build: Migrate to flat project structure

This change updates the project structure to become flattened.
Previously, the simulator, frontend and API each lived into their own
directory.

With this change, all modules of the project live in the top-level
directory of the repository. This should improve discoverability of
modules of the project.

11 files changed, 0 insertions, 1016 deletions

diff --git a/simulator/opendc-serverless/opendc-serverless-service/build.gradle.kts b/simulator/opendc-serverless/opendc-serverless-service/build.gradle.kts
deleted file mode 100644
index f7e43aba..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/build.gradle.kts
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-description = "Serverless service for OpenDC"
-
-/* Build configuration */
-plugins {
-    `kotlin-library-conventions`
-    `testing-conventions`
-    `jacoco-conventions`
-}
-
-dependencies {
-    api(platform(project(":opendc-platform")))
-    api(project(":opendc-serverless:opendc-serverless-api"))
-    api(project(":opendc-telemetry:opendc-telemetry-api"))
-    implementation(project(":opendc-utils"))
-    implementation("io.github.microutils:kotlin-logging")
-
-    testImplementation(project(":opendc-simulator:opendc-simulator-core"))
-    testRuntimeOnly("org.apache.logging.log4j:log4j-slf4j-impl")
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/FunctionObject.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/FunctionObject.kt
deleted file mode 100644
index c12bbfe2..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/FunctionObject.kt
+++ /dev/null
@@ -1,139 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service
-
-import io.opentelemetry.api.metrics.BoundLongCounter
-import io.opentelemetry.api.metrics.BoundLongUpDownCounter
-import io.opentelemetry.api.metrics.BoundLongValueRecorder
-import io.opentelemetry.api.metrics.Meter
-import io.opentelemetry.api.metrics.common.Labels
-import org.opendc.serverless.service.deployer.FunctionInstance
-import java.util.*
-
-/**
- * An [FunctionObject] represents the service's view of a serverless function.
- */
-public class FunctionObject(
-    meter: Meter,
-    public val uid: UUID,
-    name: String,
-    allocatedMemory: Long,
-    labels: Map<String, String>,
-    meta: Map<String, Any>
-) : AutoCloseable {
-    /**
-     * The total amount of function invocations received by the function.
-     */
-    public val invocations: BoundLongCounter = meter.longCounterBuilder("function.invocations.total")
-        .setDescription("Number of function invocations")
-        .setUnit("1")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The amount of function invocations that could be handled directly.
-     */
-    public val timelyInvocations: BoundLongCounter = meter.longCounterBuilder("function.invocations.warm")
-        .setDescription("Number of function invocations handled directly")
-        .setUnit("1")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The amount of function invocations that were delayed due to function deployment.
-     */
-    public val delayedInvocations: BoundLongCounter = meter.longCounterBuilder("function.invocations.cold")
-        .setDescription("Number of function invocations that are delayed")
-        .setUnit("1")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The amount of function invocations that failed.
-     */
-    public val failedInvocations: BoundLongCounter = meter.longCounterBuilder("function.invocations.failed")
-        .setDescription("Number of function invocations that failed")
-        .setUnit("1")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The amount of instances for this function.
-     */
-    public val activeInstances: BoundLongUpDownCounter = meter.longUpDownCounterBuilder("function.instances.active")
-        .setDescription("Number of active function instances")
-        .setUnit("1")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The amount of idle instances for this function.
-     */
-    public val idleInstances: BoundLongUpDownCounter = meter.longUpDownCounterBuilder("function.instances.idle")
-        .setDescription("Number of idle function instances")
-        .setUnit("1")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The time that the function waited.
-     */
-    public val waitTime: BoundLongValueRecorder = meter.longValueRecorderBuilder("function.time.wait")
-        .setDescription("Time the function has to wait before being started")
-        .setUnit("ms")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The time that the function was running.
-     */
-    public val activeTime: BoundLongValueRecorder = meter.longValueRecorderBuilder("function.time.active")
-        .setDescription("Time the function was running")
-        .setUnit("ms")
-        .build()
-        .bind(Labels.of("function", uid.toString()))
-
-    /**
-     * The instances associated with this function.
