The lean development stackAdrien LAUER

SeedStack

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HistoryProject started late 2012

10+ years experience of frameworksCustomOpen-Source: mainly Spring

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GoalsBuild a common development stack

Shared across all business entitiesManufacturing / logistics / finance / sales / R&D / …

Being extensible

Enabling re-use

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OrganizationCore team at PSA Peugeot CitroënOther members at various locations

http://seedstack.orghttps://github.com/seedstackTwitter: @seedstackIRC: #seedstack on freenode

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Get presentation code samples at

https://github.com/adrienlauer/poss-samples

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Core valuesOpinion

A reference architecture for your apps

ModularitySingle responsibility principle

ExtensibilityOpen-Closed principle

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FoundationJavaSet of technologies to build backends

WebSet of technologies to build Web apps

BusinessDomain-Driven Design (DDD) approach

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FoundationJavaSet of technologies to build backends

WebSet of technologies to build Web apps

BusinessDomain-Driven Design (DDD) approach

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Java focusKernel + plugin architecture

One plugin per concernScalable

One global Guice injector

Unified configuration

Plugin discovery

Classpath scan Initialization

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Sample pluginpublic class MyPlugin extends AbstractPlugin { private final Set<Class<?>> annotatedClasses = new HashSet<>();

@Override public String name() { return "my-plugin"; }

@Override public Collection<ClasspathScanRequest> classpathScanRequests() { return classpathScanRequestBuilder().annotationType(Service.class).build(); }

@Override public InitState init(InitContext initContext) { annotatedClasses.addAll(initContext.scannedClassesByAnnotationClass().get(Service.class)); return InitState.INITIALIZED; }

@Override public Object nativeUnitModule() { return (Module) binder -> annotatedClasses.forEach(binder::bind); }}

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So we built the core…Contains the kernel

Provides basic featuresLaunchingConfigurationIoCService commandsDiagnostics

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Then we scaled up…10+ plugins

TestingSecurityTransactionsRESTMetrics / healthWeb…

Adding new technologies is quick and easy

All PSA requirements have been covered

50 satisfied projects over two years

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FoundationJavaSet of technologies to build REST backends

WebSet of technologies to build Web apps

BusinessDomain-Driven Design (DDD) approach

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Web focusLoader + fragments architecture

A fragment per concernComposable

Configure and initialize an SPA

Fragment download

Configuration computing Initialization

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Sample fragment{ "id": "demo", "name": "W20 POSS demo", "modules": { "user": "{demo}/modules/user" }, "i18n": { "en": [ "{demo}/i18n/messages-en.json" ], "fr": [ "{demo}/i18n/messages-fr.json" ] }, "routes": { "hello": { "template": "<div class=\"container\"><h1>Hello World!</h1></div>", "hidden": true }, "user": { "templateUrl": "{demo}/views/user.html", "controller": "UserController" } }}

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Main featuresBased on popular libraries

AngularJSRequireJS

Advanced enterprise features

Multi CSS frameworkBootstrapAngular material

Theming support2 Open-Source themes3 PSA proprietary themes

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FoundationJavaSet of technologies to build REST backends

WebSet of technologies to build Web apps

BusinessDomain-Driven Design (DDD) approach

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Level of involvement

Annotations

Interfaces

Base classes

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Building blocks

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Main featuresDDD semantic + injection

Easy-to-use default implementations

Smart DTO / domain mapping

Built-in identity generation strategies

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Sampleclass SaleServiceImpl implements SaleService { private final Repository<Seller, Long> sellerRepository; private final DomainRegistry domainRegistry;

@Inject public SaleServiceImpl(Repository<Seller, Long> sellerRepository, DomainRegistry domainRegistry) { this.sellerRepository = sellerRepository; this.domainRegistry = domainRegistry; }

@Override public void updateBonus(Order order, Long sellerId) { Seller seller = sellerRepository.load(sellerId); if (seller == null) { throw new IllegalArgumentException("Seller " + sellerId + " cannot be found"); }

BonusPolicy bonusPolicy = domainRegistry .getPolicy(BonusPolicy.class, seller.getBonusPolicy());

double orderBonus = bonusPolicy.computeBonus(order); seller.addToMonthlyBonus(orderBonus);

sellerRepository.save(seller); }}

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Extensibility20+ official add-ons

Audit, ElasticSearch, I18n, IO, JavaMail, JCache, JDBC, JMS, JPA, LDAP, MongoDB, Monitoring, Neo4J, Redis, Scheduling, Solr, Spring-bridge, Validation, W20-bridge, Web-Services, …

Open to third-partyhttp://seedstack.org/addons

PSA uses only 3 proprietary add-ons

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DistributionGlobal packaging of all modules

Each organization can roll its own distribution

Open-Source reference distribution released 3 times per year

16.4 16.7 16.11

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Thank you!Website: http://seedstack.orgGitHub: https://github.com/seedstackIRC: #seedstack on freenode

Contributions welcome!Pull requestsDocumentation fixesIssues