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GoNamingandStructure
JaapGroeneveld-jGroeneveld.de

2.
Agenda
AverybriefintroductiontoGo
NamingConventions
ApplicationStructure
Literature
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3.
Averybriefintroduction
Goisaminimallanguage
Goisacompiledlanguage
Gohasadedicatedconcurrencyconcept
(Goroutines,channels,select)
Goisnotobjectoriented
Godoesnotuseexceptionsforerrors
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4.
Naming-Variables
UsecamelCasenotsnake_case
Singlelettervariablesforindexes for i:=0; i < 10; i++ {}
Shortanddescriptivenames
var count int
var customer Customer
Usethescopeofthevariableasyourguide.Thefartherawayfromdeclarationyou
useit,thelongerandclearerthenameshouldbe
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5.
Abbreviations
Repeatedlettersforcollections var tt []*Thing (prefer things whenscopeis
bigger)
Singleletterinsideloop for i, t := range tt {} (preferthingwhenscopeis
bigger)
Commonabbreviationsareused decodeJSON , customer.ID
Someabbrevationsarecommonthroughoutgocode
r *http.Request , w io.Writer , w http.ResponseWriter , err error , ...
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6.
Naming-Interfaces
Nameoftheinterfaceshoulddescribeitsfunctionality
CustomerStore
Ifinterfacehasonlyonefunction,append"-er"
type Stringer interface{
String() string
}
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7.
Naming-Packages
Packagesnamesdescribetheirpurpose
Itʼsveryeasytoseewhatapackagedoesbylookingatthename
Namesaregenerallyshort
archive cmd crypto errors math
Whennecessary,useadescriptiveparentpackageandseveralchildren
implementingthefunctionality
encoding/base64 encoding/csv encoding/json
Avoidcatchallpackages util helpers
Avoidapackage-levelfunctionnamethatrepeatsthepackagename
log.Info() vs log.LogInfo()
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8.
Naming-Files
Insideapackageseparatecodeintologicalconcerns.
Ifthepackagedealswithmultipletypes,keepthelogicforeachtypeinitsownsource
file:
package: db
orders.go
suppliers.go
products.go
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9.
ApplicationStructure
Applicationpackageorganizationhasahugeimpactonthetestabilityand
functionalityofyoursystem
Whenwritinganapplicationyourgoalshouldbetowritecodethatiseasyto
understand,easytorefactor,andeasyforsomeoneelsetomaintain.
Thereisnotoneapplicationstructure.
Oneidea:Separatedomain,servicesanddependencies(adapters).benbjohnson
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10.
ApplicationStructureexample
Dependenciesandservicesshouldbeinseparatepackagesforeasiertesting db ,
someapi ...
Domaintypesandinterfacestooperateonthemareinroot
Dependenciesandservicesimplementdomaininterfaces
Binaries(CLI/Server...)areinseparatepackagesasseparatemains cmd andglue
domainandservicestogether.
Thisincreasescohesion,reducescouplingandpreventscirculardependencies
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ApplicationStructureexample
- myapp
- cmd
- cli
- main.go // glues services and dependencies together for the cli
- server
- main.go // glues services and dependencies together for the server
- api // contains our api (using domain interfaces and models)
- db // dependency to connect and manage data in db
- someapi // dependency to connect to "someapi"
- users // contains services for users
- users.go // domain models and interfaces regarding users
- ... // further domain models and interfaces
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13.
GeneralGoliterature
EffectiveGoTheguide
GobyExamplehands-onintroductionusingannotatedexampleprograms
Gogo-toguideGotchas,cheatsheets,blueprintsetc
Learngowithtests
awesome-golistoflibraries
go-kitexampleprojectsformicroservices
UberStyleguide
APIDesignBestPractices
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