event driven architecture in practice

Event Driven Architecturein practice

Domenico Musto

@mimmozzo domenico.musto@gmail.com

Who am I ?

What do I do ?

.NET

Web REST

AgileAutomation Testing

C#Team leading

Ruby

Agenda

• SOA

• EDA

• Communication patterns

• Advantages

• Disadvantages

• Q & A

Where is Agile going ?

PROCESS MATTERS

CODE MATTERS

Agile = no work upfront

Agile = no work upfront

No work upfront = no architecture planning

Architecture is not design

Agile = no work upfront

No work upfront = no architecture planning

Agile = no work upfront

No work upfront = no architecture planning

Agile = no design upfront

We can start now

A big code base…

• Build time

• Difficult to test

• No real boundaries

Does not scale

Event Driven Architecture

• Architecture is mainly business driven

• Business capabilities

Business capability

• Owns a part of the system

• Well defined responsibilities

• Owns a model (set of entities)

• Set of components (services, api)

• Isolated database

• Isolated deploy

SOA

FILES

DISCUSSIONS MEETINGS

TASKS

SOA FLOW

FILES

DISCUSSIONS MEETINGS

TASKS

SOA FLOW

FILES

DISCUSSIONS MEETINGS

TASKS

SOA FLOW

FILES

DISCUSSIONS MEETINGS

TASKS

SOA FLOW

EDA FLOW

FILES DISCUSSIONS MEETINGSTASKS

COMMUNICATION CHANNEL

Upload document with SOA

FILESCLIENTUpload document

TASKS NOTIFICATION PREVIEW

Upload document with EDA

FILESCLIENTUpload document

COMMUNICATION CHANNEL

TASKS NOTIFICATION PREVIEW

Communication patterns

• Database

• Files

• Messaging

Channels

• Logical address

• Datatype

• Events

• Commands

• Document Messages

Types of messages

A simple event

• ID

• Past sequence

• Informing the outside world that something happened

NewDocumentUploaded

{

Id:1,

DocumentId:100

}

Commands

SendEmail{

Id: 100,

To: ‘domenico.musto@gmail.com’,

From: ‘info@huddle.com’,

Subject: ‘Welcome to huddle’,

Content: ‘Enjoy’

}

Document Message

UserRegistered{

Id: 100,

Name: ‘Domenico’,

LastName: ‘Musto’,

Email: ‘domenico.musto@gmail.com’,

Twitter: ‘@mimmozzo’,

Avatar: ‘http://my.huddle.net/mimmozzo/avatar’

}

Reference Data

COMM. CHANNEL

NOTIFICATION

NewDocumentUploaded{

Id:1,DocumentId:100,WorkspaceId:200

}

FILES

PEOPLE

COMM.CHANNEL

UserRegistered{

Id: 100,Name: ‘Domenico’,LastName: ‘Musto’,Email: ‘domenico.musto@gmail.com’,Address: ‘London’,Twitter: ‘@mimmozzo’,Avatar: ‘http://my.huddle.net/mimmozzo/avatar’

}

COMM. CHANNEL

NOTIFICATION

Recipient

Id : intEmail : string

Eventual consistency

PEOPLE

COMM.CHANNEL

UserUpdated{

Id: 100,Email: ‘mynewemail@gmail.com’SomeField: ‘some_value’

}

NOTIFICATION

COMM. CHANNEL

NOTIFICATION

RECIPIENTS

Messages order

Versioning

PEOPLE

COMM.CHANNEL

UserUpdated{

Id: 100,Email: ‘mynewemail@gmail.com’,SomeField: ‘some_value’,Version: 3

}

COMM. CHANNEL

NOTIFICATION

Recipient

Id : 100Email : ‘oldmail@gmail.com’Version: 1

PEOPLE

COMM.CHANNEL

UserUpdated{

Id: 100,Email: ‘mynewemail@gmail.com’,SomeField: ‘some_value’,Version: 2

}

COMM. CHANNEL

NOTIFICATION

Recipient

Id : 100Email : ‘email@gmail.com’Version: 3

Idempotency

Ability to replay messages

Events publisher

PEOPLE PEOPLEEVENTS

PEOPLE EVENT PUBLISHER

COMMUNICATION CHANNEL

Testing

Our infrastructure

• RabbitMQ

• Reactive Extensions

• JSON as message format

Business monitoring

Big picture

Thanks.

@mimmozzo domenico.musto@gmail.com