-     */
-    public val instances: MutableList<FunctionInstance> = mutableListOf()
-
-    public var name: String = name
-        private set
-
-    public var memorySize: Long = allocatedMemory
-        private set
-
-    public val labels: MutableMap<String, String> = labels.toMutableMap()
-
-    public val meta: MutableMap<String, Any> = meta.toMutableMap()
-
-    override fun close() {
-        instances.forEach(FunctionInstance::close)
-        instances.clear()
-    }
-
-    override fun equals(other: Any?): Boolean = other is FunctionObject && uid == other.uid
-
-    override fun hashCode(): Int = uid.hashCode()
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/ServerlessService.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/ServerlessService.kt
deleted file mode 100644
index a791c815..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/ServerlessService.kt
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service
-
-import io.opentelemetry.api.metrics.Meter
-import org.opendc.serverless.api.ServerlessClient
-import org.opendc.serverless.service.deployer.FunctionDeployer
-import org.opendc.serverless.service.internal.ServerlessServiceImpl
-import org.opendc.serverless.service.router.RoutingPolicy
-import java.time.Clock
-import kotlin.coroutines.CoroutineContext
-
-/**
- * The [ServerlessService] hosts the API implementation of the OpenDC Serverless service.
- */
-public interface ServerlessService : AutoCloseable {
-    /**
-     * Create a new [ServerlessClient] to control the compute service.
-     */
-    public fun newClient(): ServerlessClient
-
-    /**
-     * Terminate the lifecycle of the serverless service, stopping all running function instances.
-     */
-    public override fun close()
-
-    public companion object {
-        /**
-         * Construct a new [ServerlessService] implementation.
-         *
-         * @param context The [CoroutineContext] to use in the service.
-         * @param clock The clock instance to use.
-         * @param meter The meter to report metrics to.
-         * @param deployer the [FunctionDeployer] to use for deploying function instances.
-         * @param routingPolicy The policy to route function invocations.
-         */
-        public operator fun invoke(
-            context: CoroutineContext,
-            clock: Clock,
-            meter: Meter,
-            deployer: FunctionDeployer,
-            routingPolicy: RoutingPolicy,
-        ): ServerlessService {
-            return ServerlessServiceImpl(context, clock, meter, deployer, routingPolicy)
-        }
-    }
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionDeployer.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionDeployer.kt
deleted file mode 100644
index 83592a68..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionDeployer.kt
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.deployer
-
-import org.opendc.serverless.service.FunctionObject
-
-/**
- * A [FunctionDeployer] is responsible for ensuring that an instance of an arbitrary function, a [FunctionInstance],
- * is deployed.
- *
- * The function deployer should combines the configuration stored in the function registry, the parameters supplied by
- * the requester, and other factors into a decision of how the function should be deployed, including how many and
- * what kind of resources it should receive.
- *
- * Though it decides how the function instance should be deployed, the deployment of the function instance itself is
- * delegated to the Resource Orchestration Layer.
- */
-public interface FunctionDeployer {
-    /**
-     * Deploy the specified [function].
-     */
-    public fun deploy(function: FunctionObject): FunctionInstance
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionInstance.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionInstance.kt
deleted file mode 100644
index d60648ea..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionInstance.kt
+++ /dev/null
@@ -1,55 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.deployer
-
-import org.opendc.serverless.service.FunctionObject
-
-/**
- * A [FunctionInstance] is a a self-contained worker—typically a container—capable of handling function executions.
- *
- * Multiple, concurrent function instances can exists for a single function, for scalability purposes.
- */
-public interface FunctionInstance : AutoCloseable {
-    /**
-     * The state of the instance.
-     */
-    public val state: FunctionInstanceState
-
-    /**
-     * The [FunctionObject] that is represented by this instance.
-     */
-    public val function: FunctionObject
-
-    /**
-     * Invoke the function instance.
-     *
-     * This method will suspend execution util the function instance has returned.
-     */
-    public suspend fun invoke()
-
-    /**
-     * Indicate to the resource manager that the instance is not needed anymore and may be cleaned up by the resource
-     * manager.
-     */
-    public override fun close()
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionInstanceState.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionInstanceState.kt
deleted file mode 100644
index 44ad80ee..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/deployer/FunctionInstanceState.kt
+++ /dev/null
@@ -1,53 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.deployer
-
-/**
- * This enumeration describes the states of a [FunctionInstance].
