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    [[Image:Nepomuk_logo_big.png|center|300px]]
    [[Image:Nepomuk_logo_big.png|center|300px]]


    == About Nepomuk ==
    == About Nepomuk == <!--T:2-->


    This page is dedicated to Nepomuk development ideas, progress, experiments, and is a general starting point for new developers.
    <!--T:3-->
    '''Nepomuk''' serves as a cross application semantic storage backend. It aims at collecting data from various sources - file indexing, the web, applications, etc, and linking them all together to form a cohesive map of data.


    For general information about the Nepomuk project see the [http://nepomuk.kde.org/ dedicated Nepomuk homepage].
    <!--T:4-->
    This page is dedicated to third party documentation for '''Nepomuk'''. To know more about '''Nepomuk''' from a user's point of view, head over to the [http://userbase.kde.org/Special:myLanguage/Nepomuk Nepomuk page on UserBase]. Or to know more about the Nepomuk community and getting involved in '''Nepomuk''', head over to the [http://community.kde.org/Projects/Nepomuk Nepomuk Community Page].


    == Documentation == <!--T:5-->


    == Contact ==
    <!--T:6-->
    Any new project is intimidating and jumping right into the [http://api.kde.org/4.x-api/kdelibs-apidocs/nepomuk-core/html/index.html API Documentation] can be scary. So, we have prepared some articles which explain the different aspects of '''Nepomuk''' and even touch on some advanced features.


    '''IRC:''' #nepomuk-kde on Freenode
    <!--T:7-->
    The documentation of any project is always in progress as the code base is always evolving. If you feel that the documentation is lacking in some regard, please come talk to us. We'd love to hear your feedback, and the documentation might just get improved in the process.


    '''Mailing List:''' [https://mail.kde.org/mailman/listinfo/nepomuk nepomuk@kde.org]
    <!--T:8-->
    '''Nepomuk Mailing List: ''' nepomuk@kde.org <br/>
    '''IRC Channel:''' #nepomuk-kde on freenode


    '''Maintainer:''' [mailto:[email protected] Sebastian Trueg]
    === Introductory Material === <!--T:9-->


    '''Developers:''' [mailto:handa.vish@gmail.com Vishesh Handa]
    <!--T:10-->
    If you're just getting started with '''Nepomuk''' and want to know a quick way to fetch some data.


    == Documentation ==
    <!--T:11-->
    The [http://userbase.kde.org/Nepomuk Nepomuk page on UserBase] has information and troubleshooting for users.
    * [[Special:myLanguage/Projects/Nepomuk/QuickStart| Quick Start]]
    * [[Special:myLanguage/Projects/Nepomuk/OntologyBasics| Basic Ontology concepts]]
    * [[Special:myLanguage/Projects/Nepomuk/Uris| Questions about URIs]]


    The following links provide good reads for getting used to the Nepomuk system and its APIs.
    === Managing Data === <!--T:12-->
    * [[Development/Tutorials/Metadata/Nepomuk|Development Tutorials]]
    *'''[[Development/Tutorials/Metadata/Nepomuk/TipsAndTricks|Nepomuk Tips and Tricks]]'''
    * [http://api.kde.org/4.x-api/kdelibs-apidocs/nepomuk/html/index.html Nepomuk API Documentation]
    * [http://soprano.sourceforge.net/apidox/trunk/index.html Soprano (RDF storage) API]
    * [http://trueg.wordpress.com/2009/06/02/nepomuk-and-some-cmake-magic/ Using the Nepomuk Resource Code generator and the Soprano Ontology class generator in cmake]


    <!--T:13-->
    This section includes more in-depth articles on how manage the data in '''Nepomuk'''. As a starting point you should probably open up the [http://api.kde.org/4.x-api/kdelibs-apidocs/nepomuk-core/html/index.html Nepomuk API Documentation]. It is generally more up to date than the articles mentioned below.


