#include <resourcebase.h>

Inheritance diagram for Akonadi::ResourceBase:

Signals
void	attributesSynchronized (qlonglong collectionId)

void	collectionTreeSynchronized ()

void	nameChanged (const QString &name)

void	synchronized ()

Signals inherited from Akonadi::AgentBase
void	abortRequested ()

void	advancedStatus (const QVariantMap &status)

void	agentNameChanged (const QString &name)

void	configurationDialogAccepted ()

void	configurationDialogRejected ()

void	error (const QString &message)

void	onlineChanged (bool online)

void	percent (int progress)

void	reloadConfiguration ()

void	status (int status, const QString &message=QString())

void	warning (const QString &message)

Public Member Functions
QString	name () const

void	setAutomaticProgressReporting (bool enabled)

void	setName (const QString &name)

Public Member Functions inherited from Akonadi::AgentBase
QString	agentName () const

virtual void	cleanup ()

QString	identifier () const

virtual int	progress () const

virtual QString	progressMessage () const

void	registerObserver (Observer *observer)

void	setAgentName (const QString &name)

virtual int	status () const

virtual QString	statusMessage () const

WId	winIdForDialogs () const

Static Public Member Functions
template<typename T >
static int	init (int argc, char **argv)

Static Public Member Functions inherited from Akonadi::AgentBase
static KComponentData	componentData ()

template<typename T >
static int	init (int argc, char **argv)

Protected Types
enum	SchedulePriority { Prepend, AfterChangeReplay, Append }

Protected Slots
void	abortActivity ()

QString	dumpResourceToString () const

void	retrieveCollectionAttributes (const Akonadi::Collection &collection)

virtual void	retrieveCollections ()=0

virtual bool	retrieveItem (const Akonadi::Item &item, const QSet< QByteArray > &parts)=0

virtual void	retrieveItems (const Akonadi::Collection &collection)=0

Protected Member Functions
	ResourceBase (const QString &id)

	~ResourceBase ()

void	cancelTask ()

void	cancelTask (const QString &error)

void	changeCommitted (const Item &item)

void	changeCommitted (const Collection &collection)

void	changesCommitted (const Item::List &items)

void	clearCache ()

void	collectionAttributesRetrieved (const Collection &collection)

void	collectionsRetrievalDone ()

void	collectionsRetrieved (const Collection::List &collections)

void	collectionsRetrievedIncremental (const Collection::List &changedCollections, const Collection::List &removedCollections)

Collection	currentCollection () const

Item	currentItem () const

void	deferTask ()

void	doSetOnline (bool online)

void	dumpMemoryInfo () const

QString	dumpMemoryInfoToString () const

QString	dumpNotificationListToString () const

QString	dumpSchedulerToString () const

void	invalidateCache (const Collection &collection)

void	itemRetrieved (const Item &item)

void	itemsRetrievalDone ()

void	itemsRetrieved (const Item::List &items)

void	itemsRetrievedIncremental (const Item::List &changedItems, const Item::List &removedItems)

void	scheduleCustomTask (QObject receiver, const char method, const QVariant &argument, SchedulePriority priority=Append)

void	setCollectionStreamingEnabled (bool enable)

void	setHierarchicalRemoteIdentifiersEnabled (bool enable)

void	setItemStreamingEnabled (bool enable)

void	setItemSynchronizationFetchScope (const ItemFetchScope &fetchScope)

void	setItemTransactionMode (ItemSync::TransactionMode mode)

void	setTotalItems (int amount)

void	synchronize ()

void	synchronizeCollection (qint64 id)

void	synchronizeCollection (qint64 id, bool recursive)

void	synchronizeCollectionAttributes (qint64 id)

void	synchronizeCollectionTree ()

void	taskDone ()

Protected Member Functions inherited from Akonadi::AgentBase
	AgentBase (const QString &id)

	~AgentBase ()

virtual void	aboutToQuit ()

void	changeProcessed ()

ChangeRecorder *	changeRecorder () const

KSharedConfigPtr	config ()

bool	isOnline () const

void	setNeedsNetwork (bool needsNetwork)

void	setOnline (bool state)

Additional Inherited Members
Public Types inherited from Akonadi::AgentBase
enum	Status { Idle = 0, Running, Broken, NotConfigured }

Public Slots inherited from Akonadi::AgentBase
virtual void	configure (WId windowId)

Detailed Description

The base class for all Akonadi resources.

