Feeds

1
Feeds

• Computer Applications to Medicine
• NSF REU at University of Virginia
• July 27, 2006
• Paul Lee

2
Goals

• To become familiar with the .NET/ Microsoft SQL
  2005 environment.
• To learn about RSS and how to generate RSS feeds
  from a database.

3
Motivation

• Doctors are constantly busy and have little time
  to check on the current state of medicine.
• RSS Feeds provides a means of making short up to
  date announcements without the audience having to
  read through pages of documentation.
• RSS feeds can be read by several popular devices
  (i.e. i-pod, tablet pc, etc.).

4
Current state-of-the-art

• RSS 2.0, is used widely on the internet for
  distributing summary data of articles or events
  dynamically.
• 3 popular RSS specifications include RSS 2.0,
  RSS 1.0, and RSS 0.91. RSS 2.0 is the latest
  version.
• I encountered 3 types of methods for generating
  RSS feeds
• Manually coding and updating your RSS page.
• Store a text file in a database, and for every
  request generate an RSS file from the text file
  using .NET and .NETs HTTP handler to answer the
  request by sending the generated XML file to the
  requestor (used by James H. Byrd for magazines
  Computer Companion and Logical Tips).
• Store your data in a database and generate an RSS
  file using .NET only when changes have been made
  (used by Nick Bradbury to generate feeds for his
  FeedDemon FAQ).

5
RSS Security (Very New)

• A number of aggregators now have support for SSL
  and Http authentication.
• However, practically no feeds actually use
  security measures.

For more info go to Private RSS Feeds Support
for security in aggregators by Steven
Garrity http//labs.silverorange.com/archives/20
03/july/privaterss RSS security by Greg
Reinacker http//www.rassoc.com/gregr/weblog/arc
hive.aspx?post775 RSS security, part deux
Web-based aggregators by Greg Reinacker http//
www.rassoc.com/gregr/weblog/archive.aspx?post779
6
Sample RSS Feed

• lt?xml version"1.0" encoding"iso-8859-1" ?gt
• ltrss version"2.0"gt
• ltchannelgt
•   lttitlegtRSS Feeds channellt/titlegt
•   ltdescriptiongtGeneral RSS Feed
  Listlt/descriptiongt
•   ltlinkgthttp//www.virginia.cs.edu/lt/linkgt
•   ltlastBuildDategtMon, 24 Jul 2006 145022
  GMTlt/lastBuildDategt
•   ltdocsgthttp//backend.userland.com/rsslt/docsgt
•   ltgeneratorgtRSS.NET http//www.rssdotnet.com/lt/g
  eneratorgt
• ltitemgt
•   lttitlegtConsumer Reports Health Guidelt/titlegt
•   ltlinkgthttp//www.consumerreports.org/rssfeed/crm
  galerts.xmllt/linkgt
•   ltpubDategtMon, 24 Jul 2006 145022
  GMTlt/pubDategt
•   lt/itemgt
•   lt/channelgt
•   lt/rssgt

7
Requirements

• The RSS feed must be updated each time a change
  has been made to the data in the database.
• GUIs must be user friendly for both the client
  and admin application.
• For the Client application
• The application must be able to read and display
  RSS feeds.
• The application must update the information from
  the RSS feed in a timely fashion wasting a
  minimal amount of resources.

8
Requirements Part 2

• Requirements for Client Application continued
• The user must be able to choose from a list
  provided which RSS feeds to subscribe to in
  addition to the hospital feed.
• The user should also be able to subscribe to any
  other feed.
• Clicking on a link should either open a browser
  page or load the page in the application.

9
Requirements Part 3

• For the Admin application
• The application should verify that the user is an
  administrator.
• The user must be able to view an RSS feed as well
  as its source data in the database.
• The user must be able to insert and/or delete
  entries in the database.

10
My approach to solution

• Create a database to hold announcements and lists
  of RSS feeds.
• Create a client program allowing the user to
  choose which RSS feeds to join and view those
  feeds.
• Create an administrative program allowing the
  viewing of generated RSS feeds as well as
  providing an interface for creating/updating a
  RSS feed.

11
Categorizing RSS Feeds
Doctor Oriented Feeds
Patient Oriented Feeds
General Feeds
12
Groups Example
Users
User 1
User 2
User 3
Relation to Hospital Groups
User Created Groups
13
Some System Specs

• The client/admin programs is written using the
  .NET environment.
• RSS.NET, an open source class library, will be
  used for writing and reading RSS feeds.
• A web service is utilized to mediate between
  clientapp and the database.

14
Deliverables

• A method for creating and maintaining RSS feeds.
• client and admin applications for viewing and
  editing RSS feeds.

15
Results

• adminapp and clientapp both ran on a different
  computer from the server in the lab after working
  with windows firewall.
• Both applications fulfilled all requirements for
  this project except for adminapp, which is
  lacking an authentication module.
• A method for users to create their own private
  rss feed and form groups was implemented in
  clientapp.

16

• Demonstration

17
Evaluation

• Time delay during updates is significant, but
  seems to be about the same for RSS Bandit, a free
  desktop RSS aggregator built on .NET.
• Both client and administrative applications need
  more secure features in order for them to be used
  as a means for handling sensitive data safely.
• For some, the long term caching mechanism is a
  useful feature for creating an archive of old RSS
  feeds, but may be a waste of hard drive space for
  others.
• There is an issue with the updating of feeds
  without publish dates on their items.
• There is no option for updating individual feeds.
  Updating all feeds can be an annoyance due to
  the update time.
• adminapp is inflexible and limited in that the
  connection to server, database, and tables is
  hard coded. Additional databases and tables
  cannot be created or added.
• RSS 0.91 feeds could not be written using
  RSS.NET.
• Much more work can be done to both applications.

18
Conclusions

• RSS is a powerful tool for publishing news,
  viewing short summaries of web pages, archiving
  RSS items, and communicating with groups of
  users. Much more work can be done with RSS in
  terms of secure communications and application.

19
Future Work

• Strip html tags that pose to be security issues.
• Add support for the ATOM standard.
• Port the client application to other devices.
• Add support for SSL and Http authentication.
• Add search capability of cached feeds and/or
  associated web sites.
• Add caching capability of web sites associated
  with the items in the cached feeds.