feat(event): Adding eventing lib (#3922)

build.gradle

@@ -40,7 +40,7 @@ buildscript {
     }
     classpath "com.netflix.nebula:nebula-kotlin-plugin:$kotlinVersion"
     classpath "org.junit.platform:junit-platform-gradle-plugin:${junitPlatformVersion}"
-
+    classpath "org.jetbrains.kotlin:kotlin-allopen:$kotlinVersion"
   }
 }
 
@@ -55,6 +55,7 @@ allprojects {
     apply plugin: 'java-library'
     apply plugin: 'groovy'
     apply plugin: 'nebula.kotlin'
+    apply plugin: "kotlin-allopen"
 
     sourceSets.main.java.srcDirs = []
     sourceSets.main.groovy.srcDirs += ["src/main/java"]

clouddriver-event/clouddriver-event.gradle

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+dependencies {
+  annotationProcessor "org.springframework.boot:spring-boot-autoconfigure-processor"
+
+  implementation "com.netflix.spinnaker.kork:kork-core"
+  implementation "com.netflix.spinnaker.kork:kork-exceptions"
+  implementation "com.google.guava:guava"
+  implementation "com.google.code.findbugs:jsr305"
+  implementation "org.springframework.boot:spring-boot-actuator"
+  implementation "com.fasterxml.jackson.module:jackson-module-kotlin"
+  implementation "javax.validation:validation-api"
+  implementation "org.hibernate.validator:hibernate-validator"
+
+  testImplementation "cglib:cglib-nodep"
+  testImplementation "org.objenesis:objenesis"
+  testImplementation "org.junit.platform:junit-platform-runner"
+  testImplementation "org.junit.jupiter:junit-jupiter-api"
+  testImplementation "org.springframework:spring-test"
+  testImplementation "org.springframework.boot:spring-boot-test"
+  testImplementation "org.assertj:assertj-core"
+  testImplementation "io.strikt:strikt-core"
+  testImplementation "dev.minutest:minutest"
+  testImplementation "io.mockk:mockk"
+
+  testRuntimeOnly "org.junit.platform:junit-platform-launcher"
+  testRuntimeOnly "org.junit.jupiter:junit-jupiter-engine"
+}

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/Aggregate.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event
+
+/**
+ * The identifiable collection of an event log.
+ *
+ * Aggregates are grouped by a [type] which should be unique for each domain entity, with unique
+ * [id] values therein. A [version] field is used to ensure business logic is operating on the
+ * latest event state; any modification to an [Aggregate] event log will increment this value.
+ * When an operation is attempted on an [version] which is not head, the event framework will
+ * reject the change.
+ */
+class Aggregate(
+  val type: String,
+  val id: String,
+  var version: Long
+) {
+  override fun equals(other: Any?): Boolean {
+    if (this === other) return true
+    if (javaClass != other?.javaClass) return false
+
+    other as Aggregate
+
+    if (type != other.type) return false
+    if (id != other.id) return false
+
+    return true
+  }
+
+  override fun hashCode(): Int {
+    var result = type.hashCode()
+    result = 31 * result + id.hashCode()
+    return result
+  }
+}

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/EventListener.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event
+
+/**
+ * Interface for subscribing to Spinnaker events.
+ *
+ * An implementation must be responsible for filtering out the events that it doesn't care about.
+ */
+interface EventListener {
+  fun onEvent(event: SpinnakerEvent)
+}

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/EventMetadata.kt

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event
+
+import java.time.Instant
+
+/**
+ * Metadata for a [SpinnakerEvent].
+ *
+ * @param sequence Auto-incrementing number for event ordering
+ * @param originatingVersion The aggregate version that originated this event
+ * @param timestamp The time at which the event was created
+ * @param serviceVersion The version of the service (clouddriver) that created the event
+ * @param provenance Where the event was generated and by what
+ */
+data class EventMetadata(
+  val sequence: Long,
+  val originatingVersion: Long,
+  val timestamp: Instant = Instant.now(),
+  val serviceVersion: String = "unknown",
+  val provenance: String = "unknown"
+)

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/EventPublisher.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event
+
+/**
+ * The event sourcing library event publisher.
+ *
+ * This library assumes that events are persisted first into a durable store and then propagated out
+ * to subscribers afterwards. There is no contract on immediacy or locality of events being delivered
+ * to subscribers: This is left entirely to the implementation.
+ */
+interface EventPublisher {
+  fun publish(event: SpinnakerEvent)
+}

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/SpinnakerEvent.kt

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event
+
+import com.fasterxml.jackson.annotation.JsonTypeInfo
+import java.util.UUID
+
+/**
+ * The base event class for the event sourcing library.
+ *
+ * @param aggregateType The type of aggregate the event is for
+ * @param aggregateId The id of the aggregate the event is for
+ * @property id A unique ID for the event. This value is for tracing, rather than loading events
+ * @property metadata Associated metadata about the event; not actually part of the "event proper"
+ */
+@JsonTypeInfo(
+  use = JsonTypeInfo.Id.NAME,
+  include = JsonTypeInfo.As.PROPERTY,
+  property = "spinEventType"
+)
+abstract class SpinnakerEvent(
+  val aggregateType: String,
+  val aggregateId: String
+) {
+  val id = UUID.randomUUID().toString()
+
+  lateinit var metadata: EventMetadata
+}

