Difference between revisions of "KDE PIM/Akonadi"

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=== Do I need a running MySQL server? ===
=== Do I need a running MySQL server? ===
No. Akonadi starts it's own local MySQL server. All you need is having the 'mysqld' binary installed (usually found in the mysql-server package of your distribution).
No. Akonadi starts it's own local MySQL server. All you need is having the 'mysqld' binary installed at runtime (usually found in the mysql-server package of your distribution).
=== Can Akonadi use a normal MySQL server running on my system? ===
=== Can Akonadi use a normal MySQL server running on my system? ===

Revision as of 22:12, 23 April 2008

Akonadi TODO

The following list contains the things which need to be done for Akonadi.

Note: The person noted in the "Contact" column is not necessarily the one implementing that feature, but the one who can tell you what to do and how to help, i.e. you can also contribute to those tasks ;-)


Urgent tasks that need to be finished for the KDE 4.1 release (May 19th):

Status Item Description Contact
IN PROGRESS Item size Needed by Mailody <[email protected]>
TO DO Payload serialization format versioning see below <Volker>
IN PROGRESS Item streaming in ItemSync/ResourceBase As discussed in Osnabrueck <Tom>
DONE API for additional item parts As discussed in Osnabruck <Volker/Tobias>
DONE Infrastructure for showing additional dialogs from agents/resources As discussed in Osnabrueck <Tom>
IN PROGRESS Allow to limit ItemFetchJob to current cache content Prevents search index feeder agents from downloading all remote data Volker <[email protected]>
DONE Fix API for item/collection modifications See Osnabrueck meeting notes for details Volker <[email protected]>
TO DO Error reporting Akonadi::Job basically has only one error code: Unknown <Tobias>
TO DO Plugin Versioning For serializer plugins, also check using Qt plugin stuff instead of the libkdepim plugin framework [mailto: <>]

Less urgent tasks

Status Item Description Contact
DONE Tray app small app to control the server and have a something that can report errors Toma <[email protected]>
IN PROGRESS Akonadi Artwork Icon for the tray app Toma <[email protected]>
IN PROGRESS Finish collection model/view see below <[email protected]>
DONE Backup support Dump & Restore database contents, also useful when upgrading to a newer database version <[email protected]>
IN PROGRESS Collection statistics for sub-trees Provide a CollectionStatus object covering the full sub-tree in the model, allowing accumulated unread counts etc. <Thomas>
TO DO Nepomuk integration Generic Item tag/rate/comment, etc. <Tom>
TO DO Account creation wizard as discussed in Berlin, see below [mailto: <>]
TO DO Sync collection tree after creating setting up a resource see AgentInstanceCreateJob [mailto: <>]
TO DO Support standard commands for QUndo framework [mailto: <>]
TO DO Conflict detection in resources See Osnabrueck meeting notes for details [mailto: <>]
IN PROGRESS Action framework see below Volker <[email protected]>
TO DO Solid integration Switch online/offline state in ResourceBase automatically [mailto: <>]
TO DO Make unittests work without destroying the production database [mailto: <>]
TO DO Fix API docs The libakonadi move as well as the huge API changes following it broke lots of the docs technical and content-wise [mailto: <>]

Supported Types

Overview on the current state of support for various types:

Type Serializer Multipart Support Models Views Resources Notes
Email yes partial MessageModel, MessageCollectionModel, threading proxy model ? maildir, IMAP threading agent
News yes (1) partial (1) (1) (1) NNTP
Contact yes no ContactModel - vCard, facebook, KRes
Events yes no EventModel - iCal, KRes
Notes no no - - - not started yet
Feeds no no - - - not started yet
Bookmarks yes no - - local bookmarks, del.icio.us

(1) see Email

Mail specific extensions

Status Item Description Contact
TO DO Extend Message Model Add all required columns, save/restore layout, flag delegate, configurable columns, etc. [mailto: <>]
TO DO Share mail flag code Standard actions, standard flag enum/constants, Nepomuk interaction [mailto: <>]
TO DO Extend ENVELOPE Add more information to the envelope payload part in the serializer plugin, eg. trheading information is missing [mailto: <>]
TO DO Fix/finish threading [mailto: <>]