This class should be used as a base class by all resource agents, because it encapsulates large parts of the protocol between resource agent, agent manager and the Akonadi storage.

It provides many convenience methods to make implementing a new Akonadi resource agent as simple as possible.

How to write a resource

The following provides an overview of what you need to do to implement your own Akonadi resource. In the following, the term 'backend' refers to the entity the resource connects with Akonadi, be it a single file or a remote server.

Todo:: Complete this (online/offline state management)

Basic Resource Framework

The following is needed to create a new resource:

A new class deriving from Akonadi::ResourceBase, implementing at least all pure-virtual methods, see below for further details.
call init() in your main() function.
a .desktop file similar to the following example
[Desktop Entry]

Encoding=UTF-8

Name=My Akonadi Resource

Type=AkonadiResource

Exec=akonadi_my_resource

Icon=my-icon

X-Akonadi-MimeTypes=<supported-mimetypes>

X-Akonadi-Capabilities=Resource

X-Akonadi-Identifier=akonadi_my_resource

Handling PIM Items

To follow item changes in the backend, the following steps are necessary:

Implement retrieveItems() to synchronize all items in the given collection. If the backend supports incremental retrieval, implementing support for that is recommended to improve performance.
Convert the items provided by the backend to Akonadi items. This typically happens either in retrieveItems() if you retrieved the collection synchronously (not recommended for network backends) or in the result slot of the asynchronous retrieval job. Converting means to create Akonadi::Item objects for every retrieved item. It's very important that every object has its remote identifier set.
Call itemsRetrieved() or itemsRetrievedIncremental() respectively with the item objects created above. The Akonadi storage will then be updated automatically. Note that it is usually not necessary to manipulate any item in the Akonadi storage manually.

To fetch item data on demand, the method retrieveItem() needs to be reimplemented. Fetch the requested data there and call itemRetrieved() with the result item.

To write local changes back to the backend, you need to re-implement the following three methods:

itemAdded()
itemChanged()
itemRemoved()

Note that these three functions don't get the full payload of the items by default, you need to change the item fetch scope of the change recorder to fetch the full payload. This can be expensive with big payloads, though.
Once you have handled changes in these methods, call changeCommitted(). These methods are called whenever a local item related to this resource is added, modified or deleted. They are only called if the resource is online, otherwise all changes are recorded and replayed as soon the resource is online again.

Handling Collections

To follow collection changes in the backend, the following steps are necessary:

Implement retrieveCollections() to retrieve collections from the backend. If the backend supports incremental collections updates, implementing support for that is recommended to improve performance.
Convert the collections of the backend to Akonadi collections. This typically happens either in retrieveCollections() if you retrieved the collection synchronously (not recommended for network backends) or in the result slot of the asynchronous retrieval job. Converting means to create Akonadi::Collection objects for every retrieved collection. It's very important that every object has its remote identifier and its parent remote identifier set.
Call collectionsRetrieved() or collectionsRetrievedIncremental() respectively with the collection objects created above. The Akonadi storage will then be updated automatically. Note that it is usually not necessary to manipulate any collection in the Akonadi storage manually.

To write local collection changes back to the backend, you need to re-implement the following three methods:

collectionAdded()
collectionChanged()
collectionRemoved() Once you have handled changes in these methods call changeCommitted(). These methods are called whenever a local collection related to this resource is added, modified or deleted. They are only called if the resource is online, otherwise all changes are recorded and replayed as soon the resource is online again.

Todo:: Convenience base class for collection-less resources

Definition at line 147 of file resourcebase.h.

Member Enumeration Documentation

enum Akonadi::ResourceBase::SchedulePriority

protected

Describes the scheduling priority of a task that has been queued for execution.

See also: scheduleCustomTask

Since: 4.4

Enumerator
Prepend	The task will be executed as soon as the current task has finished.
AfterChangeReplay	The task is scheduled after the last ChangeReplay task in the queue.
Append	The task will be executed after all tasks currently in the queue are finished.

