Evaluation and testing

Evaluation and testing WUCM1

Testing large websites • Testing should be against agreed requirements • For large sites with dynamic pages (Java, ASP, Perl, etc.): • Use a development environment such as NetBeans, DreamWeaver or Visual Studio • Offers debugging services, break points, traces, variable contents, spying, etc. • Permits remote debugging WUCM1

Testing small websites • Start with fully specified checklist of expected functionality • Greenberg (1999) gives a good example. [] 1. Main page loads without errors [ ] 2. Banner frame loads banner [ ] 3. Hover functionality over each of the banner links [ ] 4. “About” is a link to about.htm [ ] 5. “Feedback” is a link to feedback.htm [ ] 6. “Advertise” is a link to ad.htm [ ] 7. “Awards” is a link to awards.htm [ ] 8. “Rings” is a link to rings.htm etc. WUCM1

Browser compatibility tests • Important to test your website using a variety of browsers • cannot assume it will look/operate the same in all • Use a range of different browsers and browser versions • Browsers you do not have, e.g. for a Mac? (www.danvine.com/icapture) shows the ‘look’ • Some tools permit you to exercise a range of browsers • e.g. see the compatibility viewer http://www.delorie.com/web/wpbcv.html • How do you record your test results? • Very least is a tick in the box, as above WUCM1

Web server tests • Most tests presume the error is in the HTML, ASP, Perl, JavaScript etc. • Possible that there are faults in the web server configuration • How to modify site test plan to investigate the server environment? WUCM1

Link tracking and checking 1 • Tests should involve the link integrity of the web structure • Web development systems (e.g. DreamWeaver) usually include a Link Checking option • Link checking: • Validates your structure • Highlights broken links • Identifies orphan files • Lists external links WUCM1

DreamWeaver example WUCM1

Link tracking and checking 2 • Employ a 'web weeder' to check for: • Out of date links • Out of date documents • Check external links: • Tedious to do manually • Automated tools make this chore easier • See the Web Design Group's links page http://www.htmlhelp.com/links/validators.htm WUCM1

Link checking tools 1 • Options for installation: • On your web server • On the service provider’s server • On your development machine • Examples of external services: • The fee based WebAlarm system • http://www.linkalarm.com/ • NetMechanic • http://www.netmechanic.com/ WUCM1

Examples WUCM1

Link checking tools 2 • Example – download link checker: • Xenu’s Link Sleuth • http://home.snafu.de/tilman/xenulink.html • Someone needs to react to the Link Check report: • Updating links if the service has moved • Rewriting the pages if the target has been retired • Advising users of problems in the past, so at least your users are forewarned WUCM1

Link checking tools 3 • Users who tried to use your broken links • Use a tool to identify them – 404 errors • Contact them (if identifiable) • might be good PR? • WatchFire used to offer a range of white papers • http://www.watchfire.com/ • Check on Google WUCM1

Use of log files • Some common log file formats: • Common • Referrer • Agent • User defined possible: • Would need you to produce your own analysis software • Seldom worth the trouble WUCM1

Log files 1 • Text in the format string not a place holder; is just sent as plain text • Placeholders are replaced with their data • LogFormat "Host=%h URL=%U Server=%V Port=%p” • Log files can be useful to look through, but you will need help WUCM1

Log files 2 • Simplest use is to just filter and display the most recent entries – • suitable for a human to monitor • Benefits of visual inspection: • Check that pages deliverable (no 404 errors) • Check that security is working properly • Check that CGI is working properly • … WUCM1

Session logs 1 • Logs that track a single user session • What pages were viewed? • What order were the pages viewed in? • Was a purchase made (or some other goal reached)? • Was enquiry abandoned? • Not easy to achieve as web inherently “stateless” – each page is a new transaction! WUCM1

Session logs 2 • Techniques – see Nobles (2001): • Cookies – using cookies to capture and log session data • Database-driven pages – using the code to capture session data • Parsing server logs [next slide] • Web bugs – hidden <img> tagged files that trigger unseen activity at the server • often 1 pixel square • Non-covert <img> tracking – the more polite version of web bugs WUCM1

Log file analysis tools • Many tools available – try a Google search • Analog (free from http://www.analog.cx) is typical – see Wainwright or Nobles • Analog system is configured with a .cfg file much like Apache’s • Some examples from the website WUCM1

Analog examples 1 WUCM1

Webalizer example 1 WUCM1

Webalizer example 2 WUCM1

Uses of log file analysis • Qualitative checks: • identify (and then eliminate) any 404 file not found log entries • Nobles (2001) lists a number of "quantitative" uses: • How many page views is your site getting per day? • How many user sessions is your site getting per day? • How long are users staying on your pages? WUCM1

More uses • Which pages of your site are requested the most? • Which pages are requested the least? • What are the top ENTRY pages for your site? • What are your top EXIT pages? • Which pages are being viewed by themselves, where visitors are not even clicking to go to another page? WUCM1

Even more uses • Are visitors from other countries visiting your site? • Which sites are sending you the most visitors? • What are your top-referring search engines? • Which keywords are searchers using to find your site? • How many of your visitors are using older browsers? • Which search engine spiders have visited your site recently? WUCM1

Web usage statistics • Web statistics suffer from a number of problems: • Caching and proxy servers hide activity • Some users hide behind “anonymising” services • Most web pages built from very many small files – how to count? • Distinction between pages and hits WUCM1

Load testing • Need a feel for the behaviour of your web server under different levels of load • A baseline measurement is vital for: • planning for growth • identifying and dealing with DoS attacks • Tools include: • Mercury Interactive’sLoadrunner • RSW Software’s E-Load • Segue Software’s Silkperformer WUCM1

Evaluation • Checking to see if the website can be used effectively by its intended audience • Evaluation in most cases will involve a human in the loop • For a good technical set of examples see Spool, (1999) • Not the main focus for WUCM1 WUCM1

Search engines/directories • How will search engines and directory services interact with your site? • Nobles (2001) considers the matter from a number of perspectives, e.g.: • Key words and interaction with spiders or robots • Optimising your site to facilitate search engine spiders • Deprecated features of HTML • Web directories and how to get included WUCM1

Validation services 1 • Validators can for example check for a number of different features, including: • How usable are your pages to people with disabilities • Conformance to the HTML specification (World Wide Web Consortium - W3C.) • See The Web Design Group list of links to different validation services • http://www.htmlhelp.com/links/validators.htm WUCM1

Validation services 2 • Generally two ways of using a validation service: • Submit your page to the validation service website and receive back a report page • Mount a copy of the validation software on your development system, and run your pages through this system • Like virus checkers, web validators need regular updates WUCM1

Validation services 3 • Two important validation services are: • The W3C HTML conformance validation • http://validator.w3.org/ • The accessibility validation services • http://www.cast.org/bobby/ • If you pass you get a logo, e.g. • Review access to 1000 commercial websites • http://www.drc-gb.org/publicationsandreports/2.pdf WUCM1

Evaluation and testing