Consumer Driven Contracts and Your Microservice Architecture @ Warsaw JUG

1 © 2016 Pivotal

Consumer Driven Contracts and Your Microservice Architecture

Marcin Grzejszczak, @mgrzejszczak

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Spring Cloud developer at PivotalWorking mostly on

● Spring Cloud Sleuth ● Spring Cloud Contract● Spring Cloud Pipelines

About me

Twitter: @mgrzejszczakBlog: http://toomuchcoding.com

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Introduction

Demo

Summary

Agenda

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What we will NOT be talking about?

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What we will NOT be talking about?

THE IDEA OF SPRING CLOUD CONTRACT IS NOT TO

INTRODUCE UNNECESSARY COUPLING OR REPLICATE OLD

MISTAKES

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Introduction

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Introduction

What problems are we trying to solve?

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Introduction

Typical situation

HTTP

CONSUMER PRODUCER

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Introduction

How to write a test for it?

HTTP

CONSUMER PRODUCER

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Introduction

How to write a test for it?

HTTP

CONSUMER PRODUCER

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Introduction

Stub validity & reusability

WE’RE ON THE CONSUMER SIDE!!

CONSUMER OWNS THE STUB DEFINITIONS

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Introduction

Stub validity & reusability

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Introduction

Let’s assume that we’re introducing a new endpoint...

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Introduction

Stub validity & reusability

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Introduction

So now what?

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Introduction

Ooops...

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Introduction

What went wrong?

HTTP

CONSUMER PRODUCER

TEST

OK

HTTP

CONSUMER PRODUCER

REALITY

WAT?!

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Introduction

Another example with messaging

CONSUMERPRODUCER

TEST

PRODUCER CONSUMER

REALITY

topic: bar topic: foo

topic: bar

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Introduction

Stub validity & reusability

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Introduction

Nice API creation

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Introduction

Nice API creation - no cooperation results

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Introduction

Nice API creation - no cooperation results

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Demo

Potential answer

Spring Cloud Contract

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Demo

What are we going to code?

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Demo

What are we going to code?

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Introduction

What are we going to code?

I’m 22 give me a beer

CONSUMER PRODUCER

There you go!

Can he get the beer?

Yes!

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Introduction

What are we going to code?

I’m 17 give me a beer

CONSUMER PRODUCER

Get lost!

Can he get the beer?

No!

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Introduction

What are we going to code?

Someone’s 22. Check him out!

CONSUMERPRODUCER

Positive verification took place

Messaging

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Introduction

What are we going to code?

Someone’s 17. Check him out!

CONSUMERPRODUCER

Negative verification took place

Messaging

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Introduction

What are we going to code?

BLACK TERMINALBLACK IDE

CONSUMER

WHITE TERMINALWHITE IDE

PRODUCER

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Demo

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Summary

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Summary

PRODUCER CONSUMER

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Summary

PRODUCER

CONSUMER CLONES

PRODUCER

PRODUCERCLONE CONSUMER

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Summary

PRODUCER CONSUMERCONSUMER

CLONES PRODUCER

PRODUCERCLONE

INTERACTION

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Summary

PRODUCER CONSUMERPRODUCER

CLONE

INTERACTION

CONSUMER FILES A PR

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Summary

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Summary

PRODUCER

TAKES OVER THE PR

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Summary

PRODUCER

TAKES OVER THE PR

WRITES THE MISSING IMPLEMENTATION

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Summary

PRODUCER

TAKES OVER THE PR

WRITES THE MISSING IMPLEMENTATION

MERGES TO MASTERCI UPLOADS TO NEXUS /

ARTIFACTORY

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Summary

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Summary

CONSUMER

SWITCHES TO ONLINE MODE

DOWNLOADS STUBS OF COLLABORATORS DURING

BUILD PHASE

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Summary

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Summary

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I don’t want to keep my contracts with the producer

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Demo

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Common repo with contracts - consumer

PRODUCER CONSUMER

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Common repo with contracts - consumer

PRODUCER CONSUMER

REPO WITH CONTRACTS

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Common repo with contracts - consumer

PRODUCER CONSUMER

REPO WITH CONTRACTS

GIT CLONE

CLONED REPO WITH

CONTRACTS

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Common repo with contracts - consumer

PRODUCER CONSUMER

REPO WITH CONTRACTS

GIT CLONE

CLONED REPO WITH

CONTRACTS

INTERACTION

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Common repo with contracts - consumer

PRODUCER CONSUMER

REPO WITH CONTRACTS

CLONED REPO WITH

CONTRACTS

PR

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Common repo with contracts - producer

PRODUCER CONSUMER

REPO WITH CONTRACTS

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Common repo with contracts - producer

PRODUCER CONSUMER

REPO WITH CONTRACTS

CLONED REPO WITH

CONTRACTS

PRODUCER

TAKES

OVER PR

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WRITES THE MISSING IMPLEMENTATION

Common repo with contracts - producer

PRODUCER CONSUMER

REPO WITH CONTRACTS

CLONED REPO WITH

CONTRACTS

PRODUCER

TAKES

OVER PR

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WRITES THE MISSING IMPLEMENTATION

Common repo with contracts - producer

PRODUCER CONSUMER

REPO WITH CONTRACTS

CLONED REPO WITH

CONTRACTS

MERGE PR

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WRITES THE MISSING IMPLEMENTATION

Common repo with contracts - producer

PRODUCER CONSUMER

REPO WITH CONTRACTS

CI UPLOADS TO NEXUS

/ ARTIFACTORY

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I don’t want to keep my contracts with the producer

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I don’t want to write any scripts!

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Introduction

Don’t worry! You can use Spring Cloud Contract WireMock with Rest Docs!!

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Demo

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Summary

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Summary

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QUESTIONS

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Learn More. Stay Connected.

▪ Read the docs

▪ Check the samples

▪ Talk to us on Gitter

Twitter: twitter.com/springcentral

YouTube: spring.io/video

LinkedIn: spring.io/linkedin

Google Plus: spring.io/gplus

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mgrzejszczak