Definition at line 602 of file resourcebase.h.

Constructor & Destructor Documentation

ResourceBase::ResourceBase ( const QString & id )

protected

Creates a base resource.

Parameters

id	The instance id of the resource.

Definition at line 387 of file resourcebase.cpp.

ResourceBase::~ResourceBase ( )

protected

Destroys the base resource.

Definition at line 447 of file resourcebase.cpp.

Member Function Documentation

void Akonadi::ResourceBase::abortActivity ( )

protectedslot

Abort any activity in progress in the backend.

By default this method does nothing.

Since: 4.6

Definition at line 1128 of file resourcebase.cpp.

void Akonadi::ResourceBase::attributesSynchronized ( qlonglong collectionId )

signal

Emitted when a collection attributes synchronization has been completed.

Parameters

collectionId The identifier of the collection whose attributes got synchronized.

Since: 4.6

void ResourceBase::cancelTask ( )

protected

Stops the execution of the current task and continues with the next one.

Definition at line 923 of file resourcebase.cpp.

void ResourceBase::cancelTask ( const QString & error )

protected

Stops the execution of the current task and continues with the next one.

Additionally an error message is emitted.

Parameters

error additional error message to be emitted

Definition at line 952 of file resourcebase.cpp.

void ResourceBase::changeCommitted ( const Item & item )

protected

Resets the dirty flag of the given item and updates the remote id.

Call whenever you have successfully written changes back to the server. This implicitly calls changeProcessed().

Parameters

item	The changed item.

Definition at line 622 of file resourcebase.cpp.

void ResourceBase::changeCommitted ( const Collection & collection )

protected

Call whenever you have successfully handled or ignored a collection change notification.

This will update the remote identifier of collection if necessary, as well as any other collection attributes. This implicitly calls changeProcessed().

Parameters

collection The collection which changes have been handled.

Definition at line 636 of file resourcebase.cpp.

void ResourceBase::changesCommitted ( const Item::List & items )

protected

Resets the dirty flag of all given items and updates remote ids.

Call whenever you have successfully written changes back to the server. This implicitly calls changeProcessed().

Parameters

items Changed items

Since: 4.11

Definition at line 627 of file resourcebase.cpp.

void ResourceBase::clearCache ( )

protected

Call this method to remove all items and collections of the resource from the server cache.

The method should not be used anymore

See also: invalidateCache()

Since: 4.3

Definition at line 888 of file resourcebase.cpp.

void ResourceBase::collectionAttributesRetrieved ( const Collection & collection )

protected

Call this method from retrieveCollectionAttributes() once the result is available.

Parameters

collection The collection whose attributes got retrieved.

Since: 4.6

Definition at line 552 of file resourcebase.cpp.

void ResourceBase::collectionsRetrievalDone ( )

protected

Call this method to indicate you finished synchronizing the collection tree.

This is not needed if you use the built in syncing without collection streaming and call collectionsRetrieved() or collectionRetrievedIncremental() instead. If collection streaming is enabled, call this method once all collections have been delivered using collectionsRetrieved() or collectionsRetrievedIncremental().

Definition at line 738 of file resourcebase.cpp.

void ResourceBase::collectionsRetrieved ( const Collection::List & collections )

protected

Call this to supply the full folder tree retrieved from the remote server.

Parameters

collections A list of collections.

See also: collectionsRetrievedIncremental()

Definition at line 689 of file resourcebase.cpp.

void ResourceBase::collectionsRetrievedIncremental	(	const Collection::List &	changedCollections,
		const Collection::List &	removedCollections
	)

protected

Call this to supply incrementally retrieved collections from the remote server.

Parameters

changedCollections	Collections that have been added or changed.
removedCollections	Collections that have been deleted.

See also: collectionsRetrieved()

Definition at line 705 of file resourcebase.cpp.

void Akonadi::ResourceBase::collectionTreeSynchronized ( )

signal

Emitted when a collection tree synchronization has been completed.

Since: 4.8

Collection ResourceBase::currentCollection ( ) const

protected

Returns the collection that is currently synchronized.

Note: Calling this method is only allowed during a collection synchronization task, that is directly or indirectly from retrieveItems().