- */
-public enum class FunctionInstanceState {
-    /**
-     * The function instance is currently being provisioned.
-     */
-    Provisioning,
-
-    /**
-     * The function instance is idle and ready to execute.
-     */
-    Idle,
-
-    /**
-     * The function instance is executing.
-     */
-    Active,
-
-    /**
-     * The function instance is stopped but can be started.
-     */
-    Terminated,
-
-    /**
-     * The function instance is released and cannot be used anymore.
-     */
-    Deleted
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/internal/ServerlessFunctionImpl.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/internal/ServerlessFunctionImpl.kt
deleted file mode 100644
index 80b50e77..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/internal/ServerlessFunctionImpl.kt
+++ /dev/null
@@ -1,70 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.internal
-
-import org.opendc.serverless.api.ServerlessFunction
-import org.opendc.serverless.service.FunctionObject
-import java.util.*
-
-/**
- * A [ServerlessFunction] implementation that is passed to clients.
- */
-internal class ServerlessFunctionImpl(
-    private val service: ServerlessServiceImpl,
-    private val state: FunctionObject
-) : ServerlessFunction {
-    override val uid: UUID = state.uid
-
-    override var name: String = state.name
-        private set
-
-    override var memorySize: Long = state.memorySize
-        private set
-
-    override var labels: Map<String, String> = state.labels.toMap()
-        private set
-
-    override var meta: Map<String, Any> = state.meta.toMap()
-        private set
-
-    override suspend fun delete() {
-        service.delete(state)
-    }
-
-    override suspend fun invoke() {
-        service.invoke(state)
-    }
-
-    override suspend fun refresh() {
-        name = state.name
-        memorySize = state.memorySize
-        labels = state.labels
-        meta = state.meta
-    }
-
-    override fun equals(other: Any?): Boolean = other is ServerlessFunctionImpl && uid == other.uid
-
-    override fun hashCode(): Int = uid.hashCode()
-
-    override fun toString(): String = "ServerlessFunction[uid=$uid,name=$name]"
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/internal/ServerlessServiceImpl.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/internal/ServerlessServiceImpl.kt
deleted file mode 100644
index 515cb5fa..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/internal/ServerlessServiceImpl.kt
+++ /dev/null
@@ -1,290 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.internal
-
-import io.opentelemetry.api.metrics.Meter
-import kotlinx.coroutines.*
-import kotlinx.coroutines.intrinsics.startCoroutineCancellable
-import mu.KotlinLogging
-import org.opendc.serverless.api.ServerlessClient
-import org.opendc.serverless.api.ServerlessFunction
-import org.opendc.serverless.service.FunctionObject
-import org.opendc.serverless.service.ServerlessService
-import org.opendc.serverless.service.deployer.FunctionDeployer
-import org.opendc.serverless.service.deployer.FunctionInstance
-import org.opendc.serverless.service.router.RoutingPolicy
-import org.opendc.utils.TimerScheduler
-import java.lang.IllegalStateException
-import java.time.Clock
-import java.util.*
-import kotlin.coroutines.Continuation
-import kotlin.coroutines.CoroutineContext
-import kotlin.coroutines.resumeWithException
-
-/**
- * Implementation of the [ServerlessService] interface.
- *
- * This component acts as the function router from the SPEC RG Reference Architecture for FaaS and is responsible
- * for routing incoming requests or events to the correct [FunctionInstance]. If no [FunctionInstance] is available,
- * this component queues the events to await the deployment of new instances.
- */
-internal class ServerlessServiceImpl(
-    context: CoroutineContext,
-    private val clock: Clock,
-    private val meter: Meter,
-    private val deployer: FunctionDeployer,
-    private val routingPolicy: RoutingPolicy
-) : ServerlessService {
-    /**
-     * The [CoroutineScope] of the service bounded by the lifecycle of the service.
-     */
-    private val scope = CoroutineScope(context + Job())
-
-    /**
-     * The logger instance of this server.
-     */
-    private val logger = KotlinLogging.logger {}
-
-    /**
-     * The [TimerScheduler] to use for scheduling the scheduler cycles.
-     */
-    private val scheduler: TimerScheduler<Unit> = TimerScheduler(scope.coroutineContext, clock)
-
-    /**
-     * The [Random] instance used to generate unique identifiers for the objects.
