optimisation of behaviour of component-based distributed systems

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Optimisation of behaviour of component-based distributed

systems

INRIA - I3S - CNRS – University of Nice Sophia-Antipolis

EPC SCALE

Galyna Zholtkevych

Internship Supervisor: Eric Madelaine

Sophia Antipolis, July 2014

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Motivation-component-oriented programming - defining the distributed component-based application

-safety behaviour - robust software for verifying fault-tolerance and valid behaviour of the components

-specification needs hierarchical components structure, asynchronous communication with futures between components

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Agenda

• Motivation• Background– Base: Grid Component Model– Robust software: Vercors Components Editor– Robust software: graphical formalisms– Behaviour specification: Grammar SM labels

• Xtext• Current state and contribution • Future work

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Grid Component Model

• hierarchy, distribution, one-to-many communications, reconfiguration capabilities;

• -deployment, scalability, autonomic behaviour and asynchronous communication (ProActive Parallel library);

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Vercors Components Environment• maintain implementation of the valid behaviour:

– precise denition of interfaces– hierarchical and modular design– VCE is based on GCM approach– for specifying behaviour of components VCE uses UML approach– maintain default vce types

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VCE graphical formalisms

Components diagram

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VCE formalisms

• Diagram of one component

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VCE 3.1.12

• Basic environment: Obeo Designer (base: Eclipse, developing graphical VCE formalisms).

• Tools: – ADL2N (multiplatform tool in Java, building hierarchical an parametrized

behaviour model represented in pNETs from the specification of architecture and behaviour)

– Xtext 2.4.1 (integrated to VCE, parsing the grammar for behaviour specification)

• VCE Wizard (integrated application creating models for specifying VCE graphical formalisms (VCE components model, UML model, model for VCE types))

• Prototype version is used for teaching in the LIAMA summer school in Shanghai

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SM labels parametrization• Behaviour models are parametrized.

pLTS (parametrized labeled transition system [1]) describe:– Primitive internal behaviour– Semantic-level process generated from

GCM architecture by ADL

Example of Primitive internal behaviour

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Grammar of SM labels

• BNF grammar, behaviour for labels

• Java Cup Parser - parser generator that produces a parser written in Java

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Internship Subject

• New alternative: Xtext instead of Java Cup implemented before

• Validation rules for the state machines: checking the correspondances between the built grammar and the valid behaviour

• Semantic translation of the state machine to pLTS has not been done

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Agenda

• Motivation• Background• Integrating Xtext to VCE– Why Xtext– Grammar– Editor– Computing the context

• State Machine and pLTS• Current state and contribution • Future work

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Why Xtext

• Autocomplete• The ability to refer to the VCE formalisms

(compatible with Ecore models)• The ability to refer to the UML formalisms

(cross-reference)• Compatible with Eclipse• Code generation

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Xtext Grammar

• Part of the grammar for the labels of State Machine that was implemented and after extended • Behaviour model is

saved in the file as a String. • For dealing with the

real Model the objects with type EObjects are used.

Transition_label = “[“ Guard_Expr “]” “/” Stats “.” | “[“ Guard_Expr “]” “.” | “/” Stats “.”Stats = Stat | Stat “;” StatsStat = MCall | Assign | Return Assign = Variable := Expr | Variable := MCallExpr = Variable | Constant | Expr Bop Expr | “(“Expr”)”Mcall = ”call” Interface “->” Operation “( )” |

”call” Interface “->” Operation “( “ Args” )” |

”call” Operation “( )” | ”call” Operation “( “ Args” )”

Interface = ID”.”IDOperation = ID”.”IDBop = && | || | + | - | * | / | == | >= | <=|!=

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Xtext Editor

All the behaviour model creating by Xtext grammar appears in Xtext Editor

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Computing the context

• Cross-reference is one of the main features in Xtext

• The ability to refer to the objects that are defined elsewhere

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Agenda• Motivation• Background• Xtext• Current state• Future work• State Machine and pLTS• Millestones for the future work

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Current State and Contribution• Learning the subject. Learning Xtext.• Xtext was integrated in VCE

– Availability to refer to VCE formalisms has been implemented (Oleksandra Kulankhina, SCALE)

– Integrating tools for VCE formalisms (Bartlomeij Szejna, Galyna Zholtkevych, SCALE)

– Part of the real Xtext grammar has been created to give Xtext an attempt (Bartlomeij Szejna, Galyna Zholtkevych, SCALE)

– Part of the computing the context has been implemented (Galyna Zholtkevych, SCALE).

– Xtext Editor has been implemented (Bartlomeij Szejna, Galyna Zholtkevych, SCALE). Getting the context from the diagrams. Modifying code

– Saving model to the file has been implemented (Bartlomeij Szejna, SCALE)

• Latest prototype of VCE has been tested (Galyna Zholtkevych, SCALE)

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Agenda

• Motivation• Background• Xtext• Current state and contribution• Future work• Semantic translation SM to pLTS• Millestones for the future work

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Semantic translation SM to pLTS

• Semantic translation from the State Machine to pLTS has to be done– Validation rules:• State Machine’s labels behaviour• Diagram validation: static semantics verification; type

checking - verifying fully typed programs, compatibility of operands and operations

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Millestones for the future work

• Filtering methods called from the transition label as a part for user’s tools• Validation rules • Translation the State Machine to

pLTS

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Thank you for the attention!• References:• Verifying Safety o Fault-Tolerant Distributed Components,

Rabéa Ameur-Boulifa, Raluca Halalai, Ludovic Henrio, Eric Madelaine: http://hal.inria.fr/view_by_stamp.php?label=INRIA-RRRT&langue=fr&action_todo=view&id=inria-00621264

• Behavioural Semantics for Asynchronous Components, Rabéa Ameur-Boulifa, Raluca Halalai, Ludovic Henrio, Eric Madelaine: http://hal.inria.fr/hal-00761073

• Vercors platform: http://www-sop.inria.fr/oasis/index.php?page=vercors

• Xtext Language Development http://www.eclipse.org/Xtext/• Obeo Designer homepage http://www.obeodesigner.com/

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Future proxies

• Specifying asynchronous communication between 2 active objects.

• So needs of future proxy– To perform remote call by

component– Waiting for the response value –

future value got by the Get_value method

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Asynchronous communication

Example: facebook, mail, mobile , ….