Definition at line 900 of file resourcebase.cpp.

Item ResourceBase::currentItem ( ) const

protected

Returns the item that is currently retrieved.

Note: Calling this method is only allowed during fetching a single item, that is directly or indirectly from retrieveItem().

Definition at line 909 of file resourcebase.cpp.

void ResourceBase::deferTask ( )

protected

Stops the execution of the current task and continues with the next one.

The current task will be tried again later.

This can be used to delay the task processing until the resource has reached a safe state, e.g. login to a server succeeded.

Note: This does not change the order of tasks so if there is no task with higher priority e.g. a custom task added with Prepend the deferred task will be processed again.

Since: 4.3

Definition at line 959 of file resourcebase.cpp.

void ResourceBase::doSetOnline ( bool online )

protectedvirtual

Inherited from AgentBase.

Reimplemented from Akonadi::AgentBase.

Definition at line 965 of file resourcebase.cpp.

void ResourceBase::dumpMemoryInfo ( ) const

protected

Dumps memory usage information to stdout.

For now it outputs the result of glibc's mallinfo(). This is useful to check if your memory problems are due to poor management by glibc. Look for a high value on fsmblks when interpreting results. man mallinfo for more details.

Since: 4.11

Definition at line 1165 of file resourcebase.cpp.

QString ResourceBase::dumpMemoryInfoToString ( ) const

protected

Returns a string with memory usage information.

See also: dumpMemoryInfo()

Since: 4.11

Definition at line 1171 of file resourcebase.cpp.

QString ResourceBase::dumpNotificationListToString ( ) const

protected

Dump the contents of the current ChangeReplay.

Since: 4.8.1

Definition at line 1153 of file resourcebase.cpp.

QString Akonadi::ResourceBase::dumpResourceToString ( ) const

inlineprotectedslot

Dump resource internals, for debugging.

Since: 4.9

Definition at line 310 of file resourcebase.h.

QString ResourceBase::dumpSchedulerToString ( ) const

protected

Dump the state of the scheduler.

Since: 4.8.1

Definition at line 1159 of file resourcebase.cpp.

template<typename T >

static int Akonadi::ResourceBase::init	(	int	argc,
		char **	argv
	)

inlinestatic

Use this method in the main function of your resource application to initialize your resource subclass.

This method also takes care of creating a KApplication object and parsing command line arguments.

Note: In case the given class is also derived from AgentBase::Observer it gets registered as its own observer (see AgentBase::Observer), e.g. resourceInstance->registerObserver( resourceInstance );

class MyResource : public ResourceBase
{
  ...
};
int main( int argc, char **argv )
{
  return ResourceBase::init<MyResource>( argc, argv );
}

Parameters

argc	number of arguments
argv	string arguments

Definition at line 180 of file resourcebase.h.

void ResourceBase::invalidateCache ( const Collection & collection )

protected

Call this method to invalidate all cached content in collection.

The method should be used when the backend indicated that the cached content is no longer valid.

Parameters

collection parent of the content to be invalidated in cache

Since: 4.8

Definition at line 894 of file resourcebase.cpp.

void ResourceBase::itemRetrieved ( const Item & item )

protected

Call this method from retrieveItem() once the result is available.

Parameters

item	The retrieved item.

Definition at line 517 of file resourcebase.cpp.

void ResourceBase::itemsRetrievalDone ( )

protected

Call this method to indicate you finished synchronizing the current collection.

This is not needed if you use the built in syncing without item streaming and call itemsRetrieved() or itemsRetrievedIncremental() instead. If item streaming is enabled, call this method once all items have been delivered using itemsRetrieved() or itemsRetrievedIncremental().

See also: retrieveItems()

Definition at line 875 of file resourcebase.cpp.

void ResourceBase::itemsRetrieved ( const Item::List & items )

protected

Call this method to supply the full collection listing from the remote server.

Items not present in the list will be dropped from the Akonadi database.

If the remote server supports incremental listing, it's strongly recommended to use itemsRetrievedIncremental() instead.

Parameters

items A list of items.

See also: itemsRetrievedIncremental().

