Antifragile Software. Building Adaptable Software with Microservices

153 Pages·2016·9.68 MB·English

by  Russ Miles

Antifragile Software
Building Adaptable Software with
Microservices
Russ Miles
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Thisversionwaspublishedon2016-02-08
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©2013-2016RussMiles
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Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
GrabbingtheCode . . . . . . . . . . . . . . . . . . 2
Option1:BrowsethecodeonGitHub . . . . . . . . 3
Option2:DownloadtheCodeasZipFiles . . . . . . 3
AboutTheAuthor . . . . . . . . . . . . . . . . . . . 4
Acknowledgements . . . . . . . . . . . . . . . . . . 6
Introduction . . . . . . . . . . . . . . . . . . . . . . . . 7
WhatthisbookisNOTabout . . . . . . . . . . . . . 8
PhilosophicalUnderpinnings . . . . . . . . . . . . . 11
Axioms . . . . . . . . . . . . . . . . . . . . . . . . . 12
Whatarewereallydealingwith,then? . . . . . . . 20
ANodTowardsOver-Production . . . . . . . . . . . 22
BookI-ThePhilosophyofChangeinSoftware . . . . 25
TheParableofTheElephantintheStandup . . . . . . 26
Grief,Anger,Disbelief… . . . . . . . . . . . . . . . 28
…Guilt… . . . . . . . . . . . . . . . . . . . . . . . . 29
TheElephantintheStandup . . . . . . . . . . . . . 29
EverybodyLies . . . . . . . . . . . . . . . . . . . . 30
Lie1:It’saBigChangereally… . . . . . . . . . . . . 31
CONTENTS
Lie2:TheExtended-Holidayof‘Refactoring’ . . . . 32
RefactoringshouldbeQuick,Easy andConstant . . 33
Lie3:Sorry,you’reinTechnicalDebt… . . . . . . . 34
TechnicalDebtisforreal . . . . . . . . . . . . . . . 35
The Elephant in the Standup is not Technical Debt,
nor Refactoring . . . . . . . . . . . . . . . . . 35
SoftwareArchitectureisPhilosophy . . . . . . . . . . 36
WhatisSoftwareArchitectureandDesign? . . . . . 36
WhatisPhilosophy? . . . . . . . . . . . . . . . . . 37
SoftwareArchitectureAbides . . . . . . . . . . . . 39
PlatoandtheWaterfall . . . . . . . . . . . . . . . . 40
Agility andFortuna . . . . . . . . . . . . . . . . . . 42
ArchitectureneedstoembraceFortuna . . . . . . . 44
StressorsonSoftware . . . . . . . . . . . . . . . . . . . 46
AntifragilityinSoftware . . . . . . . . . . . . . . . . . 50
Change,AdaptionandAnti-fragility . . . . . . . . . 51
TheChangeStressorandtheAdaptionResponse . . 51
DefiningAntifragileSoftwareSystems. . . . . . . . 58
The Need for Antifragility in Software: Enabling
Innovation. . . . . . . . . . . . . . . . . . . . 59
EmergenceandAntifragility . . . . . . . . . . . . . 60
AntifragilityisintheRelationships . . . . . . . . . 61
LoveisAntifragile,aninterlude . . . . . . . . . . . 62
RelationshipsbetweenPartsaretheKey . . . . . . . 63
SimplicityinSoftware,Defined . . . . . . . . . . . . . 64
SimplicityisObjective . . . . . . . . . . . . . . . . . 65
TheSimplicityContinuum . . . . . . . . . . . . . . 65
Essential &Accidental Complexity. . . . . . . . . . 67
CONTENTS
Whydoweintroduceaccidentalcomplexity? . . . . 67
SimpleArchitecture&Design? . . . . . . . . . . . . 68
Microservice-based Architectures for Antifragility &
Simplicity . . . . . . . . . . . . . . . . . . . . . . . 69
EmbracingChangewithMicroservices . . . . . . . 70
EmbracingorevenThrivingonChangeintheLinks
betweenMicroservices . . . . . . . . . . . . . 71
Lies,DamnedLies,andLiesaboutMicroservices . . 73
ThePayback:SpeedofInnovation . . . . . . . . . . . . 75
Whatisinnovation? . . . . . . . . . . . . . . . . . . 75
EnablingInnovation . . . . . . . . . . . . . . . . . . 76
TechnicalInnovationStressors . . . . . . . . . . . . 78
OntheOriginofServices… . . . . . . . . . . . . . . 79
Antifragile Systems of Microservices are an Engine
forInnovation . . . . . . . . . . . . . . . . . . 80
Remember&Apply . . . . . . . . . . . . . . . . . . . . 82
Book II - Architecture, Design & Implementation for
Antifragility . . . . . . . . . . . . . . . . . . . . . . 84
SkinintheGame . . . . . . . . . . . . . . . . . . . . . 85
Ethics:DoIt,RiskIt . . . . . . . . . . . . . . . . . . 86