-     */
-    private val random = Random(0)
-
-    /**
-     * The registered functions for this service.
-     */
-    private val functions = mutableMapOf<UUID, FunctionObject>()
-    private val functionsByName = mutableMapOf<String, FunctionObject>()
-
-    /**
-     * The queue of invocation requests.
-     */
-    private val queue = ArrayDeque<InvocationRequest>()
-
-    /**
-     * The total amount of function invocations received by the service.
-     */
-    private val _invocations = meter.longCounterBuilder("service.invocations.total")
-        .setDescription("Number of function invocations")
-        .setUnit("1")
-        .build()
-
-    /**
-     * The amount of function invocations that could be handled directly.
-     */
-    private val _timelyInvocations = meter.longCounterBuilder("service.invocations.warm")
-        .setDescription("Number of function invocations handled directly")
-        .setUnit("1")
-        .build()
-
-    /**
-     * The amount of function invocations that were delayed due to function deployment.
-     */
-    private val _delayedInvocations = meter.longCounterBuilder("service.invocations.cold")
-        .setDescription("Number of function invocations that are delayed")
-        .setUnit("1")
-        .build()
-
-    override fun newClient(): ServerlessClient {
-        return object : ServerlessClient {
-            private var isClosed: Boolean = false
-
-            /**
-             * Exposes a [FunctionObject] to a client-exposed [ServerlessFunction] instance.
-             */
-            private fun FunctionObject.asClientFunction(): ServerlessFunction {
-                return ServerlessFunctionImpl(this@ServerlessServiceImpl, this)
-            }
-
-            override suspend fun queryFunctions(): List<ServerlessFunction> {
-                check(!isClosed) { "Client is already closed" }
-
-                return functions.values.map { it.asClientFunction() }
-            }
-
-            override suspend fun findFunction(id: UUID): ServerlessFunction? {
-                check(!isClosed) { "Client is already closed" }
-
-                return functions[id]?.asClientFunction()
-            }
-
-            override suspend fun findFunction(name: String): ServerlessFunction? {
-                check(!isClosed) { "Client is already closed" }
-
-                return functionsByName[name]?.asClientFunction()
-            }
-
-            override suspend fun newFunction(
-                name: String,
-                memorySize: Long,
-                labels: Map<String, String>,
-                meta: Map<String, Any>
-            ): ServerlessFunction {
-                check(!isClosed) { "Client is already closed" }
-                require(name !in functionsByName) { "Function with same name exists" }
-
-                val uid = UUID(clock.millis(), random.nextLong())
-                val function = FunctionObject(
-                    meter,
-                    uid,
-                    name,
-                    memorySize,
-                    labels,
-                    meta
-                )
-
-                functionsByName[name] = function
-                functions[uid] = function
-
-                return function.asClientFunction()
-            }
-
-            override suspend fun invoke(name: String) {
-                check(!isClosed) { "Client is already closed" }
-
-                val func = requireNotNull(functionsByName[name]) { "Unknown function" }
-                this@ServerlessServiceImpl.invoke(func)
-            }
-
-            override fun close() {
-                isClosed = true
-            }
-        }
-    }
-
-    /**
-     * Indicate that a new scheduling cycle is needed due to a change to the service's state.
-     */
-    private fun schedule() {
-        // Bail out in case we have already requested a new cycle or the queue is empty.
-        if (scheduler.isTimerActive(Unit) || queue.isEmpty()) {
-            return
-        }
-
-        val quantum = 100
-
-        // We assume that the provisioner runs at a fixed slot every time quantum (e.g t=0, t=60, t=120).
-        // This is important because the slices of the VMs need to be aligned.
-        // We calculate here the delay until the next scheduling slot.
-        val delay = quantum - (clock.millis() % quantum)
-
-        scheduler.startSingleTimer(Unit, delay, ::doSchedule)
-    }
-
-    /**
-     * Run a single scheduling iteration.
