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Maemo Feeds Ontology (MFO)

Maemo Feeds Ontology (MFO) — Model for feeds and alike online streams

Synopsis

@prefix mfo: <http://tracker.api.gnome.org/ontology/v3/mfo#>

Classes

Action, Enclosure, FeedChannel, FeedElement, FeedMessage, FeedSettings, FeedType

Overview

Introduction

This ontology is an abstract representation of entries coming from feeds. These feeds can be blogs (any of the common syndication formats can be translated into this representation), podcasts or even some online services (like flickr).

The basic assumption in the ontology is that all these feeds are unidirectional conversations with (from) the author of the content and every post on those channels is a message.

The source of the posts, the feed itself, is an instance of mfo:FeedChannel. Each post in that feed will be an instance of mfo:FeedMessage . The relation between the messages and the channel comes from their superclasses, nmo:communicationChannel (taking into account that mfo:FeedChannel is a subclass of nmo:CommunicationChannel and mfo:FeedMessage a subclass of nmo:Message).

A post can be plain text but can contain also more things like links, videos or Mp3. We represent those internal pieces in instances of mfo:Enclosure. This class has properties to link with the remote and local representation of the resource (in case the content has been downloaded).

Finally, the three important classes (mfo:FeedChannel, mfo:FeedMessage, mfo:Enclosure) are subclasses of mfo:FeedElement, just an abstract class to share the link with mfo:FeedSettings. mfo:FeedSettings contains some common configuration options. Not all of them applies to all, but it is a quite cleaner solution. For instance the mfo:maxSize property only makes sense per-enclosure, while the mfo:updateInterval is useful for the channel.

Special remarks

In some feeds, like "Yahoo Media RSS, there can be multiple enclosures together in a group, representing the same resource in different formats, qualities, resolutions, etc. Until further notify, the group will be represented using nie:identifier property . To mark the default enclosure of the group, there is a mfo-groupDefault property

Class Details

Action

Description

class with a restricted set of actions

Class hierarchy

    rdfs:Resource 
        mfo:Action 

Predefined instances

mfo:Action has the following predefined instances:

  • mfo:refresh-now


Enclosure

Description

Represents an enclosure of a feed message

Notify iconThis class emits notifications about changes, and can be monitored using TrackerNotifier.

Properties

Name Type Notes Description

groupDefault

boolean  

Different enclosures can represent the same resource in different formats/resolutions. This representations are grouped using the nie:identifier property and this property identify the default between them.

localLink

FileDataObject  

Downloaded copy of the enclosure

optional

boolean  

The enclosure is mandatory to download or only optional

remoteLink

RemoteDataObject  

Used to store remote URL of enclosure


FeedChannel

Description

Represents feed channel transfer, typically a download of RSS or ATOM.

Notify iconThis class emits notifications about changes, and can be monitored using TrackerNotifier.

Properties

Name Type Notes Description

action

Action  

Captures the current action for the channel: Refresh Now

totalCount

integer  

Total messages count within a channel

type

FeedType  

Feeds format type which is mapped to plugin used in engine: flickr,rss-atom

unreadCount

integer  

Unread messages count within a channel

updatedTime

dateTime  

Captures the updated date and time when the channel is updated


FeedElement

Description

Superclass for all elements related with feeds, to provide common configuration options

Properties

Name Type Notes Description

feedSettings

FeedSettings  

Settings

image

string    

FeedMessage

Description

Represents feed entry. May have enclosures attached and certain settings that allow deviation from feed channel's setup

Notify iconThis class emits notifications about changes, and can be monitored using TrackerNotifier.

Properties

Name Type Notes Description

downloadedTime

dateTime  

Captures the time stamp when message was downloaded

enclosureList

Enclosure This property can have multiple values.

A list of enclosures


FeedSettings

Description

Represents settings applied to a feed channel or a feed entry. How often it is updated, through which connection type it is delivered, when data expires and so on

Properties

Name Type Notes Description

downloadFlag

boolean  

To indicate whether enclosures will be downloaded or not

downloadPath

string  

Download path for enclosures in a message

expiryInterval

integer  

Expiry interval for feed channel, it tells time that a message in a channel can live. Interpreted as minutes

maxSize

integer  

Maximum size of enclosure that can be downloaded. Interpreted as KBs

updateInterval

integer  

Update interval for a feed channel to get updated or refreshed. Interpreted as minutes


FeedType

Description

class with a restricted set of feed types

Class hierarchy

    rdfs:Resource 
        mfo:FeedType 

Properties

Name Type Notes Description

name

string  

Feed format name like rss-atom,flickr,facebook

Credits and Copyright

Authors:
  • Jitendra Kumar <jitendra.1.kumar@nokia.com>
  • Ivan Frade <ivan.frade@nokia.com>
Editors:
  • Ivan Frade <ivan.frade@nokia.com>
Upstream:

Not available

ChangeLog:

Tracker changes