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/config/EventSourceAutoConfiguration.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event.config
+
+import org.springframework.context.annotation.Configuration
+import org.springframework.context.annotation.Import
+
+/**
+ * Auto-configures the event sourcing library.
+ */
+@Configuration
+@Import(MemoryEventRepositoryConfig::class)
+open class EventSourceAutoConfiguration

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/config/MemoryEventRepositoryConfig.kt

@@ -0,0 +1,100 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event.config
+
+import com.netflix.spectator.api.Registry
+import com.netflix.spinnaker.clouddriver.event.persistence.EventRepository
+import com.netflix.spinnaker.clouddriver.event.persistence.InMemoryEventRepository
+import org.slf4j.LoggerFactory
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty
+import org.springframework.boot.context.properties.ConfigurationProperties
+import org.springframework.boot.context.properties.EnableConfigurationProperties
+import org.springframework.context.ApplicationEventPublisher
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+import org.springframework.validation.annotation.Validated
+import java.time.Duration
+import javax.validation.Constraint
+import javax.validation.ConstraintValidator
+import javax.validation.ConstraintValidatorContext
+import javax.validation.constraints.Min
+import kotlin.reflect.KClass
+
+@Configuration
+@ConditionalOnProperty("spinnaker.clouddriver.eventing.memory-repository.enabled", matchIfMissing = true)
+@EnableConfigurationProperties(MemoryEventRepositoryConfigProperties::class)
+open class MemoryEventRepositoryConfig {
+
+  private val log by lazy { LoggerFactory.getLogger(javaClass) }
+
+  init {
+    log.info("Configuring EventRepository: InMemoryEventRepository")
+  }
+
+  @Bean
+  open fun eventRepository(
+    properties: MemoryEventRepositoryConfigProperties,
+    applicationEventPublisher: ApplicationEventPublisher,
+    registry: Registry
+  ): EventRepository =
+    InMemoryEventRepository(properties, applicationEventPublisher, registry)
+}
+
+@MemoryEventRepositoryConfigProperties.SpinValidated
+@ConfigurationProperties("spinnaker.clouddriver.eventing.memory-repository")
+open class MemoryEventRepositoryConfigProperties {
+  /**
+   * The max age of an [Aggregate]. One of this and [maxAggregatesCount] must be set.
+   */
+  @Min(
+    message = "Event repository aggregate age cannot be less than 24 hours.",
+    value = 60 * 60 * 24 * 1000
+  )
+  var maxAggregateAgeMs: Long? = Duration.ofHours(24).toMillis()
+
+  /**
+   * The max number of [Aggregate] objects. One of this and [maxAggregateAgeMs] must be set.
+   */
+  var maxAggregatesCount: Int? = null
+
+  @Validated
+  @Constraint(validatedBy = [Validator::class])
+  @Target(AnnotationTarget.CLASS)
+  annotation class SpinValidated(
+    val message: String = "Invalid event repository configuration",
+    val groups: Array<KClass<out Any>> = [],
+    val payload: Array<KClass<out Any>> = []
+  )
+
+  class Validator : ConstraintValidator<SpinValidated, MemoryEventRepositoryConfigProperties> {
+    override fun isValid(
+      value: MemoryEventRepositoryConfigProperties,
+      context: ConstraintValidatorContext
+    ): Boolean {
+      if (value.maxAggregateAgeMs != null && value.maxAggregatesCount != null) {
+        context.buildConstraintViolationWithTemplate("Only one of 'maxAggregateAgeMs' and 'maxAggregatesCount' can be defined")
+          .addConstraintViolation()
+        return false
+      }
+      if (value.maxAggregateAgeMs == null && value.maxAggregatesCount == null) {
+        context.buildConstraintViolationWithTemplate("One of 'maxAggregateAgeMs' and 'maxAggregatesCount' must be set")
+          .addConstraintViolation()
+        return false
+      }
+      return true
+    }
+  }
+}

clouddriver-event/src/main/kotlin/com/netflix/spinnaker/clouddriver/event/exceptions/AggregateChangeRejectedException.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2019 Netflix, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.netflix.spinnaker.clouddriver.event.exceptions
+
+import com.netflix.spinnaker.kork.exceptions.SystemException
+
+/**
+ * Thrown when one or more [SpinEvent] have been rejected from being committed to an [Aggregate].
+ *
+ * The process which originated the event must be retryable.
+ */
+class AggregateChangeRejectedException(message: String) : SystemException(message) {
+  override fun getRetryable() = true
+}