RepoMMan: using Web Services and BPEL to facilitate workflow interaction with a digital repository


3 Νοε 2013 (πριν από 4 χρόνια και 8 μήνες)

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RepoMMan: using Web Services and BPEL to facilitate

workflow interaction with a digital repository

Richard Green


RepoMMan Project overview

User and University needs

A solution: BPEL and Web Services

Example workflows: deposit and metadata

Problems? What problems?

Future work

JISC Workflows activity and implementation meeting

Aston Business School

Tuesday 13

February 2007

RepoMMan project

Repository, Metadata and Management project

funded for two years to end May 2007... develop a BPEL
based, standards
compliant, Web
Services based, workflow tool for Fedora

Closely aligned with the University’s commitment to
deploy an institutional repository


Two strands:


user needs, documentation etc (BPEL, surveys,

Beginner’s guide etc)



Surface tool in University portal and/or Sakai C&LE

Hull’s vision for a DR

Hull’s vision for an Institutional Repository is an
extremely broad one

Conventional view was exposure of completed objects

Hull’s view encompasses storage, access, management
and preservation of a wide range of file types from
concept to completion

User needs

Survey and interviews revealed very wide range of file
types potentially to deal with

Users need

Storage (backed up)

Access (from anywhere)

Management (sharing, locking, versioning etc)

Some want preservation

Tool must fit users’ expectations and environment

Assist/improve doing what they already do

University needs


wide range of content, some public

some private, appropriate


Web Services, standards

BPEL, JSR168 etc


initially 2500 potential depositors

Open source software

Effective search & discovery

need good metadata

The repository grand plan


The repository will be a working environment as
well as a showcase

Aim is to provide storage, access, management
and potential preservation painlessly

Development based on user needs

Standards compliant, Web Service approach


Toolset to manage repository workflows for


Business Process Execution Language

(Active Endpoints Open Source version)

Web Services

Fedora repository software


scales to millions of flexible objects (NSDL = 6m+)


Fedora is not an ‘out
box’ solution

Provides the repository functionality for YOU to
use flexibly

Basic depositor workflows

Put object into repository

including some sort of structuring

Get object from repository


including at version level

Add metadata


= promote to public space

The RepoMMan deposit tool

‘Putting’ and ‘getting’ a file

Left hand side of screen gives browse capability
on user’s hard drive

Right hand side of screen shows the user’s
private repository space like a directory structure

(‘Folders’ are in fact repository collections)

Folders can be expanded and new folders

Objects can be further expanded to show

tier stack

tier stack

Model View Controller layer providing user

BPEL orchestrating Web Services (Fedora and
other) to move files and objects around

Fedora drawing on ID Management System and
University Storage Area Network

UML diagram for simple deposit

tier stack: simple deposit

‘Putting’ a file

Part of the BPEL process diagram

(Active Endpoints visualisation software)


switch depending on whether

object already exists


the left hand side branch creates

a new object


the right hand side modifies an

existing one


each of the globes with a ‘swirl’

round it is a Web Service call

BPEL and web services

BPEL can draw on any available Web Service

Access to an expanding range of data made
available through Web Services at Hull (and, of
course, elsewhere)

Which brings us to metadata!!!

Making public

Good metadata at the heart of effective search and

When a user wants to ‘make an object public’ we will
automatically add metadata

Potentially complex: BPEL to orchestrate

Has object already got metadata?

Derive metadata using tool(s)

Extract appropriate parts

Combine with contextual metadata

Allow user to edit

Create datastream(s) (DC, Rich metadata (UVa), preservation
metadata, etc)

Add to digital object

Metadata from web services

Much contextual metadata about the ‘author’
can be derived from University systems’ Web
Services or context

Technical metadata can be derived by using
tools such as JHOVE (as a Web Service)

Descriptive metadata about the content is the
Holy Grail?

Data Fountains (UC Riverside & NSDL)

Metadata from context & web svcs

metadata from
(LDAP, Portal,

Technical metadata
(JHOVE etc)

metadata from
content (Data
Fountains etc)

Allow user to edit /

Acknowledgements to the Arrow consortium

for the design idea

Problems? What problems?

Not a smooth journey!

Lessons: Don’t be a pioneer? Puppies don’t come free?

Active BPEL was/is fine

Fedora Web Services (v2.0, v2.1, v2.1.1) an issue

Web Services were rpc/encoded

BPEL and AXIS couldn’t always successfully validate responses

Fedora Web Services (v2.2) OK!

Web Services now document/literal

Next stages

Complete the RepoMMan deposit tool (!!!)

Internal testing

Trialling with users

scale trials

Complete the RepoMMan metadata work

project, develop further and deploy

Develop workflow tools for the admin side of the ‘make
public’ process, records management, preservation...

In time switch to DROID (for MIME type)? Shibboleth?

Project website and contacts


Contacts: (Manager) (Integration architect) (Director) (Software developer)