    As Nepomuk is highly dependent on its data in the RDF store and the used ontologies, one might consider to read up on RDF and the Nepomuk ontogies:
    <!--T:14-->
    * [http://www.w3.org/TR/REC-rdf-syntax/ RDF Primer]
    * [[Special:myLanguage/Projects/Nepomuk/Resources| Using Resources]]
    * [http://www.semanticdesktop.org/ontologies Nepomuk Ontologies]
    * [[Special:myLanguage/Projects/Nepomuk/ResourceWatcher| Monitoring Changes]]
    * [http://dev.nepomuk.semanticdesktop.org/wiki/OntologyMaintenance Experimental Nepomuk Ontologies and Ideas for new ones]
    * [[Special:myLanguage/Projects/Nepomuk/BulkChanges| Bulk Changes]]
    * [[Special:myLanguage/Projects/Nepomuk/DataFeeders| Data Feeders]]


    == Events ==
    === File Indexing === <!--T:15-->


    [[Projects/Nepomuk/CodingSprint2009|June 19-21, 2009 - Coding Sprint 2009 Freiburg, Germany]]
    <!--T:16-->
    With 4.10, the file indexing architecture has substantially changed. We no longer rely on strigi, and have our own plugin based interface.


    [[Projects/Nepomuk/OpenSocialSemanticDesktopWorkshop2009|Open Social Semantic Desktop Workshop 2009 Freiburg, Germany]]
    <!--T:17-->
    * [[Special:myLanguage/Projects/Nepomuk/IndexingPlugin| Writing an Indexing Plugin]]


    == ToDo  ==
    === Querying === <!--T:18-->


    Nepomuk is a rather young project with a notorious shortage in developers. There are many tasks and subprojects to get ones hands dirty on. Unlike other projects like Plasma, however, developing for Nepomuk is not easy. One has to read up on a lot of things and fight some day-to-day annoyances. But: helping with the development will improve the situation in any case.  
    <!--T:19-->
    As you advance into '''Nepomuk''', you'll want to move beyond just fetching and pushing data and will want to query '''Nepomuk''' for specialized data. One can query '''Nepomuk''' in many different ways, the important part is to optimize your queries and make sure they run well on production systems where the database sizes may way very large.


    If you are interested in working on a task in this list, please contact [mailto:[email protected] Sebastian Trueg].
    <!--T:20-->
    * [[Special:myLanguage/Projects/Nepomuk/QueryingMethods| Different ways to Query Nepomuk]]
    * [[Special:myLanguage/Projects/Nepomuk/QueryLibrary| Nepomuk Query Library]]
    * [[Special:myLanguage/Projects/Nepomuk/SparqlQueries| Sparql Queries]]


    === Junior Jobs ===
    === Architectural Overview === <!--T:21-->
    If you want to get into Nepomuk development quickly by taking over a small task have a look at our [[Projects/Nepomuk/JuniorJobs|Junior Job page]].


    === Low level Nepomuk Development Tasks  ===
    <!--T:22-->
    If you're looking to get more involved with '''Nepomuk''' development process, you should probably need to need to figure out our basic architecture and where you can find all the relevant code.


    The low-level development tasks are those that are not directly reflected in the GUI or even in the API used by most developers. However, they are important in terms of performance, scalability, and compatibility.
    <!--T:23-->
    * [[Special:myLanguage/Projects/Nepomuk/Repositories| Nepomuk Repositories]]
    * [[Special:myLanguage/Projects/Nepomuk/ComponentOverview| Nepomuk Architectural Overview]]
    * [[Special:myLanguage/Projects/Nepomuk/kioslaves| Nepomuk KIO Slaves]]


    === Nepomuk Internals === <!--T:24-->


    ==== Add Inference Configuration to the Virtuoso Soprano Backend ====
    <!--T:25-->
    When you decide to dig even deeper.


    Virtuoso 5 provides inference on rdfs:subClassOf and rdfs:subPropertyOf. These are the most important ones and for now all we need in Nepomuk.
    <!--T:26-->
    * [[Special:myLanguage/Projects/Nepomuk/GraphConcepts| Graph handling]]
    * [[Special:myLanguage/Projects/Nepomuk/VirtuosoInternal| Virtuoso Internals]]
    * [[Special:myLanguage/Projects/Nepomuk/OntologyExtention| Extending the Ontologies]]


    The current implementation of the Virtuoso Soprano backend does not enable inference. We need a configuration option to do exactly that. It could happen along the lines of the [http://soprano.sourceforge.net/apidox/trunk/soprano_backend_virtuoso.html existing config options] or with the introduction of dedicated inference configuration options on the Soprano::Backend level.
    === Miscellaneous === <!--T:27-->