Show,Share,MakeMistakes,LearnandImprove . . 88
OnBeingCritical . . . . . . . . . . . . . . . . . . . 89
Fear,Loathing&PromiseinUncertainty-Ville . . . . 90
Idea1:AnOpenCloudIndex . . . . . . . . . . . . . 93
Phone,OrHaveaDrinkwith,AFriend . . . . . . . 94
UbiquitousLanguage&DomainObjects? . . . . . . 95
CONTENTS
TheIllsoftheLayeredArchitecture . . . . . . . . . 96
The Domain Objects at the Centre of the Universe
Anti-Pattern . . . . . . . . . . . . . . . . . . . 100
NoonewantstochangetheDomainObjects… . . . . 103
Promiscous and Incorrect Domain Objects and the
RippleEffect . . . . . . . . . . . . . . . . . . . 104
NottheThings,theThingsthathappen . . . . . . . 105
Events,aBetterUbiquitousLanguage . . . . . . . . 106
Past,UnchangeableFacts . . . . . . . . . . . . . . . 107
UnderstandingEvents-90%Accountant,10%RockStar108
EventStreams . . . . . . . . . . . . . . . . . . . . . 109
Comprehending Event Streams with Projections &
Aggregates . . . . . . . . . . . . . . . . . . . 111
AnsweringtheQuestionwithViews . . . . . . . . . 114
Fast andSlowFlows . . . . . . . . . . . . . . . . . . 116
Lambdas!? . . . . . . . . . . . . . . . . . . . . . . . 117
WhatnoREST yet? . . . . . . . . . . . . . . . . . . 119
SoftwareAntifragilitypatternswithStressors . . . . 120
Time…toBuild . . . . . . . . . . . . . . . . . . . . . . 122
TheProblemofBelongingtoTomorrow . . . . . . . 123
ReducingthefearofBigDecisions . . . . . . . . . . 125
EatinganElephantwiththeLifePreserver . . . . . . 128
ATaleofThreeTeams . . . . . . . . . . . . . . . . 129
Backto“SkinintheGame” . . . . . . . . . . . . . . 130
Whatistherightapproachtobuildingasystem? . . 131
TheProcessandTool:TheLifePreserver . . . . . . . 132
DoingO.R.E.:Organise,Reduce&Encapsulate . . . 133
The Life Preserver Process: Asking and Answering
Questions . . . . . . . . . . . . . . . . . . . . 134
CONTENTS
JustEnoughDesign . . . . . . . . . . . . . . . . . . 134
Wheredoesmycomponentgo? . . . . . . . . . . . 134
Whatshouldmycomponentdo? . . . . . . . . . . . 134
GroupTogetherthatChangeTogether . . . . . . . . 134
WhenshouldIsplitmycomponent? . . . . . . . . . 134
DiscovertheDomain . . . . . . . . . . . . . . . . . 134
HowshouldmyComponentsCommunicate?Design
Events . . . . . . . . . . . . . . . . . . . . . . 135
How should my Events be transmitted? Design Dis-
patch. . . . . . . . . . . . . . . . . . . . . . . 135
HowshouldmyEventsbeEncoded?DesignPayload 135
ThinkingStressors . . . . . . . . . . . . . . . . . . . 137
CreatingStressors . . . . . . . . . . . . . . . . . . . 137
ConsiderCircuitBreakers . . . . . . . . . . . . . . . 137
ConsiderBulkheads . . . . . . . . . . . . . . . . . . 137
12-FactorServices? . . . . . . . . . . . . . . . . . . 137
ConsiderTechnologiesEarly . . . . . . . . . . . . . 137
BoundedContexts,Boundaries&FractureLineswith
TectonicPlates . . . . . . . . . . . . . . . . . 137
What‘could’change . . . . . . . . . . . . . . . . . 137
Naiveisok,atfirst . . . . . . . . . . . . . . . . . . 137
HavingaConversationaboutChange . . . . . . . . 137
SeeingInter-Plateand-ComponentCommunication 137
FrictionattheFaultLines . . . . . . . . . . . . . . . 137
FocusonwheretheFrictionisGreatest . . . . . . . 137
TestingyourInter-PlateChangeCoupling . . . . . . 138
TheDangersofInappropriateInter-PlateIntimacy . 138
FlowsacrosstheLifePreserver . . . . . . . . . . . . 138
ContinuousRefinement:EmergentDesign . . . . . . 138
ScalingLifePreservers . . . . . . . . . . . . . . . . 138
BigPayback:Objectivitity . . . . . . . . . . . . . . . 138
CONTENTS
ManifestNOforAntifragileSoftware . . . . . . . . . . 139
ChangeandOssification . . . . . . . . . . . . . . . 139
EvilManifestosofYearsPast . . . . . . . . . . . . . 139
WhyaManifestoatall? . . . . . . . . . . . . . . . . 139
DodgingtheBullet . . . . . . . . . . . . . . . . . . 139
WhyMicroservicesarenotjustSOA . . . . . . . . . 140
Remember&Apply . . . . . . . . . . . . . . . . . . . . 141
SuggestedFurtherReading . . . . . . . . . . . . . . . . 142
CONTENTS 1
ForMali
ForAshton
ForSiobhán
FromRuss:Ihopeyourlearningjourneysneverend