Mashups and Microsoft SharePoint Part 2.1: Presto Consuming SharePoint Services

This is the sixth in a many-part series about Mashups and Microsoft SharePoint.  You can read about the entire series at http://www.jackbe.com/enterprise-mashup/blog/mashing-sharepoint-introduction.

This article will focus on how SharePoint generated RSS can be consumed by Presto, other articles will look at SharePoint Web Service consumption and how SharePoint Services can be mashed using Presto.

Here are links to the other articles:

• Mashing Sharepoint RSS Feeds with Presto Wires
• Sharepoint Web Services
  • Publishing a Sharepoint Web Service on Presto
  • Mashing Sharepoint Web Services

Really Simple Syndication RSS

SharePoint 2007 has extensive support for publishing data using RSS, enabling users to subscribe to SharePoint data services such as Blogs, Task Lists, Discussions, Document Lists, Link Lists and Search Results.

The RSS Feeds can be consumed internally within the SharePoint Environment, they can also be consumed externally, with access protected by NTLM Authentication by default.

Presto Enterprise Mashup Server version 2.6.1 or later is able to consume NTLM protected Services.

Enabling SharePoint RSS

The SharePoint Web Application Settings "RSS Settings" property must be enabled to allow users to subscribe to SharePoint List views in syndicated format. This option is enabled by default. The option can be checked via Central Administration, Web Application Management section, Web Application Settings.

Almost any list-based data service provided by SharePoint can be published in RSS form. The following are a selection of the SharePoint data services which can be RSS enabled:

1. Blogs
   

   SharePoint Site users can create and edit blog posts.

   Blog entries can be posted to both site and personal blogs.

   Access to blog posts can be controlled by setting user permissions.

   Access to blogs is restricted to authorized users.

   Users are able to subscribe to a blog RSS Feed.

   The Recent Blog Posts Data Form Web Part is able to display in summary form,

   recent blog posts for a given user to which the viewing users has access.

   Can this Web part be published as RSS?

2. Discussion Lists
   

   SharePoint Discussion lists are a useful source of information which can be published in RSS form and which Presto can consume.

   In RSS Form a SharePoint Discussion list is comprised of a set of discussion topics,

   with title and description and a NTLM Authenticated URL link back to the actual SharePoint Discussion page.

   A Discussion List might be mashed up with discussion topics gathered from sources external to SharePoint.

   Merged and filtered the discussion could then be consumed either by SharePoint or some external non-SharePoint user environment in the form of an RSS Feed or Mashlet.

3. Calendars
4. Task Lists
5. Announcement Lists
6. Issue Tracking Lists
7. Link Lists
8. Key Performance Indicators (KPI) List
   

   A KPI Web Part can be configured to view a KPI List.

   Key Performance Indicator lists a set of user defined indicators including target goal,

   current value and target status information.

9. Filter Web Part
   

   Filter Web Part enables the user to connect to multiple data sources and to dynamically

   collect and filter data.

10. Search Results

RSS Feed URL General form is :

http://host/Site/_layouts/listfeed.aspx?List=Guid

SharePoint Search Results

SharePoint Search Results can be made available as an RSS feed. This may be a suitable for the case where the user wishes to periodically check search results for a give set of fixed search criteria.

SharePoint provides various Web Parts through which the user is able to customize the Search criteria and Search Results.

Customization of Search Criteria enable us to control details of the search query and the scope of the search. Customization of the Search Results enable us to control the content and structure of the Search Result which, in turn, will alter the content of the Search Result RSS feed.

Customization may take the form of:

• search scope and query
• result paging
• handling of duplicate result entries
• grouping and collapsing of search results

The Search Actions Web Part must be configured to Display RSS, which can be performed by:

1. Selecting Edit Page in the Site Actions menu.
2. Edit the Search Actions Link Web part.
3. Select Modify Shared Web Part.
4. Ensure the Display RSS Link checkbox is selected in the Search Results Action Links list.

See Overview of SharePoint 2007 Search capabilities

Having retrieved a set fo search results, displayed in a search result list view, the search results can be viewed in RSS format by selecting "View RSS Feed" from the List Actions menus. SharePoint will redirect to a URL for the Search Results in RSS form. The URL will include an encoded reference to Search Result List from which the RSS Feed is derived.

The URL includes a single parameter which identifies the GUID of the List from which the Feed is derived.

As with all RSS feeds exposed by SharePoint access to the feed will be controlled by NTLM Authentication.

Consuming SharePoint RSS Feeds

Having identified the SharePoint RSS Feed URL, we're able to publish the feed as a Presto Syndicated Service.

The following information is required to register a SharePoint RSS Feed as a Presto Syndication Service:

1. RSS Feed URL
2. NTLM credentials, Username, password and domain.

Optionally:

• Choose an existing or create a new Presto Application to which the Serivce will be assigned.
• Select a Service Provider to be associated with the service.
• Choose one or more service Tags, for example you may wish to tag services with the name "SharePoint" and all services from a given site with the SharePoint Site name.

Password credentials are stored in encrypted form.

The full procedure for publishing a Syndicated Service to Presto is detailed here Service Explorer Publishing a Syndication (RSS/ATOM) Service

Having published and activated the service, the service is now mashable.

• We can expose this service as a mashlet using MashletMaker.
• We can combine the service with others to create a Mashup using Wires or Mashup Studio.

Mashing SharePoint RSS Feeds with Presto Wires

Mashing SharePoint RSS Feeds with Presto Wires (Coming soon) provides an example of Mashing a SharePoint RSS Feed with an external RSS Feed and publishing the resulting merged feed as a Mashlet.

This post is part of a many-part series about Mashups and Microsoft SharePoint.  You can read about the entire series at http://www.jackbe.com/enterprise-mashup/blog/mashing-sharepoint-introduction.