-     */
-    @OptIn(InternalCoroutinesApi::class)
-    private fun doSchedule() {
-        try {
-            while (queue.isNotEmpty()) {
-                val (submitTime, function, cont) = queue.poll()
-
-                val instances = function.instances
-
-                // Check if there exists an instance of the function
-                val activeInstance = if (instances.isNotEmpty()) {
-                    routingPolicy.select(instances, function)
-                } else {
-                    null
-                }
-
-                val instance = if (activeInstance != null) {
-                    _timelyInvocations.add(1)
-                    function.timelyInvocations.add(1)
-
-                    activeInstance
-                } else {
-                    val instance = deployer.deploy(function)
-                    instances.add(instance)
-
-                    function.idleInstances.add(1)
-
-                    _delayedInvocations.add(1)
-                    function.delayedInvocations.add(1)
-
-                    instance
-                }
-
-                suspend {
-                    val start = clock.millis()
-                    function.waitTime.record(start - submitTime)
-                    function.idleInstances.add(-1)
-                    function.activeInstances.add(1)
-                    try {
-                        instance.invoke()
-                    } catch (e: Throwable) {
-                        logger.debug(e) { "Function invocation failed" }
-                        function.failedInvocations.add(1)
-                    } finally {
-                        val end = clock.millis()
-                        function.activeTime.record(end - start)
-                        function.idleInstances.add(1)
-                        function.activeInstances.add(-1)
-                    }
-                }.startCoroutineCancellable(cont)
-            }
-        } catch (cause: Throwable) {
-            logger.error(cause) { "Exception occurred during scheduling cycle" }
-        }
-    }
-
-    suspend fun invoke(function: FunctionObject) {
-        check(function.uid in functions) { "Function does not exist (anymore)" }
-
-        _invocations.add(1)
-        function.invocations.add(1)
-
-        return suspendCancellableCoroutine { cont ->
-            if (!queue.add(InvocationRequest(clock.millis(), function, cont))) {
-                cont.resumeWithException(IllegalStateException("Failed to enqueue request"))
-            } else {
-                schedule()
-            }
-        }
-    }
-
-    fun delete(function: FunctionObject) {
-        functions.remove(function.uid)
-        functionsByName.remove(function.name)
-    }
-
-    override fun close() {
-        scope.cancel()
-
-        // Stop all function instances
-        for ((_, function) in functions) {
-            function.close()
-        }
-    }
-
-    /**
-     * A request to invoke a function.
-     */
-    private data class InvocationRequest(val timestamp: Long, val function: FunctionObject, val cont: Continuation<Unit>)
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/router/RandomRoutingPolicy.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/router/RandomRoutingPolicy.kt
deleted file mode 100644
index 063fb80a..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/router/RandomRoutingPolicy.kt
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.router
-
-import org.opendc.serverless.service.FunctionObject
-import org.opendc.serverless.service.deployer.FunctionInstance
-import kotlin.random.Random
-
-/**
- * A [RoutingPolicy] that selects a random function instance.
- */
-public class RandomRoutingPolicy(private val random: Random = Random(0)) : RoutingPolicy {
-    override fun select(instances: List<FunctionInstance>, function: FunctionObject): FunctionInstance {
-        return instances.random(random)
-    }
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/router/RoutingPolicy.kt b/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/router/RoutingPolicy.kt
deleted file mode 100644
index d5d1166f..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/main/kotlin/org/opendc/serverless/service/router/RoutingPolicy.kt
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service.router
-
-import org.opendc.serverless.service.FunctionObject
-import org.opendc.serverless.service.deployer.FunctionInstance
-
-/**
- * A [RoutingPolicy] decides to which [FunctionInstance] a function invocation should be routed.
- */
-public interface RoutingPolicy {
-    /**
-     * Select the instance to which the request should be routed to.
-     */
-    public fun select(instances: List<FunctionInstance>, function: FunctionObject): FunctionInstance?
