Agile Architecture
Odessa
Johannes Brodwall, Chief scientist
Exilesoft Global
What is an architect?
From greek Arkhi-Tecton
Tecton: Builder
Arkhi: Chief.
Like “Arch angel”
Or “Arch nemesis”
What is an architect?
“Chief builder”
What is an architect?
(Exilesoft definition)
A solution architect is
someone who understands
the problem of the customer
and uncovers and
communicates
a feasible solution
A solution architect is someone who
understands the customer’s
problem (including contraints, context,
domain knowledge) and uncovers
(though a team effort) and
communicates (with credibility) a
feasible solution (primarily, but not
exclusively technical)
Uncover problem
vision, stakeholders, usage flow
Describe problem
context and domain model
Describe solution
deployment, implementation model
Simplify architecture
feature oriented structure
Deliver software
rainbow plans
• Describing architecture
• Simplifying architecture
• Delivering architecture
• Delivering software
Part I:
Describing
architecture
•
•
Understanding problem
• Uncovering solution
Communicating architecture
Understanding the
problem
(Tool time)
For some stakeholder
Who has a goal
The Odessa agile user group (?)
Is a type of activity
Which gives a capability.
Unlike most relevant alternative
This has a distinguishing attribute.
For __________________
Who ________________
The Odessa agile user group (?)
Is a _________________
Which ________________.
Unlike ______________________
This _______________________.
Example
«Smidig» conference application
Example vision
statement
For Agile practitioners
Who need to expand on their experience and network
The Smidig conference
Is a networking event
Which connects you with other Agile practitioners.
Unlike traditional conferences
This presents the experience of many people through
lightning talks.
For Conference organizers
Who want to organize a good conference
The Smidig conference app
Is a web application
Which eliminates unnecessary work.
Unlike commercial conference apps
This is optimized for the large number of talks
we have and allows us to make changes fast.
Example
stakeholders
Speaker
Attendee
Organizer
Description
• Experienced
• New speaker
• Passionate
Description
• Knows about agile
• Works in project
• Norwegian
Description
• Volunteer
• Works in evenings
• Has network
Duties
• Register talk
• Upload slide
• Give talk
Duties
• Pay for conference
• Get approval to go
Duties
• Select talks
• Follow up
payments
Values
• Constructive
feedback on talk
• Easy CfP
• Fast answer
Values
• Easy registration
Values
•
Easy selection process
•
Good information
overview
•
Never lose a participant
•
Financial transparency
Sponsor
Description
• Busy
• Manager
• Not very interested
Duties
• Provide logo
• Pay sponsorship
Values
• Informal
communication
• Easy evaluation
Example usage flow
Attendance
1.
2.
3.
4.
5.
6.
7.
8.
9.
Agile project practitioner wants to learn
Attendee goes to Smidig website
Attendee registers
Attendee pays
Attendee receives confirmation mail
Organizer can see the registration
Organizer sends reminder email to attendee
to come
Organizer prints badges for attendees
Attendee shows up at Smidig and has an
excellent time
Speaker
1.
2.
3.
4.
5.
Agile experts wants to share knowledge
Potential speaker goes to Smidig website
Potential speaker registers personal info
Potential speaker registers talk
Potential speaker receives registration confirmation
email
Organizer sees registered talk and can market
speaking opportunities
Organizer accepts talk for confence
Speaker receives acceptance email
6.
7.
8.
–
9.
10.
Alternative: Speaker withdraws talk – organizer updates
the talk and selects another
Organizer prints badges for speakers
Speaker shows up at Smidig and gives talk
/Understanding the
problem
Uncovering a
solution
Example context
model
Participant
Speaker
Organizer
Paypal
Smidig2011.no
Printing
company
Example domain
model
User
•
•
•
•
•
•
Comment*
•
•
•
Title
Text
Created date
*
Registration
Name
Email
Company
Phone
Password
Accepts email?
