Why Service Oriented

Architecture? Sean Farmar

@farmar

The Evolution

•Small monolith

•Success == growth == features ++

•Team Scaling

•Maintenance nightmare == high risk

•So we end up with …

Big Ball of Mud

So I went to my master

Solve the problem you want?

•Coupling your problem is

•SOA your solution is

Why SOA?

•SOA's tenets are about reducing coupling.

•Afferent (dependents)

•Efferent (depend on)

•Temporal (time, RPC)

•Spatial (deployment, endpoint address)

•Platform (protocols, .Net Remoting)

Coupling

Coupling: SolutionsPlatform:

•XML on the wire.

•XSD (schema) describing XML structure

•Use standards based transfer protocol like http

•Standards based description of message flow

•WSDL (only supports request/response)

•SSDL(supports richer semantics)

Coupling: Solutions

Temporal:

•Asynchronous messaging

•Publish Subscribe

Coupling: Solutions

Spatial:

•Application level code should not need to know where cooperating services are on the network

In practice

In practice• Vertical Slicing

•Using asynchronous messaging

•Using publish subscribe

• Business domain decomposition

• Explicit intentions [naming, context]

• Single Responsibility

• Command Query Separation

• “Clean Code” (Uncle Bob)

n-tier architecture

Vertical Slicing

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Summary

•SOA

•NServiceBus

•Particular.net

•You can do it

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Q&A

Thank You!Sean Farmartwitter: @farmarParticular.net