Event/Todo/Journal specific extensions

Status Item Description Contact
TO DO Todo proxy model See KOrganizers To-Do view <Bruno?>
IN PROGRESS Subtype identification See discussion on kde-pim mailinglist <Kevin?>
TO DO Agenda view KOrganizer agenda view based on Akonadi <Bruno?>
TO DO Month view KOrganizer month view based on Akonadi <Bruno?>
TO DO Timeline view KOrganizer timeline view based on Akonadi [mailto: <>]

Resources, Agents and others

Status Item Description Contact
IN PROGRESS KResource Akonadi bridge for applications using KCal or KABC Kevin <[email protected]>
IN PROGRESS Akonadi KResource bridge for data accessed through KCal or KABC resources Kevin <[email protected]>
TO DO Expire Agent [mailto: <>]
TO DO MBOX Resource <Thomas>
TO DO Extend IMAP Resource [mailto: <>]
TO DO POP3 Resource <Thomas>
TO DO RSS Resource [mailto: <>]
TO DO Filter Agent [mailto: <>]
TO DO Search [mailto: <>]
TO DO Filter Rule GUI Used by filters and searches [mailto: <>]

Resource status overview (this should list all resources existing in KDE3 or already under development for Akonadi):

Resource Retrieve Collections Retrieve Items Change Collections Change Items Configuration Notes
iCal yes (4) yes (1) (2) no yes (5) yes does not yet watch for file changes
vCard yes (4) yes (1) (2) no ? yes does not yet watch for file changes
maildir yes (1) (4) yes (1) (2) ? ? yes
mbox no no no no no not started yet, code exists in KMail
IMAP yes (1) (4)? yes (1) (2) no no no code exists in kio_imap4 and Mailody, support for extensions: quota, ACL, annotations missing, what about Kolab and Scalix?
POP3 no no no no no not started yet,code exists in kio_pop3
NNTP yes (4) yes (2) n/a n/a yes Needs support for local collection names and collection hierarchy
Local Bookmarks ? ? ? ? (3) Code in akonadi/resources
OpenChange ? ? ? ? ? Code in akonadi/resources
Facebook ? ? ? ? ? Code in playground/pim
del.icio.us ? ? ? yes no Code in playground/pim
KABC no yes no yes yes
KCal no yes no yes yes

(1) only full sync supported currently, need optimization (2) does not yet honor cache policy (3) still relies on QSettings for configuration and/or doesn't provide configuration over D-Bus (4) does not yet provide correct access control settings (5) only adding new items, not changing existing ones

Akonadi Braindump

Ideas/notes etc. on various open issues in Akonadi.

Akonadi Standard Actions

Idea: Have something like KStandardAction for Akonadi that not only includes the representation of the action but also its state management and the actual operations. Like libakonadi that should be splitted into a generic, type-independent part and be extensible for type-specific actions. This will enable code sharing among many applications and guarantee consistent actions everywhere.

State management: watch selection models of a collection and/or item model.

Use KXMLGUI for context menus in standard views to allow easy extensibility with custom actions.

Generic actions:

  • new collection [done]
  • new virtual collection
  • delete collection [done for single selection]
  • copy collection [done]
  • cut collection
  • paste collection [done]
  • synchronize collection [done for single selection]
  • synchronize resource
  • synchronize everything
  • show collection properties dialog [done]
  • delete item(s) [done]
  • copy item(s) [done]
  • cut item(s)
  • paste item(s) [done]
  • paste native data
  • tag item(s)
  • comment item
  • rate item(s)
  • configure resource
  • add resource? (would need a type parameter, etc.)
  • delete resource
  • manage local subscriptions [done]
  • move to submenu
  • copy to submenu

The list is definitely long enough to make this worthwhile.