    <!--T:28-->
    * [[Special:myLanguage/Projects/Nepomuk/Nepomuk2Port| Porting to Nepomuk2]]
    * [[Special:myLanguage/Projects/Nepomuk/ManagingNepomukProcesses| Managing Nepomuk Processes]]
    * [[Special:myLanguage/Projects/Nepomuk/TestEnvironment| Nepomuk Test Environment]]
    * [[Special:myLanguage/Development/Tutorials/Metadata/Nepomuk/TipsAndTricks| Nepomuk Tips and Tricks]]
    * [[Special:myLanguage/Projects/Nepomuk/NepomukShow| Debugging Nepomuk Data]]


    ==== Outdated links ==== <!--T:29-->


    <!--T:30-->
    The following links provide good reads for getting used to the '''Nepomuk''' system and its APIs. <br\>
    They are slightly outdated, but still has some useful material.
    * [[Special:myLanguage/Development/Tutorials/Metadata/Nepomuk|Development Tutorials]]
    * [[Special:myLanguage/Projects/Nepomuk/Ideas|Random Ideas]]
    * [[Special:myLanguage/Projects/Nepomuk/Qualified_Relations_Idea| Qualified Relations Idea]]
    * [[Special:myLanguage/Projects/Nepomuk/ScenarioExamples| Scenario Examples]]


    ==== Soprano Transaction Support  ====
    <!--T:31-->
     
    [[Category:Documentation]]
    [http://soprano.sf.net/ Soprano] is the RDF database framework used in Nepomuk. Currently Soprano does not support transactions, i.e. sets of commands that can be rolled back. An [http://websvn.kde.org/branches/soprano/experimental experimental development] branch exists which already contains new API for transaction support (while keeping BC).
    </translate>
     
    It still misses an implementation of the transaction support in Soprano backends (Sesame2 and Virtuoso) and in the client/server architecture.
     
    Another idea is to create a new API based on the design that Sesame2 follows: Repository and RepositoryConnection classes. The former creates instances of the latter which then has all the actual data handling methods and acts as one transaction object.
     
     
    === General Nepomuk  ===
     
    ==== Nepomuk Toolbox ====
    Provide a GUI that allows to call methods such as ''optimize'' and ''rebuildIndex'' on the storage service. The latter method is not commited yet due to the KDE 4.3 feature freeze but will be afterwards.
     
    It would also be useful to have Nepomuk register such operations (including the data conversion when changing backends) via the notification system.
     
    == Development status ==
     
    See [[Projects/Nepomuk/DevelopmentStatus]].
     
    http://techbase.kde.org/Projects/Nepomuk/Ideas
     
    == Subpages of {{FULLPAGENAME}}==
    {{Special:PrefixIndex/{{FULLPAGENAME}}/}}

    Revision as of 17:07, 10 December 2012


    About Nepomuk

    Nepomuk serves as a cross application semantic storage backend. It aims at collecting data from various sources - file indexing, the web, applications, etc, and linking them all together to form a cohesive map of data.

    This page is dedicated to third party documentation for Nepomuk. To know more about Nepomuk from a user's point of view, head over to the Nepomuk page on UserBase. Or to know more about the Nepomuk community and getting involved in Nepomuk, head over to the Nepomuk Community Page.

    Documentation

    Any new project is intimidating and jumping right into the API Documentation can be scary. So, we have prepared some articles which explain the different aspects of Nepomuk and even touch on some advanced features.

    The documentation of any project is always in progress as the code base is always evolving. If you feel that the documentation is lacking in some regard, please come talk to us. We'd love to hear your feedback, and the documentation might just get improved in the process.

    Nepomuk Mailing List: [email protected]
    IRC Channel: #nepomuk-kde on freenode

    Introductory Material

    If you're just getting started with Nepomuk and want to know a quick way to fetch some data.

    Managing Data

    This section includes more in-depth articles on how manage the data in Nepomuk. As a starting point you should probably open up the Nepomuk API Documentation. It is generally more up to date than the articles mentioned below.

    File Indexing

    With 4.10, the file indexing architecture has substantially changed. We no longer rely on strigi, and have our own plugin based interface.

    Querying

    As you advance into Nepomuk, you'll want to move beyond just fetching and pushing data and will want to query Nepomuk for specialized data. One can query Nepomuk in many different ways, the important part is to optimize your queries and make sure they run well on production systems where the database sizes may way very large.

    Architectural Overview

    If you're looking to get more involved with Nepomuk development process, you should probably need to need to figure out our basic architecture and where you can find all the relevant code.

    Nepomuk Internals

    When you decide to dig even deeper.

    Miscellaneous

    Outdated links

    The following links provide good reads for getting used to the Nepomuk system and its APIs. <br\> They are slightly outdated, but still has some useful material.