基于 DDD、EventSourcing 的现代响应式 CQRS 架构微服务开发框架

领域驱动 | 事件驱动 | 测试驱动 | 声明式设计 ｜ 响应式编程 ｜ 命令查询职责分离 ｜ 事件源

更新内容 🎉 🎉 🎉

• 特性: Wow 编译器(wow-compiler)支持检测聚合模型超类静态租户ID
• 特性: 新增 RecordEventFunctionErrorHandler 支持记录事件函数处理异常，以支持更友好的事件补偿
• 特性: AggregateVerifier 支持尽早检测状态聚合模型序列化问题
• 特性: CommandHandlerFunction 支持从 Http.Header 中获取聚合ID

架构图

事件源

可观测性

Spring WebFlux 集成

自动注册 命令 路由处理函数 (HandlerFunction) ，开发人员仅需编写领域模型，即可完成服务开发。

测试套件：80%+ 的测试覆盖率轻而易举

Given -> When -> Expect .

前置条件

• 理解 领域驱动设计：《实现领域驱动设计》、《领域驱动设计：软件核心复杂性应对之道》
• 理解 命令查询职责分离（CQRS）
• 理解 事件源架构
• 理解 响应式编程

特性

•  Aggregate Modeling
  •  Single Class
  •  Inheritance Pattern
  •  Aggregation Pattern
•  Saga Modeling
  •  StatelessSaga
•  Test Suite
  •  兼容性测试规范（TCK）
  •  AggregateVerifier
  •  SagaVerifier
•  EventSourcing
  • EventStore
    •  MongoDB (Recommend)
    •  R2dbc
      •  Database Sharding
      •  Table Sharding
    •  Redis
  • Snapshot
    •  MongoDB
    •  R2dbc
      •  Database Sharding
      •  Table Sharding
    •  ElasticSearch
    •  Redis (Recommend)
•  命令等待策略（WaitStrategy）
  •  SENT : 命令发送成功后发送完成信号
  •  PROCESSED : 命令处理完成后发送完成信号
  •  SNAPSHOT : 快照生成完成后发送完成信号
  •  PROJECTED : 命令产生的事件被投影后发送完成信号
•  CommandBus
  •  InMemoryCommandBus
  •  KafkaCommandBus (Recommend)
  •  RedisCommandBus
  •  LocalFirstCommandBus
•  DomainEventBus
  •  InMemoryDomainEventBus
  •  KafkaDomainEventBus (Recommend)
  •  RedisDomainEventBus
  •  LocalFirstDomainEventBus
•  StateEventBus
  •  InMemoryStateEventBus
  •  KafkaStateEventBus (Recommend)
  •  RedisStateEventBus
  •  LocalFirstStateEventBus
•  Spring 集成
  •  Spring Boot Auto Configuration
  •  Automatically register CommandAggregate to RouterFunction
•  可观测性
  •  OpenTelemetry
•  OpenApi
•  WowMetadata Generator
  •  wow-compiler

Example

Example

测试套件

80%+ 的测试覆盖率轻而易举。

Given -> When -> Expect .

internal class OrderTest {

    companion object {
        val SHIPPING_ADDRESS = ShippingAddress("China", "ShangHai", "ShangHai", "HuangPu", "001")
    }

    private fun mockCreateOrder(): VerifiedStage<OrderState> {
        val tenantId = GlobalIdGenerator.generateAsString()
        val customerId = GlobalIdGenerator.generateAsString()

        val orderItem = OrderItem(
            GlobalIdGenerator.generateAsString(),
            GlobalIdGenerator.generateAsString(),
            BigDecimal.valueOf(10),
            10
        )
        val orderItems = listOf(orderItem)
        val inventoryService = object : InventoryService {
            override fun getInventory(productId: String): Mono<Int> {
                return orderItems.toFlux().filter { it.productId == productId }.map { it.quantity }.last()
            }
        }
        val pricingService = object : PricingService {
            override fun getProductPrice(productId: String): Mono<BigDecimal> {
                return orderItems.toFlux().filter { it.productId == productId }.map { it.price }.last()
            }
        }
        return aggregateVerifier<Order, OrderState>(tenantId = tenantId)
            .inject(DefaultCreateOrderSpec(inventoryService, pricingService))
            .given()
            .`when`(CreateOrder(customerId, orderItems, SHIPPING_ADDRESS))
            .expectEventCount(1)
            .expectEventType(OrderCreated::class.java)
            .expectStateAggregate {
                assertThat(it.aggregateId.tenantId, equalTo(tenantId))
            }
            .expectState {
                assertThat(it.id, notNullValue())
                assertThat(it.customerId, equalTo(customerId))
                assertThat(it.address, equalTo(SHIPPING_ADDRESS))
                assertThat(it.items, equalTo(orderItems))
                assertThat(it.status, equalTo(OrderStatus.CREATED))
            }
            .verify()
    }