Definition at line 1040 of file resourcebase.cpp.

void ResourceBase::itemsRetrievedIncremental	(	const Item::List &	changedItems,
		const Item::List &	removedItems
	)

protected

Call this method to supply incrementally retrieved items from the remote server.

Parameters

changedItems	Items changed in the backend.
removedItems	Items removed from the backend.

Definition at line 1049 of file resourcebase.cpp.

QString ResourceBase::name ( ) const

Returns the name of the resource.

Definition at line 461 of file resourcebase.cpp.

void Akonadi::ResourceBase::nameChanged ( const QString & name )

signal

This signal is emitted whenever the name of the resource has changed.

Parameters

name	The new name of the resource.

void ResourceBase::retrieveCollectionAttributes ( const Akonadi::Collection & collection )

protectedslot

Retrieve the attributes of a single collection from the backend.

The collection to retrieve attributes for is provided as collection. Add the attributes parts and call collectionAttributesRetrieved() when done.

Parameters

collection The collection whose attributes should be retrieved.

See also: collectionAttributesRetrieved()

Since: 4.6

Definition at line 1123 of file resourcebase.cpp.

virtual void Akonadi::ResourceBase::retrieveCollections ( )

protectedpure virtualslot

Retrieve the collection tree from the remote server and supply it via collectionsRetrieved() or collectionsRetrievedIncremental().

See also: collectionsRetrieved(), collectionsRetrievedIncremental()

virtual bool Akonadi::ResourceBase::retrieveItem	(	const Akonadi::Item &	item,
		const QSet< QByteArray > &	parts
	)

protectedpure virtualslot

Retrieve a single item from the backend.

The item to retrieve is provided as item. Add the requested payload parts and call itemRetrieved() when done.

Parameters

item	The empty item whose payload should be retrieved. Use this object when delivering the result instead of creating a new item to ensure conflict detection will work.
parts	The item parts that should be retrieved.

Returns: false if there is an immediate error when retrieving the item.

See also: itemRetrieved()

virtual void Akonadi::ResourceBase::retrieveItems ( const Akonadi::Collection & collection )

protectedpure virtualslot

Retrieve all (new/changed) items in collection collection.

It is recommended to use incremental retrieval if the backend supports that and provide the result by calling itemsRetrievedIncremental(). If incremental retrieval is not possible, provide the full listing by calling itemsRetrieved( const Item::List& ). In any case, ensure that all items have a correctly set remote identifier to allow synchronizing with items already existing locally. In case you don't want to use the built-in item syncing code, store the retrieved items manually and call itemsRetrieved() once you are done.

Parameters

collection The collection whose items to retrieve.

See also: itemsRetrieved( const Item::List& ), itemsRetrievedIncremental(), itemsRetrieved(), currentCollection()

void ResourceBase::scheduleCustomTask	(	QObject *	receiver,
		const char *	method,
		const QVariant &	argument,
		SchedulePriority	priority = `Append`
	)

protected

Schedules a custom task in the internal scheduler.

It will be queued with all other tasks such as change replays and retrieval requests and eventually executed by calling the specified method. With the priority parameter the time of execution of the Task can be influenced.

See also: SchedulePriority

Parameters

receiver	The object the slot should be called on.
method	The name of the method (and only the name, not signature, not SLOT(...) macro), that should be called to execute this task. The method has to be a slot and take a QVariant as argument.
argument	A QVariant argument passed to the method specified above. Use this to pass task parameters.
priority	Priority of the task. Use this to influence the position in the execution queue.

Since: 4.4

Definition at line 1111 of file resourcebase.cpp.

void ResourceBase::setAutomaticProgressReporting ( bool enabled )

Enable or disable automatic progress reporting.

By default, it is enabled. When enabled, the resource will automatically emit the signals percent() and status() while syncing items or collections.

The automatic progress reporting is done on a per item / per collection basis, so if a finer granularity is desired, automatic reporting should be disabled and the subclass should emit the percent() and status() signals itself.

Parameters

enabled Whether or not automatic emission of the signals is enabled.

Since: 4.7

Definition at line 1147 of file resourcebase.cpp.

void ResourceBase::setCollectionStreamingEnabled ( bool enable )

protected

Enable collection streaming, that is collections don't have to be delivered at once as result of a retrieveCollections() call but can be delivered by multiple calls to collectionsRetrieved() or collectionsRetrievedIncremental().