Collection Model / Collection View

Ideas/missing features/bugs of the collection model/view:

  • Enable/disable status columns
  • Show status after the name (see KMail)
  • Size column
  • Save/restore layout
  • Custom collection icons (see KMail, also needed for resource defined special folders (eg. Inbox)
  • Status tooltips (see KMail in 3.5.9)
  • Quick search
  • Favorite folder view as proxy model on top of the normal collection model (FlatCollectionProxyModel might be helpful for there)
  • Accumulated statistics (unread, total, size)
  • Fix dnd: move/copy/cancel menu always shows up and never has any effect


Notes on how to keep long-term protocol, source and binary compatibility.

  • Detect server version in Akonadi::Session, might be useful in case of protocol extensions/changes
  • What about database server version updates?
  • Versioning or any other kind of serialization format meta data, we'll need that in case of changes in serialization formats (see eg. Robert's compression patch where this is needed)
  • We currently use 32 bit ids, probably hard to change later on, is that enough?
  • Plugin versioning

Resource API issues

Notes/ideas/complaints about the Akonadi::ResourceBase API:

  • Extremely error prone:
    • Scheduler dead-locks when a requested operation is not correctly announced as finished, esp. a problem in error cases.
    • Using the result methods multiple times or when not requested asserts
  • Item streaming is missing, requiring all data to be in memory at once
  • Non-incremental updates need to know the results of ItemSync to not have to provide all data, even for already existing/unchanged items.

API / BC issues

Smaller stuff that should be fixed before the ABI freeze and is not yet listed above:

  • Cleanup the D-Bus format used by NotificationMessage
  • No mentioning of "IMAP" in the public API, we are not using IMAP
  • Naming and installed location of libraries, headers and executables (see discussion on kde-pim ML)
  • Payload part labels are QStrings, attribute types are QByteArray

Deployment issues

  • Multiple access: Should multiple Akonadi instances' mysqlds access a single set of data files the mysql will likely corrupt the data. This can happen in any NFS+YP installation where users can log onto any machine and access shared homes. MySQL relies on filesystem locking to prevent multiple access. MySQL multiple instance docu.
  • InnoDB tables should not be used on NFS.
  • NFS speed: MySQL documentation recommends against locating its data files on network shares.
  • AppArmor: Distros' AppArmor profiles prevent MySQL from writing outside its defined data directory (usually /var/lib/mysql). This is a problem at least with *buntu and openSUSE. These will need to be adapted. It is possible to daisy-chain profiles so that MySQL started by Akonadi receives a different profile to MySQL running standalone. An empty profile has all rights. Another possibility is to adapt the general MySQL profile so it can write to ${XDG_DATA_HOME}/akonadi(usually ${HOME/}.local/share/akonadi). Both support for profile chaining and ${HOME} may depend on the version of AppArmor installed. What about SELinux?
  • Backup: MySQL data files should not be backed up without telling the mysqld process, otherwise a corrupt backup will be made. LOCK TABLES and FLUSH TABLES at the least. A dump can be made or mysqlhotbackup may be used in some circumstances. We should consider sysadmins' backup techniques when planning/promoting Akonadi, as a simple rsync cronjob with running Akonadi will not work. MySQL backup advice.

Account Creation Wizard

Notes on the resource configuration wizard discussion.

  • WizardBase class
  • Wizard discovery via .desktop files
  • A wizard can configure multiple resources (eg. IMAP + LDAP for Kolab) and non-resources (mailtransport)
  • Optionally hide resources completely covered by wizards in the Add Account dialog
  • List wizards in the Add Account dialog
  • Store Account -> Resources information to offer deletion of depending resources

PostgreSQL datastore support

First review of the akonadi code reveals PGSQL Qt driver is already supported, but the code is not totally ready for it. Some first reading comments about where to patch for supporting PostgreSQL too:


  • line 201..., ALTER TABLE ADD [UNIQUE] INDEX syntax is MySQL only, better use the common one CREATE [UNIQUE] INDEX ... one [done with revision 789899]
  • line 303, QString DbInitializer::sqlType(const QString & type), LONGBLOB is the MySQL type, PostgreSQL will use BYTEA.
  • line 362, qFatal("Implement index support for your database!");
 pgsql: SELECT c2.relname, i.indisprimary, i.indisunique, i.indisclustered, i.indisvalid, pg_catalog.pg_get_indexdef(i.indexrelid, 0, true), c2.reltablespace
 FROM pg_catalog.pg_class c, pg_catalog.pg_class c2, pg_catalog.pg_index i
 WHERE c.oid = '16713' AND c.oid = i.indrelid AND i.indexrelid = c2.oid
 ORDER BY i.indisprimary DESC, i.indisunique DESC, c2.relname
    relname    | indisprimary | indisunique | indisclustered | indisvalid |                       pg_get_indexdef                        | reltablespace
  foo_pkey     | t            | t           | f              | t          | CREATE UNIQUE INDEX foo_pkey ON foo USING btree (id)         |             0
  foo_time_key | f            | t           | f              | t          | CREATE UNIQUE INDEX foo_time_key ON foo USING btree ("time") |             0
 (2 lignes)


  • line 700, qint64 DataStore::highestPimItemId() const, seems wrong for a concurrent program (SELECT MAX(col) FROM table; is not reliable if another thread is inserting at the same time) : check the callers
  • line 794, qint64 DataStore::lastInsertId( const QSqlQuery & query ), PostgreSQL doesn't provide concurrent-bogus last_insert_id, but from 8.2 accepts the syntax INSERT INTO ... RETURNING col1, col2, ...;
  • line 806, QString DataStore::dateTimeFromQDateTime( const QDateTime & dateTime ), use PostgreSQL to_char() formatting function for date rather than having Qt do it

KMail Breakdown Plan

The current plan is to put some parts of KMail into a stand-alone library, independent of KMail. This increases code reuse (for example, the message composer could be shared with Mailody) and makes the code a lot easier to maintain and to port to Akonadi.

Status Item Description Contact
TO DO Bodypart formatters [mailto: <>]
TO DO Reader Window [mailto: <>]
TO DO Composer: Editor [mailto: <>]
TO DO Composer: Message Composer [mailto: <>]
TO DO Composer: GUI Window [mailto: <>]
TO DO Queue Manager for mailtransport [mailto: <>]
TO DO Templates: Core [mailto: <>]
TO DO Templates: GUI [mailto: <>]
TO DO Port KMCommands [mailto: <>]
TO DO Port away from KMMessage and KMFolder* everywhere it is left [mailto: <>]
TO DO Migration application for index and other config [mailto: <>]
TO DO Port MDNs [mailto: <>]

The Road to World Domination

Sort of related so the stuff above but with a scope for all of KDE PIM and beyond.

Status Item Description Contact
TO DO Share identity config GUI parts eg. the signature configuration widget [mailto: <>]
TO DO Mailtransport Agent Global shared outbox, central mail sending instance [mailto: <>]
TO DO Recently sent to support in mailtransport related to above, based on Akonadi/Nepomuk [mailto: <>]
TO DO Composer engine Shared stuff for KMail/KNode/Mailody: Crypto, editor, editor actions, attachment model, message assembly, etc. [mailto: <>]

Akonadi FAQ

Where do I find the Akonadi config files?


Where does Akonadi store my data?


Which DBMS does Akonadi use?

So far only MySQL. There is some work on PostgreSQL support going on though.

Why not use sqlite?

We tried. Really. It can't handle the concurrent access very well.

Why not use MySQL/Embedded?

We tried that as well, there are two reasons for not using it: No support for the InnoDB engine (which we need for transaction support) and poor availability (only OpenSUSE provided usable packages, needed a patched QSQL driver).

Do I need a running MySQL server?

No. Akonadi starts it's own local MySQL server. All you need is having the 'mysqld' binary installed at runtime (usually found in the mysql-server package of your distribution).

Can Akonadi use a normal MySQL server running on my system?

Yes, it can. You find the corresponding settings in ~/.config/akonadi/akonadiserverrc.

Can a single Akonadi instance be used by multiple users?

No. There has to be one Akonadi server instance per user. However, it is possible to use a shared database server.

Can I access the Akonadi server on a remote machine?

No. Akonadi is not a groupware server. It's a local cache only.

This page was last edited on 23 April 2008, at 22:12. Content is available under Creative Commons License SA 4.0 unless otherwise noted.