    /** * 创建订单 */
    @Test
    fun createOrder() {
        mockCreateOrder()
    }

    /** * 创建订单-库存不足 */
    @Test
    fun createOrderWhenInventoryShortage() {
        val customerId = GlobalIdGenerator.generateAsString()
        val orderItem = OrderItem(
            GlobalIdGenerator.generateAsString(),
            GlobalIdGenerator.generateAsString(),
            BigDecimal.valueOf(10),
            10
        )
        val orderItems = listOf(orderItem)
        val inventoryService = object : InventoryService {
            override fun getInventory(productId: String): Mono<Int> {
                return orderItems.toFlux().filter { it.productId == productId }
                    /* * 模拟库存不足 */
                    .map { it.quantity - 1 }.last()
            }
        }
        val pricingService = object : PricingService {
            override fun getProductPrice(productId: String): Mono<BigDecimal> {
                return orderItems.toFlux().filter { it.productId == productId }.map { it.price }.last()
            }
        }

        aggregateVerifier<Order, OrderState>()
            .inject(DefaultCreateOrderSpec(inventoryService, pricingService))
            .given()
            .`when`(CreateOrder(customerId, orderItems, SHIPPING_ADDRESS))
            /* * 期望：库存不足异常. */
            .expectErrorType(InventoryShortageException::class.java)
            .expectStateAggregate {
                /* * 该聚合对象处于未初始化状态，即该聚合未创建成功. */
                assertThat(it.initialized, equalTo(false))
            }.verify()
    }

    /** * 创建订单-下单价格与当前价格不一致 */
    @Test
    fun createOrderWhenPriceInconsistency() {
        val customerId = GlobalIdGenerator.generateAsString()
        val orderItem = OrderItem(
            GlobalIdGenerator.generateAsString(),
            GlobalIdGenerator.generateAsString(),
            BigDecimal.valueOf(10),
            10
        )
        val orderItems = listOf(orderItem)
        val inventoryService = object : InventoryService {
            override fun getInventory(productId: String): Mono<Int> {
                return orderItems.toFlux().filter { it.productId == productId }.map { it.quantity }.last()
            }
        }
        val pricingService = object : PricingService {
            override fun getProductPrice(productId: String): Mono<BigDecimal> {
                return orderItems.toFlux().filter { it.productId == productId }
                    /* * 模拟下单价格、商品定价不一致 */
                    .map { it.price.plus(BigDecimal.valueOf(1)) }.last()
            }
        }
        aggregateVerifier<Order, OrderState>()
            .inject(DefaultCreateOrderSpec(inventoryService, pricingService))
            .given()
            .`when`(CreateOrder(customerId, orderItems, SHIPPING_ADDRESS))
            /* * 期望：价格不一致异常. */
            .expectErrorType(PriceInconsistencyException::class.java).verify()
    }

    private fun mockPayOrder(): VerifiedStage<OrderState> {
        val verifiedStageAfterCreateOrder = mockCreateOrder()
        val previousState = verifiedStageAfterCreateOrder.stateRoot
        val payOrder = PayOrder(
            previousState.id,
            GlobalIdGenerator.generateAsString(),
            previousState.totalAmount
        )

        return verifiedStageAfterCreateOrder
            .then()
            .given()
            /* * 2. 当接收到命令 */
            .`when`(payOrder)
            /* * 3.1 期望将会产生1个事件 */
            .expectEventCount(1)
            /* * 3.2 期望将会产生一个 OrderPaid 事件 (3.1 可以不需要) */
            .expectEventType(OrderPaid::class.java)
            /* * 3.3 期望产生的事件状态 */
            .expectEventBody<OrderPaid> {
                assertThat(it.amount, equalTo(payOrder.amount))
            }
            /* * 4. 期望当前聚合状态 */
            .expectState {
                assertThat(it.address, equalTo(SHIPPING_ADDRESS))
                assertThat(it.paidAmount, equalTo(payOrder.amount))
                assertThat(it.status, equalTo(OrderStatus.PAID))
            }
            /* * 完成测试编排后，验证期望. */
            .verify()
    }

