Processing Domain-Specific. Modeling Language. Fabien Latry, Julien Mercadal, and Charles Consel. Phoenix Research Group INRIA / LaBRI

Transcription

1 Processing Domain-Specific Modeling Language A Case Study in Telephony Services Fabien Latry, Julien Mercadal, and Charles Consel Phoenix Research Group INRIA / LaBRI GPCE4QoS October 2006

2 What is a Domain-Specific Language? Software Engineering s Viewpoint Modeling the domain» Domain-specific notations and concepts,» A solution as a model,» Experience in the domain. Programming Language s Viewpoint Programming the domain» Domain-specific constructs and semantics (restrictions and extensions),» A solution as a program,» Experience in the domain, but also in programming. GPCE4QoS - October

3 What is a Domain-Specific Language? Domain-specific language = A language specific to a domain Visual * flowchart * form-based Textual * declarative * scripting Horizontal * business logic * database Vertical * telephony * banking GPCE4QoS - October

4 What is a Domain-Specific Language? System; System; System.Collections; System.Collections; System.ComponentModel; System.ComponentModel; System.Data; System.Data; System.Diagnostics; System.Diagnostics; System.Web; System.Web; System.Web.Services; System.Web.Services; XYZ.GapOrdering; XYZ.GapOrdering; XYZ.GapOrdering.ClientLibrary; XYZ.GapOrdering.ClientLibrary; namespace namespace GapWebService GapWebService { { /// /// <summary> <summary> /// /// Summary Summary description description for for Service1. Service1. /// /// </summary> </summary> public public class class GapService GapService : : System.Web.Services.WebService System.Web.Services.WebService <?xml version="1.0" encoding="utf-8"?> <!-- Commentaire --> <élément-document xmlns=" xml:lang="fr"> <élément>texte</élément> <élément>élément répété</élément> <élément> <élément>hiérarchie récursive</élément> </élément> <élément>texte avec <élément>élément</élément> mêlé</élément> <élément/><!-- élémént vide --> <élément attribut="valeur"></élément> </élément-document> R 0.1R 0.1R R +v 0.7CR C C 0v GPCE4QoS - October

5 What is a Domain-Specific Language? Modeling DSLs vs. Programming DSLs Compilation Verification of domain properties 1 domain = n DSLs Representations, Paradigms, Degrees of expressivity, Types of end-user. GPCE4QoS - October

6 Our Approach Aim Improving the compilation and the verification of DSLs. Idea Introducing a layered view of DSLs, Leveraging high-level tools. GPCE4QoS - October

7 A Layered DSL Approach DSML Modeling DSPL Programming Implementation Implementation DSML (modeling DSL)»Covers sub-domains/views,»checks domain properties,»targets the DSPL. DSPL (programming DSL)»Covers a domain,»interfaces domain/implementation,»generates implementation. GPCE4QoS - October

8 A DSPL as a Pivotal Layer Preference / Constraint / Trust level / Purpose / Abstraction level / DSML 1 DSML 2 Modeling DSPL Programming Implementation 1 Implementation 2 Implementation Advantages of the separation of concerns»simplification in the compilation,»reusability: variety of DSMLs for a DSPL,»Evolutivity of the DSML. GPCE4QoS - October

9 The Processing of DSMLs Specific treatment at each layers Compiling a DSML High level, Simple, deferring implementation aspects to the DSPL compiler. Verifying a DSML Domain-specific computations, Aspect relevant to domain-specific verifications. High-level tools for both processes. GPCE4QoS - October

10 Our Case Study The domain of telephony service creation. Call Processing Language (CPL) XML-based scripting language, Domain experts, non-programmers. Session Processing Language (SPL) Abstracts over underlying protocols, platform, Programmers. High-level tools Stratego/XT : program transformation tool, TLA+ : formal specification language. GPCE4QoS - October

11 The Processing of CPL CPL Program Stratego/XT Stratego/XT SPL Program TLA+ Specification Compilation TLC Error Report Verification GPCE4QoS - October

12 Compilation: From CPL to SPL <?xml version="1.0" encoding="utf-8"?> <cpl> <incoming> <location <proxy> <busy> <location <proxy /> </busy> <otherwise> <address-switch field="origin"> <address <location url="tel: "> <proxy /> </location> </address> </address-switch> </otherwise> </proxy> </location> </incoming> </cpl> CPL service example { processing { dialog { SPL response incoming INVITE() { response r = forward 'sip:bob@phone.example.com'; if (r == /ERROR/CLIENT/BUSY_HERE) { return forward 'sip:bob@voic .example.com'; else if (r == /ERROR) { if (FROM == 'sip:boss@example.com') { return forward 'tel: '; else { return r; return r; GPCE4QoS - October

13 Compilation: From CPL to SPL <?xml version="1.0" encoding="utf-8"?> <cpl> <incoming> <location <proxy> <busy> <location <proxy /> </busy> <otherwise> <address-switch field="origin"> <address <location url="tel: "> <proxy /> </location> </address> </address-switch> </otherwise> </proxy> </location> </incoming> </cpl> RuleRedirectNonTerminal : <location url="callee"> <proxy> <busy> stat1* </busy> <otherwise> stat2* </otherwise> </proxy> </location> -> [ response r = forward callee ; if ( r == /ERROR/CLIENT/BUSY_HERE ) { stat1* else { stat2* ] where new => r RuleFROMTest : <address-switch field="origin"> <address is= caller"> stat1* </address> <otherwise> stat2* </otherwise> </address-switch> -> [ if (FROM == caller) { stat1* else { stat2* ] service example { processing { dialog { response incoming INVITE() { response r = forward 'sip:bob@phone.example.com'; if (r == /ERROR/CLIENT/BUSY_HERE) { return forward 'sip:bob@voic .example.com'; else if (r == /ERROR) { if (FROM == 'sip:boss@example.com') { return forward 'tel: '; else { return r; return r; GPCE4QoS - October

14 Verification of Domain Properties Telephony properties No call loss, No redirection on the same address, No infeasible path. Incoming call 1 Does the sender s address contain "boss"? 2 3 yes Redirect call to Bob s cell phone no... Is the sender s address "sip:boss@example.com"? 4 yes no Redirect call to 5 Bob s voice mail Reject call 6 GPCE4QoS - October

15 Assessment Benefits of the layered view of DSLs Specific treatment at each layer, Simplification of the DSMLs processes. High-level compilation approach Compilation more amenable to existing high-level program transformation tools, A bridge between a DSML and its implementation. High-level verification approach Easier to reason about, Verification of domain-properties. GPCE4QoS - October

16 Conclusion An approach for improving the compilation and the verification of DSMLs. High-level compilation process Target a DSPL, Target a formal specification. Case study in telephony service creation. GPCE4QoS - October