Post on 26-Dec-2014
description
Myths, Truths and Wishful Thinking
*Workflow Systems
Brandon SatromdevLink 2010
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?
*Word Association
What comes to mind when you hear “workflow”?
*Visual
*Tools
*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
*Workflow: The Cure for Insomnia Definition
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: 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
Activity A
Activity B
Activity A
Activity B
Activity C (Idle)
Activity D
(Active)
*Persistent
Persistence Store
External Stimulus
*Dynamic
Activity A
Activity B
Activity C
Activity D
Activity E
Activity F
Business Change
Divert to new activity
*Configurable
Activity A
Activity B
Activity C
Rules Store
Activity D
Activity E
*Centrally
Defined
*… though not necessarily
visual.
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() ); });}
*Not just for workflow…
*State machine
*Saga
*Service Buses
*Workflow
*Saga Demo (MassTransit)
*Visual?
*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
*Did We Answer These?
*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”?
*Resources
*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
*Questions?
* Email: brsatrom@microsoft.com
* Twitter: @TheSatch
* Blog: www.userinexperience.com
* Rate this talk: http://speakerrate.com/talks/4108