Akonadi

Einführung

Das Akonadi-Framework stellt eine zentrale Datenbank für unterschiedliche Anwendungen bereit, in der persönliche Informationen des Nutzers gespeichert, indiziert und wieder ausgelesen werden können. Das gilt für E-Mails, Kontakte, Kalender, Ereignisse, Tagebücher, Alarme, Notizen usw. Adressbuch war die erste Anwendung, die das Akonadi-Framework genutzt hat. In SC 4.7 kamen KMail, KOrganizer und KJots hinzu. Darüber hinaus nutzen mehrere Plasma-Widgets ebenfalls Akonadi für ihre Kalendereinträge, Notizen, etc.

Currently, all KDE PIM applications with the exception of Akregator are using Akonadi to access user's PIM data.

Steuern des Akonadi-Servers

Akonadi will start automatically in the background when any application using it is started.

To manually start, stop or restart Akonadi, you can use the akonadictl command from the commandline. Using this method, you can get additional useful information on the console.

Zum Starten des Akonadi-Servers

akonadictl start

Um den Akonadi-Server zu stoppen:

akonadictl stop

Um den Neustart eines laufenden Akonadi-Servers zu erzwingen:

akonadictl restart

Zur Abfrage des Akonadi-Serverstatus:

akonadictl status

Deaktivierung des Akonadi Subsystems

Der Akonadi Server wird von jeder Akonadi fähigen Anwendung gestartet. Wenn Sie nicht möchten, dass Akonadi nach der Anmeldung startet, müssen Sie sicherstellen, dass keine Akonadi fähigen Anwendungen bei- oder nach der Anmeldung gestartet werden. Denken Sie auch an Plasma widgets, wie z.B. die Digitaluhr

Remember

Wenn Sie gar nicht möchten, dass Akonadi auf Ihrem System läuft, können Sie keine der Akonadi-fähigen Anwendungen verwenden. Diese Anwendungen starten Akonadi, sobald sie dessen Dienste brauchen, auch wenn es deaktiviert wurde. Siehe Liste der Akonadi-fähigen Anwendungen. Beachten Sie auch, dass auch einige der Plasma-Widgets wie die Digitaluhr ebenfalls Akonadi verwenden

Um sicherzustellen, das Akonadi nicht gestartet wird prüfen Sie, ob keine Anwendungen den Server beim Anmelden aktivieren. Im Speziellen öffnen Sie die Einstellungen der Plasma-Minianwendung Digitale Uhr, wählen den Kalender und deaktivieren dort die Funktion Ereignisse anzeigen, um Plasma davon abzuhalten, Informationen von Akonadi anzufordern und es damit zu starten.

Some Definitions

Real data

By real data we mean the data, like the contacts or events. These data are stored either on a groupware server or in local files. Where exactly depends on the resource you are using. E.g. the Personal Contacts resource stores its data under $XDG_DATA_HOME/contacts.

Cached data

The cached data are copies of the real data that are kept in the database for faster access and offline caching. The database also keeps the meta data which are management data needed by Akonadi to work correctly.

Configuration data

The configuration data are the data that configure the Akonadi server and the individual resources. The general configuration data for the server can be found under $XDG_CONFIG_HOME/akonadi. The configuration data for each indvidual resources are stored under $XDG_CONFIG_HOME/akonadi_xyz_resourcerc# (xyz is name of resource and # its instance number).

The Akonadi server configuration is a couple of files in $XDG_CONFIG_HOME/akonadi. It contains which data sources and helper programs are active and will be started and watched (so they can be restarted on crashes) by one of Akonadi's server processes (akonadi_control).

Each data source handler (called resources) or helper program (called agents) can have its own configuration although some agents or resources don't require configuration. The general rule is that for every entry in $XDG_CONFIG_HOME/akonadi/agentsrc there is a corresponding configuration file in $XDG_CONFIG_HOME. For example, if the [Instances] section in agentrc contains an entry for akonadi_ical_resource_2, there is also a config file called akonadi_ical_resource_2rc in the $XDG_CONFIG_HOME directory.

Depending on the type of data, such config files for resources will have filenames or directory names of where the data is stored. Common locations are KDE's legacy default files, e.g. $HOME/.kde/share/apps/korganizer/std.ics. New default locations are files and directories in $XDG_DATA_HOME, e.g. $XDG_DATA_HOME/contacts.

Backup

So now we need to decide what to back up. If you want to backup the "real data", then it depends on the resources you have configured... if you use a groupware server, then the backup should be done there. For contacts, the files under $XDG_DATA_HOME/contacts will normally be what you need.

To back up the entire Akonadi configuration, including which resources are active and their configuration, you can use the pimdataexporter' tool. This, however doesn't back up the Akonadi database containing the cached data and, unfortunately, after restoring the configuration (using the pimdataexporter again), Akonadi will have to re-fetch all data again into its cache. This can cause configuration that points to actual mail folders or calendars to get broken and accidentally point to another folder.

After restoring configuration and syncing all data, it's vital to manually check all folder configuration, especially in KMail identities and make sure the folders are configured properly.

Fragen und Antworten (FAQ)

Wo sind meine Daten jetzt abgelegt?

Your data are safely stored outside of Akonadi control on your disk (e.g. local maildir folder or iCal calendar), or on a remote server (in case of e.g. email over IMAP or events from a CalDAV calendar). Akonadi will optionally store a copy of this data in its database to allow applications to quickly retrieve and display them. Any modifications done to data in the Akonadi database will be synced to the actual storage. The main advantage of using the database as a cache is that remote PIM data are available even when you are offline, and you can still interact with them (e.g. mark emails as read or move them, create new events, reschedule existing meetings etc.) and all the changes will get synced automatically once you connect to the internet again.

Thus, deleting the Akonadi database will not cause any data to be lost (as long as all pending changes are synced).

Wie führe ich eine Aktualisierung meiner PostgreSQL durch

Nach Aktualisierung ihrer PostgreSQL-Server auf eine neue Hauptversion ist es manchmal erforderlich die Akonadi-Datenbank zu konvertieren damit sie mit der neuern Version funktioniert. Anleitungen hierzu finden sich hier.

Umstiegs-Probleme

Akonadi's Glossar-Eintrag enthält eine Zusammenfassung und weitere nützliche Verknüpfungen. Auf der Seite Akonadi und das Adressbuch wird erklärt, wie Akonadi und KAddressBook zusammenarbeiten.

How do I switch from MySQL/PostgreSQL to SQLite?

Since Akonadi 6 akonadi-db-migrator is included in akonadi that allows you to switch the database backend. Where for previous versions this involved deleting and recreating the database a migration is now properly supported by akonadi.

The tool needs to be called with the parameter --newengine to chose to which backend it should to: {{{

 --newengine <ENGINE>       The new DB engine to use. Possible values are 
                            "sqlite", "mysql" and "postgres"

}}}

For example: {{{ akonadi-db-migrator --newengine sqlite }}}