•
•
•
•
•
•
Ticket type
Price
Paid amount
Paypal ref
Payment date
Invoice address [optional]
*
Speaker
*
Talk
•
•
•
•
•
•
•
Title
Description
Tags[]
Slide file
Status : {pending,
accept, reject}
Email_sent
Position
Period
•
•
•
•
Stage
Title
Time of day
Day
Example
deployment model
Web user
html/http
Developer
git push
git pull
github
git push
git.heroku
Smidigconference
(Rails)
Heroku
http
Paypal
smtp
Smtp.dreamhost.com
smidigdb
PostgreSQL
Example
implementation
diagram
Browser
Smidig2012.no
Paypal.com
1. POST /users
Save user info
2. Redirect to paypal
with return_url and notify_url
3. Perform payment
4. POST /payment_notifications
Update user
info
5. Redirect to return_url
5. GET /user/<id>
Show user info
/Uncovering a
solution
Communicating a
solution
Vision
Stakeholders
Usage flow
Context
Domain model
Implementation
Deployment
Does the architect
have to do this
herself?
Team effort
/Communicating a
solution
/Describing
architecture
Part II:
Simplifying
architecture
•
• Lasagna architecture
Feature oriented architecture
• Deployment constraints
Lasagna
architecture
PersonController
PersonService
PersonRepository
PersonDao
PersonControllerImpl
PersonServiceImpl
PersonRepository
Impl
PersonDao
Impl
SessionFactory
Controllers
Services
Managers
Workers
Repositories
Controllers
DTO
Services
Mapping
Domain
Managers
Workers
Repositories
Customer
Invoice
Order
Product
Tidying up art (Ursus Wehrli)
Feature oriented
architecture
Coherence
• What changes together
lives together
Tolerance
• What should be different
can be different
Meaning
• What is central in domain
is central in code
Your thinking is
contrained by
technology fashion:
Controllers
DTO
Services
Mapping
Domain
Managers
Workers
Repositories
Your solution is
constrained by
deployment
Web user
Browser
JSON/http
DTO?
Web Application
Consumer
DTO
Controller
SOAP
Service
DTO
Web Service
Database
Web user
Browser
JSON/http
DTO?
Web Application
Controller
DAO
Database
Web user
html/http
Controller
Web Application
DAO
Database
Web user
html/http
Reverse proxy
html/http
Controller
Web Application
DAO
Database
Web user
Controller
Rich client
DTO
Objects
over http
DTO
Web Application
Database
Web user
Controller
Rich client
DTO
Consumer
Web
service
Service
DTO
Web Application
Database
Web user
External client
Browser
JSON/http
Controller
DTO?
Web Application
Consumer
DTO
SOAP
Service
DTO
Web Service
DAO
Database
Web user
External client
Browser
JSON/http
Controller
Service
DTO
Web Application
DAO
Database
/Simplifying
architecture
Part III:
Delivering software
• Common sprint problems
• Demo driven development
• Rainbow plans
Common Sprint
problems
User stories without
context
Every feature must be
perfect at first try
Users don’t understand the
demo
One-sentence
Scrum
We demonstrate progress
at regular intervals
It’s all about the demo
We demonstrate progress at
regular intervals
Progress towards
what?
Usage flow
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Something happens in the real world
The event is communicated to the system
The system does something
Someone does something with the system
…
…
…
…
…
Some goal is achieved
Rainbow plan
Usage flow: frugalflights.com
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
What would you do
in Sprint 1?
Usage flow: frugalflights.com
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 1: Walking skeleton
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 2: SMS support
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 3: Complete workflow
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 4: Complete SMS
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 5: Web pages
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 7: Integration
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
Sprint 8: Spit-and-polish
1.
2.
A customer wants cheap vacations
The customer signs up for daily or weekly notifications of special
flight offers
Periodically the System checks which customers should get
notifications
The System checks for offers that matches the customer’s travel
preference by looking up flights with the travel provider system
The System notifies customer of any matching offers via SMS
3.
4.
5.
•
6.
Variation: The System notifies customer of any matching offers via
email
The customer accepts the offer via SMS
1.
7.
8.
Variation: The customer accepts the offer on the system website
The System books the tickets on behalf of the customer
The system confirms the booking by sending an SMS to the
customer
9. The customer can at any point see their active offers and accepted
offers on the system website
10. The customer enjoys a cheap vacation!
/Delivering software
Conclusion:
Travel light – 7 perspectives
Domain oriented architecture
Sprint with a (rainbow) plan
What’s the common
theme?
Usage flow
Good architecture
comes from
understanding usage
Thank you
[email protected]
http://johannesbrodwall.com
http://exilesoft.com
http://twitter.com/jhannes
•
• Vision
• Stakeholders
• Usage flows – rainbow plans
• Context
• Domain
• (Simple) Deployment
(Feature oriented) implementation