The ACGT Workflow Editing & Enactment Environment

Giorgos ZacharioudakisInstitute of Computer Science, Foundation for Research &

Technology – Hellas (ICS-FORTH)

Introduction

DatabasesDatabases

FilesFiles

Data sourcesGrid computing

resources

Tools, algorithms,analytical services

Users

Integrated ACGTEnvironment

ACGT Workflow Environment

Workflow Editor

Visual compositionof web services and data sources

into workflows

BPEL workflow

description Workflow Enactor

Textual descriptionof workflows

into XML code (BPEL)

Orchestration & Executionof BPEL code

into grid resources

…

ACGT Workflow Editor

The ACGT Workflow Editor is:A web based system (AJAX, servlets, DB storage),

with no installation or configuration needed, easily upgraded and grid-security enabled.

The ACGT Workflow Editor aims:To provide a graphical environment for the end

users to build their scientific experiments, by combining the ACGT tools and facilitate their execution on the Grid.

Menus and toolbarsWhat can be put

in the workflow (services, files etc) Workflow drawing

areaProperties of the

selected items in the workflow (if any)Status

information

Editor overview

Editor Functionality Access to all the ACGT Tools

GridR, Mediator, Data access services etc

Graphical creation of workflows Separate storage area per user

Save and load “my” workflowsAccess to grid file system

Publish a workflow so other people can use it Run workflows Monitor their execution More to come …

“Intelligent” user guidance during workflow creation

Enactor

The ACGT Enactor is: An open-source BPEL engine for the execution

of workflows, based on their textual (BPEL -XML) description, which is dynamically generated from their visual representation.

The ACGT Enactor aims: To orchestrate and invoke the underlying web

services, which utilize the available grid-resources.

Challenges in using BPEL in the Grid

Standards compliance WSRF vs. WS-I

Security Currently, WS / BPEL do not support

GSI-based delegation of user credentials and rights

That was the leading cause for the introduction of a new Enactment Environment

Enactment Environment Features

Invokes underlying grid services (or other kind of services) Delegates user credentials by using

proxy service mechanism Monitors the execution of the

workflow Logs invocation info (input, results,

status)

ACGT Workflow EnvironmentACGT Workflow Environment

Enactor(e.g. ODE)

Enactor(e.g. ODE) Proxy B

Proxy A

GSI-secure

ACGT Service

3rd Party Service

Enactor Proxy

MyProxy

Certificate

CertificateId

Id

IdId

Certificate

Workflow WS-interface

LegendGSI Secured communication

WS (WS-I) communication

LegendGSI Secured communication

WS (WS-I) communication

Enactment Security Architecture

Certificate

Conclusions

BPEL is a mature technology

The ACGT Workflow Editor offers an integrated web based environment for the design of scientific workflows

The Enactment environment was needed to take advantage of the Grid security and its resources

Work in progress.. Stay tuned! New features are constantly added

We welcome user suggestions

Thank you!