When all collections have been retrieved, call collectionsRetrievalDone().

Parameters

enable true if collection streaming should be enabled, false by default

Definition at line 722 of file resourcebase.cpp.

void ResourceBase::setHierarchicalRemoteIdentifiersEnabled ( bool enable )

protected

Indicate the use of hierarchical remote identifiers.

This means that it is possible to have two different items with the same remoteId in different Collections.

This should be called in the resource constructor as needed.

Parameters

enable whether to enable use of hierarchical remote identifiers

Since: 4.4

Definition at line 1105 of file resourcebase.cpp.

void ResourceBase::setItemStreamingEnabled ( bool enable )

protected

Enable item streaming.

Item streaming is disabled by default.

Parameters

enable true if items are delivered in chunks rather in one big block.

Definition at line 1031 of file resourcebase.cpp.

void ResourceBase::setItemSynchronizationFetchScope ( const ItemFetchScope & fetchScope )

protected

Set the fetch scope applied for item synchronization.

By default, the one set on the changeRecorder() is used. However, it can make sense to specify a specialized fetch scope for synchronization to improve performance. The rule of thumb is to remove anything from this fetch scope that does not provide additional information regarding whether and item has changed or not. This is primarily relevant for backends not supporting incremental retrieval.

Parameters

fetchScope The fetch scope to use by the internal Akonadi::ItemSync instance.

See also: Akonadi::ItemSync

Since: 4.6

Definition at line 1139 of file resourcebase.cpp.

void ResourceBase::setItemTransactionMode ( ItemSync::TransactionMode mode )

protected

Set transaction mode for item sync'ing.

Parameters

mode	item transaction mode

See also: Akonadi::ItemSync::TransactionMode

Since: 4.6

Definition at line 1133 of file resourcebase.cpp.

void ResourceBase::setName ( const QString & name )

This method is used to set the name of the resource.

Definition at line 456 of file resourcebase.cpp.

void ResourceBase::setTotalItems ( int amount )

protected

Call this method when you want to use the itemsRetrieved() method in streaming mode and indicate the amount of items that will arrive that way.

Deprecated:

Use setItemStreamingEnabled( true ) + itemsRetrieved[Incremental]()

itemsRetrieved() instead.
Parameters

amount number of items that will arrive in streaming mode

Definition at line 1021 of file resourcebase.cpp.

void ResourceBase::synchronize ( )

protected

This method is called whenever the resource should start synchronize all data.

Definition at line 451 of file resourcebase.cpp.

void ResourceBase::synchronizeCollection ( qint64 id )

protected

This method is called whenever the collection with the given id shall be synchronized.

Definition at line 970 of file resourcebase.cpp.

void ResourceBase::synchronizeCollection	(	qint64	id,
		bool	recursive
	)

protected

This method is called whenever the collection with the given id shall be synchronized.

Parameters

recursive if true, a recursive synchronization is done

Definition at line 975 of file resourcebase.cpp.

void ResourceBase::synchronizeCollectionAttributes ( qint64 id )

protected

This method is called whenever the collection with the given id shall have its attributes synchronized.

Parameters

id	The id of the collection to synchronize

Since: 4.6

Definition at line 1001 of file resourcebase.cpp.

void ResourceBase::synchronizeCollectionTree ( )

protected

Refetches the Collections.

Definition at line 918 of file resourcebase.cpp.

void Akonadi::ResourceBase::synchronized ( )

signal

Emitted when a full synchronization has been completed.

void ResourceBase::taskDone ( )

protected

Indicate that the current task is finished.

Use this method from the slot called via scheduleCustomTaks(). As with all the other callbacks, make sure to either call taskDone() or cancelTask()/deferTask() on all exit paths, otherwise the resource will hang.

Since: 4.4

Definition at line 1117 of file resourcebase.cpp.

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

akonadi

Signals

Public Member Functions

Static Public Member Functions

Protected Types

Protected Slots

Protected Member Functions

Additional Inherited Members

Detailed Description

How to write a resource

Basic Resource Framework

Handling PIM Items

Handling Collections

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

akonadi

kdepimlibs API Reference

Search