A context value to use in resulting calls to queryResponse and queryComplete. * @param q The query requested by the console. * @param userId the authenticated identity of the user requesting the query. */ virtual void syncStart(uint32_t context, const Query& q, const char* userId); /** * syncTouch is called when the console that requested a standing query refreshes its * interest in the query. The console must periodically "touch" a standing query to keep * it alive. This prevents standing queries from accumulating when the console disconnects * before it can stop the query. * * This function will only be invoked if internalStore=false in the Agent's constructor. * * @param context The context supplied in a previous call to syncStart. * @param userId The authenticated identity of the requesting user. */ virtual void syncTouch(uint32_t context, const char* userId); /** * syncStop is called when the console that requested a standing query no longer wishes to * receive data associated with that query. The application shall stop processing this * query and shall remove its record of the context value. * * This function will only be invoked if internalStore=false in the Agent's constructor. * * @param context The context supplied in a previous call to syncStart. * @param userId The authenticated identity of the requesting user. */ virtual void syncStop(uint32_t context, const char* userId); /** * methodCall is called when a console invokes a method on a QMF object. The application * must call Agent::methodResponse once in response to this function. The response does * not need to be called synchronously in the context of this function. It may be called * before or after this function returns. * * This function will only be invoked if internalStore=false in the Agent's constructor. * * @param context A context value to use in resulting call to methodResponse. * @param name The name of the method being called. * @param args A value object (of type "map") that contains both input and output arguments. * @param oid The objectId that identifies the instance of the object being called. * @param cls The Schema describing the object being called. * @param userId The authenticated identity of the requesting user. */ virtual void methodCall(uint32_t context, const char* name, Value& args, const ObjectId& oid, const SchemaObjectClass& cls, const char* userId); }; /** * The Agent class is the QMF Agent portal. It should be instantiated once and associated with a * Connection (setConnection) to connect an agent to the QMF infrastructure. * * \ingroup qmfapi */ class Agent { public: /** * Create an instance of the Agent class. * * @param label An optional string label that can be used to identify the agent. * * @param internalStore If true, objects shall be tracked internally by the agent. * If false, the user of the agent must track the objects. * If the agent is tracking the objects, queries and syncs are handled by * the agent. The only involvement the user has is to optionally authorize * individual operations. If the user is tracking the objects, the user code * must implement queries and syncs (standing queries). * * @param listener A pointer to a class that implements the AgentListener interface. * This must be supplied if any of the following conditions are true: * - The agent model contains methods * - The user wishes to individually authorize query and sync operations. * - internalStore = false */ QMF_EXTERN Agent(char* label="qmfa", bool internalStore=true, AgentListener* listener=0); /** * Destroy an instance of the Agent class. */ QMF_EXTERN ~Agent(); /** * Set the persistent store file. This file, if specified, is used to store state information * about the Agent. For example, if object-ids must be persistent across restarts of the Agent * program, this file path must be supplied. * * @param path Full path to a file that is both writable and readable by the Agent program. */ QMF_EXTERN void setStoreDir(const char* path); /** * Provide a connection (to a Qpid broker) over which the agent can communicate. * * @param conn Pointer to a Connection object. */ QMF_EXTERN void setConnection(Connection* conn); /** * Register a class schema (object or event) with the agent. The agent must have a registered * schema for an object class or an event class before it can handle objects or events of that * class. * * @param cls Pointer to the schema structure describing the class. */ QMF_EXTERN void registerClass(SchemaObjectClass* cls); QMF_EXTERN void registerClass(SchemaEventClass* cls); /** * Add an object to the agent (for internal storage mode only). * * @param obj Reference to the object to be managed by the agent. * * @param persistent Iff true, the object ID assigned to the object shall indicate persistence * (i.e. the object ID shall be the same across restarts of the agent program). * * @param oid 64-bit value for the oid (if zero, the agent will assign the value). * * @param oidLo 32-bit value for the lower 32-bits of the oid. * * @param oidHi 32-bit value for the upper 32-bits of the oid. */ QMF_EXTERN const ObjectId* addObject(AgentObject& obj, bool persistent=false, uint64_t oid=0); QMF_EXTERN const ObjectId* addObject(AgentObject& obj, bool persistent, uint32_t oidLo, uint32_t oidHi); /** * Allocate an object ID for an object (for external storage mode only). * * @param persistent Iff true, the object ID allocated shall indicate persistence * (i.e. the object ID shall be the same across restarts of the agent program). * * @param oid 64-bit value for the oid (if zero, the agent will assign the value). * * @param oidLo 32-bit value for the lower 32-bits of the oid. * * @param oidHi 32-bit value for the upper 32-bits of the oid. */ QMF_EXTERN const ObjectId* allocObjectId(bool persistent=false, uint64_t oid=0); QMF_EXTERN const ObjectId* allocObjectId(bool persistent, uint32_t oidLo, uint32_t oidHi); /** * Raise a QMF event. * * @param event Reference to an event object to be raised to the QMF infrastructure. */ QMF_EXTERN void raiseEvent(Event& event); /** * Provide a response to a query (for external storage mode only). * * @param context The context value supplied in the query (via the AgentListener interface). * * @param object A reference to the agent that matched the query criteria. * * @param prop If true, transmit the property attributes of this object. * * @param stat If true, transmit the statistic attributes of this object. */ QMF_EXTERN void queryResponse(uint32_t context, AgentObject& object, bool prop = true, bool stat = true); /** * Indicate that a query (or the initial dump of a sync) is complete (for external storage mode only). * * @param context The context value supplied in the query/sync (via the AgentListener interface). */ QMF_EXTERN void queryComplete(uint32_t context); /** * Provide the response to a method call. * * @param context The context value supplied in the method request (via the AgentListener interface). * * @param args The argument list from the method call. Must include the output arguments (may include * the input arguments). * * @param status Numerical return status: zero indicates no error, non-zero indicates error. * * @param exception Pointer to an exception value. If status is non-zero, the exception value is * sent to the caller. It is optional (i.e. leave the pointer as 0), or may be * set to any legal value. A string may be supplied, but an unmanaged object of * any schema may also be passed. */ QMF_EXTERN void methodResponse(uint32_t context, const Value& args, uint32_t status=0, const Value* exception=0); private: AgentImpl* impl; }; } #endif