    /** * 支付订单 */
    @Test
    fun payOrder() {
        mockPayOrder()
    }

    /** * 支付订单-超付 */
    @Test
    fun payOrderWhenOverPay() {
        val verifiedStageAfterCreateOrder = mockCreateOrder()
        val previousState = verifiedStageAfterCreateOrder.stateRoot
        val payOrder = PayOrder(
            previousState.id,
            GlobalIdGenerator.generateAsString(),
            previousState.totalAmount.plus(
                BigDecimal.valueOf(1)
            )
        )
        verifiedStageAfterCreateOrder
            .then()
            .given()
            /* * 2. 处理 PayOrder 命令 */
            .`when`(payOrder)
            /* * 3.1 期望将会产生俩个事件分别是： OrderPaid、OrderOverPaid */
            .expectEventType(OrderPaid::class.java, OrderOverPaid::class.java)
            /* * 3.2 期望产生的事件状态 */
            .expectEventStream {
                val itr = it.iterator()
                /* * OrderPaid */
                val orderPaid = itr.next().body as OrderPaid
                assertThat(orderPaid.paid, equalTo(true))
                /* * OrderOverPaid */
                val orderOverPaid = itr.next().body as OrderOverPaid
                assertThat(
                    orderOverPaid.overPay,
                    equalTo(payOrder.amount.minus(previousState.totalAmount))
                )
            }
            /* * 4. 期望当前聚合状态 */
            .expectState {
                assertThat(it.paidAmount, equalTo(previousState.totalAmount))
                assertThat(it.status, equalTo(OrderStatus.PAID))
            }
            .verify()
    }

    /** * 发货 */
    @Test
    fun ship() {
        val verifiedStageAfterPayOrder = mockPayOrder()
        val shipOrder = ShipOrder(verifiedStageAfterPayOrder.stateRoot.id)
        verifiedStageAfterPayOrder
            .then().given()
            .`when`(shipOrder)
            .expectEventType(OrderShipped::class.java)
            /* * 4. 期望当前聚合状态 */
            .expectState {
                assertThat(it.status, equalTo(OrderStatus.SHIPPED))
            }
            .verify()
    }

    @Test
    fun shipGivenUnpaid() {
        val verifiedStageAfterCreateOrder = mockCreateOrder()
        val shipOrder = ShipOrder(verifiedStageAfterCreateOrder.stateRoot.id)
        verifiedStageAfterCreateOrder.then().given()
            .`when`(shipOrder)
            .expectErrorType(IllegalStateException::class.java)
            .expectState {
                /* * 验证聚合状态[未]发生变更. */
                assertThat(it.paidAmount, equalTo(BigDecimal.ZERO))
                assertThat(it.status, equalTo(OrderStatus.CREATED))
            }
            .verify()
    }

    private fun mockDeleteOrder(): VerifiedStage<OrderState> {
        val verifiedStageAfterCreateOrder = mockCreateOrder()
        return verifiedStageAfterCreateOrder.then().given()
            .`when`(DeleteAggregate)
            .expectEventType(AggregateDeleted::class.java)
            .expectStateAggregate {
                assertThat(it.deleted, equalTo(true))
            }
            .verify()
    }

    @Test
    fun deleteOrder() {
        mockDeleteOrder()
    }

    @Test
    fun deleteGivenDeleted() {
        val verifiedStageAfterDelete = mockDeleteOrder()
        verifiedStageAfterDelete.then().given()
            .`when`(DeleteAggregate)
            .expectErrorType(IllegalAccessDeletedAggregateException::class.java)
            .expectError<IllegalAccessDeletedAggregateException> {
                assertThat(it.aggregateId, equalTo(verifiedStageAfterDelete.stateAggregate.aggregateId))
            }.expectStateAggregate {
                assertThat(it.deleted, equalTo(true))
            }
            .verify()
    }
}

设计

聚合建模

Single Class	Inheritance Pattern	Aggregation Pattern

加载聚合

聚合状态流

发送命令

命令与事件流

Saga - OrderProcessManager (Demo)