Workflow systems

Myths, Truths and Wishful Thinking
Workflow Systems
Brandon Satrom
devLink2010
http://speakerrate.com/talks/4108

About Me
Technology Evangelist @ Microsoft
Software and Enterprise Architect
Based in Austin, TX
Husband and Father

Why are you here?
What is "workflow"?
What makes a “Workflow System” different?
What kind of problem is workflow designed to solve?
Can workflow problems only be solved by tools?
Are workflows always visual?
How do I design a “workflow system”?

You Want The Truth?

What comes to mind when you hear “workflow”?
Word Association

Visual

Process Automation

Modifiable

Can be maintained by someone other than the original developer

Six-Figure Cost

Others?

Here’s the truth…

Our perception of workflow is wrong…

Maybe “Workflow” can be simple…

State Machine Demo

A workflow is a depiction of a sequence of operations, declared as work of a person, a group of persons, an organization of staff, or one or more simple or complex mechanisms. Workflow may be seen as any abstraction of real work, segregated in workshare, work split or other types of ordering. For control purposes, workflow may be a view on real work under a chosen aspect, thus serving as a virtual representation of actual work. The flow being described often refers to a document that is being transferred from one step to another.
– from http://en.wikipedia.org/wiki/Workflow
Workflow: The Cure for Insomnia Definition

Workflow: simplistic definitions
“abstraction of real work”
“coordination of work in a system”

Isn’t that CODE?

The Difference is…

HUMANS are the process…

…TIME Passes...

…And The only constant is CHANGE.

Qualities of Workflow systems…

Declarative

External Stimulus
Persistence Store
Persistent

Dynamic
Business Change
Activity F
Divert to new activity

Activity D
Activity E
Rules Store
Configurable

Centrally Defined

static SessionSaga()
{
Define(() =>
{
Initially(
When(NewSession)
.Then((saga, message) => saga.NewSessionStarted(message))
.TransitionTo(SessionActive)
);
During(SessionActive,
When(FeedbackCheckRequested)
.Then((saga, message) => saga.CheckForFeedback(message))
When(new Timer()
.StartOn(session.Start)
.RunAtInterval(session.CheckInterval)
.Until(session.End))
.Then((saga, message) => saga.CheckForFeedback(message))
When(SessionComplete)
.Then((saga, message) => saga.SessionEnded(message))
.Complete()
);
});}
… though not necessarily visual.

Not just for workflow…
State machine
Saga
Service Buses
Workflow

Saga Demo (MassTransit)

Visual?

The dangers of seeing too much…

Workflow Demo (WF 4.0)

When Adopting Workflow, Consider…
Complexity of the problem
Skill level of development staff
Who keeps it running?
Value of a visual representation

Any GOOD system will encourage good design…
Declaratively define the FLOW
Define discrete, separate ACTIVITIES
Keep the RULES out of code

What is "workflow"?
What makes a “Workflow System” different?
What kind of problem is workflow designed to solve?
Can workflow problems only be solved by tools?
Are workflows always visual?
How do I design a “workflow system”?
Did We Answer These?

Ruby Statemachine :: http://bit.ly/rstatemachine
MassTransit:: http://masstransit-project.com/
WF4 :: http://bit.ly/wf4-msdn
WebMatrix :: http://bit.ly/devlink-wm
Demo Source :: http://github.com/bsatrom/WorkflowSystems2010
Resources

Questions?
Email: brsatrom@microsoft.com
Twitter: @TheSatch
Blog: www.userinexperience.com
Rate this talk: http://speakerrate.com/talks/4108

http://www.userinexperience.com	33
http://userinexperience.com	13
http://amurillo.typepad.com	1

Workflow systems

by Brandon Satrom on Aug 07, 2010

Accessibility

Categories

Tags

Upload Details

Usage Rights

3 Embeds 47

Statistics

Workflow systems — Presentation Transcript