Akonadi::ItemSerializerPlugin

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Akonadi::ItemSerializerPlugin Class Referenceabstract

#include <itemserializerplugin.h>

Public Member Functions

virtual ~ItemSerializerPlugin ()
 
virtual QSet< QByteArrayallowedForeignParts (const Item &item) const
 
virtual void apply (Item &item, const Item &other)
 
virtual QSet< QByteArrayavailableParts (const Item &item) const
 
virtual bool deserialize (Item &item, const QByteArray &label, QIODevice &data, int version)=0
 
virtual QSet< QByteArrayparts (const Item &item) const
 
virtual void serialize (const Item &item, const QByteArray &label, QIODevice &data, int &version)=0
 

Static Public Member Functions

static void overridePluginLookup (QObject *plugin)
 

Detailed Description

The base class for item type serializer plugins.

Serializer plugins convert between the payload of Akonadi::Item objects and a textual or binary representation of the actual content data. This allows to easily add support for new types to Akonadi.

The following example shows how to implement a serializer plugin for a new data type PimNote.

The PimNote data structure:

typedef struct {
QString author;
QDateTime dateTime;
QString text;
} PimNote;

The serializer plugin code:

#include <qplugin.h>
class SerializerPluginPimNote : public QObject, public Akonadi::ItemSerializerPlugin
{
public:
bool deserialize( Akonadi::Item& item, const QByteArray& label, QIODevice& data, int version )
{
// we don't handle versions in this example
Q_UNUSED(version)
// we work only on full payload
return false;
QDataStream stream( &data );
PimNote note;
stream >> note.author;
stream >> note.dateTime;
stream >> note.text;
item.setPayload<PimNote>( note );
return true;
}
void serialize( const Akonadi::Item& item, const QByteArray& label, QIODevice& data, int &version )
{
// we don't handle versions in this example
Q_UNUSED(version)
if ( label != Akonadi::Item::FullPayload || !item.hasPayload<PimNote>() )
return;
QDataStream stream( &data );
PimNote note = item.payload<PimNote>();
stream << note.author;
stream << note.dateTime;
stream << note.text;
}
};
Q_EXPORT_PLUGIN2( akonadi_serializer_pimnote, SerializerPluginPimNote )
The base class for item type serializer plugins.
virtual bool deserialize(Item &item, const QByteArray &label, QIODevice &data, int version)=0
Converts serialized item data provided in data into payload for item.
virtual void serialize(const Item &item, const QByteArray &label, QIODevice &data, int &version)=0
Convert the payload object provided in item into its serialzed form into data.
Represents a PIM item stored in Akonadi storage.
Definition item.h:100
void setPayload(const T &p)
Sets the payload object of this PIM item.
Definition item.h:905
bool hasPayload() const
Returns whether the item has a payload object.
T payload() const
Returns the payload object of this PIM item.
Definition item.h:754
static const char FullPayload[]
Describes the part name that is used to fetch the full payload of an item.
Definition item.h:126
Q_INTERFACES(...)
Q_OBJECTQ_OBJECT

The desktop file:

[Misc]
Name=Pim Note Serializer
Comment=An Akonadi serializer plugin for note objects
[Plugin]
Type=application/x-pimnote
X-KDE-Library=akonadi_serializer_pimnote
Helper integration between Akonadi and Qt.
Author
Till Adam adam@.nosp@m.kde..nosp@m.org, Volker Krause vkrau.nosp@m.se@k.nosp@m.de.or.nosp@m.g

Definition at line 105 of file itemserializerplugin.h.

Constructor & Destructor Documentation

◆ ~ItemSerializerPlugin()

ItemSerializerPlugin::~ItemSerializerPlugin ( )
virtualdefault

Destroys the item serializer plugin.

Member Function Documentation

◆ allowedForeignParts()

QSet< QByteArray > ItemSerializerPlugin::allowedForeignParts ( const Item & item) const
virtual

Returns the parts available in the item item that can be stored using foreign payload mechanism.

Is only called for items whose payload has been set via Item::setPayloadPath().

By default returns "RFC822", which can always be stored as foreign payload. Some implementations can also allow "HEAD" to be stored as foreign payload, if HEAD is only a subset of RFC822 part.

Since
5.7

Definition at line 58 of file itemserializerplugin.cpp.

◆ apply()

void ItemSerializerPlugin::apply ( Item & item,
const Item & other )
virtual

Merges the payload parts in other into item.

The default implementation is slow as it requires serializing other, and deserializing item multiple times. Reimplementing this is recommended if your type uses payload parts.

Parameters
itemreceives merged parts from other
otherthe paylod parts to merge into item
Since
4.4

Definition at line 40 of file itemserializerplugin.cpp.

◆ availableParts()

QSet< QByteArray > ItemSerializerPlugin::availableParts ( const Item & item) const
virtual

Returns the parts available in the item item.

This should be reimplemented to return available parts.

The default implementation returns an empty set if the item has a payload, and a set containing Item::FullPayload if the item has no payload.

Parameters
itemthe item for which to list payload parts
Since
4.4

Definition at line 31 of file itemserializerplugin.cpp.

◆ deserialize()

virtual bool Akonadi::ItemSerializerPlugin::deserialize ( Item & item,
const QByteArray & label,
QIODevice & data,
int version )
pure virtual

Converts serialized item data provided in data into payload for item.

Parameters
itemThe item to which the payload should be added. It is guaranteed to have a mime type matching one of the supported mime types of this plugin. However it might contain a unsuited payload added manually by the application developer. Verifying the payload type in case a payload is already available is recommended therefore.
labelThe part identifier of the part to deserialize. label might be an unsupported item part, return false if this is the case.
dataA QIODevice providing access to the serialized data. The QIODevice is opened in read-only mode and positioned at the beginning. The QIODevice is guaranteed to be valid.
versionThe version of the data format as set by the user in serialize() or 0 (default).
Returns
false if the specified part is not supported by this plugin, true if the part could be de-serialized successfully.

◆ overridePluginLookup()

void ItemSerializerPlugin::overridePluginLookup ( QObject * plugin)
static

Override the plugin-lookup with plugin.

After calling this each lookup will always return plugin. This is useful to inject a special plugin for testing purposes. To reset the plugin, set to 0.

Since
4.12

Definition at line 26 of file itemserializerplugin.cpp.

◆ parts()

QSet< QByteArray > ItemSerializerPlugin::parts ( const Item & item) const
virtual

Returns a list of available parts for the given item payload.

The default implementation returns Item::FullPayload if a payload is set.

Parameters
itemThe item.

Definition at line 17 of file itemserializerplugin.cpp.

◆ serialize()

virtual void Akonadi::ItemSerializerPlugin::serialize ( const Item & item,
const QByteArray & label,
QIODevice & data,
int & version )
pure virtual

Convert the payload object provided in item into its serialzed form into data.

Parameters
itemThe item which contains the payload. It is guaranteed to have a mimetype matching one of the supported mimetypes of this plugin as well as the existence of a payload object. However it might contain an unsupported payload added manually by the application developer. Verifying the payload type is recommended therefore.
labelThe part identifier of the part to serialize. label will be one of the item parts returned by parts().
dataThe QIODevice where the serialized data should be written to. The QIODevice is opened in write-only mode and positioned at the beginning. The QIODevice is guaranteed to be valid.
versionThe version of the data format. Can be set by the user to handle different versions.

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