-}
diff --git a/simulator/opendc-serverless/opendc-serverless-service/src/test/kotlin/org/opendc/serverless/service/ServerlessServiceTest.kt b/simulator/opendc-serverless/opendc-serverless-service/src/test/kotlin/org/opendc/serverless/service/ServerlessServiceTest.kt
deleted file mode 100644
index d9f5ee81..00000000
--- a/simulator/opendc-serverless/opendc-serverless-service/src/test/kotlin/org/opendc/serverless/service/ServerlessServiceTest.kt
+++ /dev/null
@@ -1,186 +0,0 @@
-/*
- * Copyright (c) 2021 AtLarge Research
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-package org.opendc.serverless.service
-
-import io.mockk.*
-import io.opentelemetry.api.metrics.MeterProvider
-import kotlinx.coroutines.ExperimentalCoroutinesApi
-import org.junit.jupiter.api.Assertions.*
-import org.junit.jupiter.api.Test
-import org.junit.jupiter.api.assertDoesNotThrow
-import org.junit.jupiter.api.assertThrows
-import org.opendc.serverless.api.ServerlessFunction
-import org.opendc.serverless.service.deployer.FunctionDeployer
-import org.opendc.serverless.service.deployer.FunctionInstance
-import org.opendc.serverless.service.deployer.FunctionInstanceState
-import org.opendc.simulator.core.runBlockingSimulation
-import java.util.*
-
-/**
- * Test suite for the [ServerlessService] implementation.
- */
-@OptIn(ExperimentalCoroutinesApi::class)
-internal class ServerlessServiceTest {
-
-    @Test
-    fun testClientState() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = assertDoesNotThrow { service.newClient() }
-        assertDoesNotThrow { client.close() }
-
-        assertThrows<IllegalStateException> { client.queryFunctions() }
-        assertThrows<IllegalStateException> { client.newFunction("test", 128) }
-        assertThrows<IllegalStateException> { client.invoke("test") }
-        assertThrows<IllegalStateException> { client.findFunction(UUID.randomUUID()) }
-        assertThrows<IllegalStateException> { client.findFunction("name") }
-    }
-
-    @Test
-    fun testClientInvokeUnknown() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-
-        assertThrows<IllegalArgumentException> { client.invoke("test") }
-    }
-
-    @Test
-    fun testClientFunctionCreation() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-
-        val function = client.newFunction("test", 128)
-
-        assertEquals("test", function.name)
-    }
-
-    @Test
-    fun testClientFunctionQuery() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-
-        assertEquals(emptyList<ServerlessFunction>(), client.queryFunctions())
-
-        val function = client.newFunction("test", 128)
-
-        assertEquals(listOf(function), client.queryFunctions())
-    }
-
-    @Test
-    fun testClientFunctionFindById() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-
-        assertEquals(emptyList<ServerlessFunction>(), client.queryFunctions())
-
-        val function = client.newFunction("test", 128)
-
-        assertNotNull(client.findFunction(function.uid))
-    }
-
-    @Test
-    fun testClientFunctionFindByName() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-
-        assertEquals(emptyList<ServerlessFunction>(), client.queryFunctions())
-
-        val function = client.newFunction("test", 128)
-
-        assertNotNull(client.findFunction(function.name))
-    }
-
-    @Test
-    fun testClientFunctionDuplicateName() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-
-        client.newFunction("test", 128)
-
-        assertThrows<IllegalArgumentException> { client.newFunction("test", 128) }
-    }
-
-    @Test
-    fun testClientFunctionDelete() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-        val function = client.newFunction("test", 128)
-        assertNotNull(client.findFunction(function.uid))
-        function.delete()
-        assertNull(client.findFunction(function.uid))
-
-        // Delete should be idempotent
-        function.delete()
-    }
-
-    @Test
-    fun testClientFunctionCannotInvokeDeleted() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val service = ServerlessService(coroutineContext, clock, meter, mockk(), mockk())
-
-        val client = service.newClient()
-        val function = client.newFunction("test", 128)
-        assertNotNull(client.findFunction(function.uid))
-        function.delete()
-
-        assertThrows<IllegalStateException> { function.invoke() }
-    }
-
-    @Test
-    fun testClientFunctionInvoke() = runBlockingSimulation {
-        val meter = MeterProvider.noop().get("opendc-serverless")
-        val deployer = mockk<FunctionDeployer>()
-        val service = ServerlessService(coroutineContext, clock, meter, deployer, mockk())
-
-        every { deployer.deploy(any()) } answers {
-            object : FunctionInstance {
-                override val state: FunctionInstanceState = FunctionInstanceState.Idle
-                override val function: FunctionObject = it.invocation.args[0] as FunctionObject
-
-                override suspend fun invoke() {}
-
-                override fun close() {}
-            }
-        }
-
-        val client = service.newClient()
-        val function = client.newFunction("test", 128)
-
-        function.invoke()
-    }
-}