1 / 13

A Rule Based System For Web Site Verification

A Rule Based System For Web Site Verification. 1 Dip. Matematica e Informatica, Via delle Scienze 206, 33100 Udine, Italy. Email: demis@dimi.uniud.it . 2 DSIC, Universidad Politécnica de Valencia, Camino de Vera s/n, Apdo. 22012, 46071 Valencia, Spain. Email: jgarciavivo@dsic.upv.es.

ohio
Download Presentation

A Rule Based System For Web Site Verification

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. A Rule Based System For Web Site Verification 1 Dip. Matematica e Informatica, Via delle Scienze 206, 33100 Udine, Italy. Email: demis@dimi.uniud.it. 2 DSIC, Universidad Politécnica de Valencia, Camino de Vera s/n, Apdo. 22012, 46071 Valencia, Spain. Email: jgarciavivo@dsic.upv.es. D. Ballis1 J. García-Vivó2

  2. Motivations • Web Sites can have a very complex structure • Development and maintenance of Web sites are difficult tasks • Suitable methodologies are needed to verify Web sites w.r.t. syntactic as well as semantic properties!

  3. Formal Verification of Web Sites • GVerdi, the graphical evolution of the VERDI system, implements: • a rule-based specification language for specifying properties of Web sites • a verification technique for automatically checking whether the conditions are fulfilled and helping to repair faulty Web sites • it allows to detect incorrect and incomplete/missing Web pages

  4. Web Site Denotation • A web page is a ground term. Consequently, we represent a Web Site as a finite collection of ground terms of a suitable term algebra <member> member( <name> Peter </name> name(“Peter”) <surname> Hawkins </surname> surname (“Hawkins”) <status> Professor </status> status (“Professor”) <teaching> teaching( <course> Algebra </course> course (“Algebra”) </teaching> ) </member> )

  5. Specification Language • A Web specification is a triple (R, IN , IM) where • R is a set of user´s function definitions • IN is a set of correctNess rules • IM is a set of coMpleteness rules

  6. Specification LanguageCorrectness Rules • A correctness rule has the following form: l -> error | C where - l is a term - error is a reserved constant - C is a sequence of equations and membership tests w.r.t. regular languages e.g. project(year(X)) -> error | X in [0-9]*, X<1990

  7. Specification LanguageCompleteness Rules • A completeness rule has de following form: l -> r where - l is a term - r is a term s. t. Var(r)⊆Var(l) e.g. member(name(X),surname(Y))->hpage(name(X),surname(Y),status())

  8. Specification LanguageCompleteness Rules • Some symbols in the right-hand side of the rules can be marked by symbol # • Marks are used to select the Web pages on which we want to check a given condition. l -> #r e.g. hpage(status(“Professor”) -> #hpage(#status(#“Professor”),teaching)

  9. Rule Interpretation • Correctness Rules l -> error | C if l is recognized in some Web page of W and all the expressions represented in C are evalutaed to True (or C is empty), the web page is incorrect • Completeness Rules l -> #r if l is recognized in some Web page of W, then r must be recognized in some Web page of W which contain the marked part ofr

  10. An Example… … first of all, some GVerdi details to be considered: *XML/XHTML Web Pages * Function definitions of R are written in Haskell and saved in the file Defs.hs. Haskell functions which are defined in the Prelude standard library are available too. *wxHaskell-0.8, RegexpLib98 and hxml-0.2

  11. Conclusions • We presented the system GVerdi • Written in Haskell • 1100 lines of code (approx.) • Parser for web pages and specifications • Partial Rewriting, Verification Technique and Graphical User Interface • We are able to detect missing/incomplete and incorrect Web pages efficiently

  12. Future Work • Improving Regular Expressions capabilities • Verification of  full XML code (namespaces, attributes, etc.) • Moving towards the verification of dynamic Web sites

  13. END

More Related