Viz Ticker User Guide
Version 4.0 | Published June 29, 2021 ©
Technical Reference for Field Linking
This section contains information on the following topics:
Feed Linking Formats
Viz Ticker supports Atom 1.0 formatted feeds.
The feed browser supports two types of feeds:
-
Flat feeds.
-
Hierarchical feeds (folder structure).
Linking to Social Media Sources
Some of the most popular web feeds, such as Twitter and Facebook, output content in non-supported formats or they use proprietary APIs. In order to get these and other Social feeds working together with Viz Ticker, the Ticker System must be combined with Vizrt’s Social TV solution (Feed Streamer). The Social TV solution then captures content from the social feeds and pushes moderated content to Viz Ticker wrapped in an open standard based network container format (example: Atom/XML) that can be combined with Ticker.
XML Namespaces
The following XML Namespace Prefixes are used when referring to XML elements:
XML Namespace Prefixes
Prefix |
URL |
atom |
|
viz |
|
vaext |
|
media |
|
thr |
|
opensearch |
Example: The notation <atom:entry> is to be interpreted as referring to the same element as <entry xmlns=”http://www.w3.org/2005/Atom”>.
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.
Elements in Atom Feed
Elements that should be present in the <atom:feed> for the full user experience:
OpenSearch Link
<atom:link rel=
"search"
type=
"application/opensearchdescription+xml"
href=
"http://example.com/opensearchdescription.xml"
/>
-
Optional, needed for support for server side searching.
-
The opensearchdescription XML file must contain a template node that returns search results as an atom feed:
<opensearch:Url type=
"application/atom+xml"
template=
"http://..."
/>
-
For more details see http://www.opensearch.org/Specifications/OpenSearch/1.1
Up Link
<atom:link rel=
"up"
type=
"application/atom+xml;type=feed"
href=
"http://..."
/>
-
Optional, needed for nested collections.
-
The up link should link to the parent folder feed for hierarchical feeds.
-
The up link must have a type string equal to "application/atom+xml;type=feed".
Elements in Atom Entry
Elements that should be present in the <atom:entry> for the full user experience:
Self Link
<atom:link rel=
"self"
type=
"application/atom+xml;type=entry"
href=
"http://..."
/>
-
The self link must link to the URL that returns the <atom:entry> XML.
-
The self link must have a type value equal to "application/atom+xml;type=entry".
-
Needed for refresh/update of values from the item to work.
-
Needed in combination with the up link for remembering and showing the selected feed entry in a hierarchy of feeds (folder structure). Not needed for remembering selection in flat feeds since then the atom:id is used.
-
Up Link
<atom:link rel=
"up"
type=
"application/atom+xml;type=feed"
href=
"http://..."
/>
-
The up link must have a HREF value that is the URL of the feed the entry is in.
-
The up link must have a type value equal to "application/atom+xml;type=feed".
-
Needed in combination with the self link for remembering and showing the selected feed entry in a folder structure.
-
Down Link
<atom:link rel=
"down"
type=
"application/atom+xml;type=feed"
href=
"http://..."
/>
-
Needed if this <atom:entry> is to be considered a subfolder instead of a normal <atom:entry>.
-
The down link must have a type value equal to "application/atom+xml;type=feed".
-
The down link must have a HREF value that is the URL of the feed (folder) the entry represents.
-
Link may contain thr:count attribute (RFC4685) indicating how many children there are. If the value of thr:count is 0 (zero) then the folder is not loaded since it is empty. This is an optimization.
-
Thumbnail Link
<media:thumbnail url=
"http://..."
/>
-
Needed for thumbnail icons to display on the entries in the feed browser.
-
The URL value must reference a JPEG or PNG image resource.
-
If many thumbnails are defined, the first one is selected as the default. This is according to Media RSS Specification Version 1.5.0.
-
Other Links
<link rel=
"..."
href=
"http://..."
type=
"..."
/>
-
Needed in order to select the URL to external resources. This can be images, video, text, and so on.
-
Limitation 1: The Atom 1.0 specs allow multiple links with the same relation, but when linking a tabfield to a link in Viz Ticker, only the first link is selected.
-
Limitation 2: Viz Ticker can only use the href URL as the value. It cannot download the resource at the URL and use its contents as the value. The Viz Engine control plug-in for the property has to be able to understand the URL and download the resource.
-
Fields that can be Linked
Field |
Details |
<atom:author> |
The personal details of the author of the selected <atom:entry>, which might be an individual person or an organization. The data is provided in child elements as follows:
|
<atom:content> |
|
<atom:entry> |
The whole entry XML. |
<atom:link> |
This element defines a reference from an entry to a Web resource; in other words this is the value of the href attribute. |
<vaext:locator> |
The text of the Vizrt Atom Extension <vaext:locator> element which has a vaext:type attribute equal to the "mediatype" attribute of <viz:fielddef> element in the model. |
<atom:published> |
This element is a Date construct indicating the initial creation or first availability of the entry. The value of the <atom:published> element in the entry is recorded as the field value. |
<atom:summary> |
This element is a Text construct that conveys a short summary, abstract, or excerpt of an entry. The content of the <atom:summary> element in the entry is recorded as the field value. |
<atom:thumbnail> |
The value of the URL attribute of the first thumbnail element in the entry is recorded as the field value. |
<atom:title> |
This element is a Text construct that conveys a human readable title for an entry or feed; the title of the selected <atom:entry>. |
<atom:updated> |
This element is a Date construct indicating the most recent instant in time when the selected <atom:entry> was modified. The value of the <atom:updated> element in the entry is recorded as the field value. |
Fields that cannot be Linked
-
<atom:category>
-
<atom:id>
-
<atom:rights>
-
Any other elements.
See Also