Custom detekt rule for logger usage check

Check if logger invocations don't use unoptimal invocations, eg.
concatenation `debug("a=" + a)` instead of lambda use `debug {"a=" + a}`

Unfortunately to avoid defining dependencies in many places and having
circural dependencies it was necessarry to reorganize the maven module
structure. The goal was to have `sources` module with production code and
`build` module with build-time tooling (detekt rules among them).

Issue-ID: DCAEGEN2-1002
Change-Id: I36e677b98972aaae6905d722597cbce5e863d201
Signed-off-by: Piotr Jaszczyk <piotr.jaszczyk@nokia.com>

14 files changed, 1249 insertions, 0 deletions

diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/DcaeAppSimulator.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/DcaeAppSimulator.kt
new file mode 100644
index 00000000..490cde4a
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/DcaeAppSimulator.kt
@@ -0,0 +1,74 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl
+
+import arrow.core.getOrElse
+import arrow.effects.IO
+import arrow.effects.fix
+import arrow.effects.instances.io.monadError.monadError
+import arrow.typeclasses.bindingCatch
+import org.onap.dcae.collectors.veshv.utils.arrow.getOption
+import org.onap.dcae.collectors.veshv.utils.logging.Logger
+import java.io.InputStream
+import java.util.concurrent.atomic.AtomicReference
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since August 2018
+ */
+class DcaeAppSimulator(private val consumerFactory: ConsumerFactory,
+                       private val messageStreamValidation: MessageStreamValidation) {
+    private val consumerState: AtomicReference<ConsumerStateProvider> = AtomicReference()
+
+    fun listenToTopics(topicsString: String) = listenToTopics(extractTopics(topicsString))
+
+    fun listenToTopics(topics: Set<String>): IO<Unit> = IO.monadError().bindingCatch {
+        if (topics.any { it.isBlank() })
+            throw IllegalArgumentException("Topic list cannot contain empty elements")
+        if (topics.isEmpty())
+            throw IllegalArgumentException("Topic list cannot be empty")
+
+        logger.info("Received new configuration. Creating consumer for topics: $topics")
+        consumerState.set(consumerFactory.createConsumerForTopics(topics).bind())
+    }.fix()
+
+    fun state() = consumerState.getOption().map { it.currentState() }
+
+    fun resetState(): IO<Unit> = consumerState.getOption().fold(
+            { IO.unit },
+            { it.reset() }
+    )
+
+    fun validate(jsonDescription: InputStream) = messageStreamValidation.validate(jsonDescription, currentMessages())
+
+    private fun currentMessages(): List<ByteArray> =
+            consumerState.getOption()
+                    .map { it.currentState().consumedMessages }
+                    .getOrElse(::emptyList)
+
+    private fun extractTopics(topicsString: String): Set<String> =
+            topicsString.substringAfter("=")
+                    .split(",")
+                    .toSet()
+
+    companion object {
+        private val logger = Logger(DcaeAppSimulator::class)
+    }
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt
new file mode 100644
index 00000000..e423191d
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt
@@ -0,0 +1,88 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl
+
+import arrow.effects.IO
+import arrow.effects.fix
+import arrow.effects.instances.io.monadError.monadError
+import arrow.typeclasses.bindingCatch
+import org.onap.dcae.collectors.veshv.domain.ByteData
+import org.onap.dcae.collectors.veshv.domain.WireFrameMessage
+import org.onap.dcae.collectors.veshv.utils.arrow.asIo
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageGenerator
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageParameters
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageParametersParser
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageType
+import org.onap.ves.VesEventOuterClass
+import java.io.InputStream
+import javax.json.Json
+
+class MessageStreamValidation(
+        private val messageGenerator: MessageGenerator,
+        private val messageParametersParser: MessageParametersParser = MessageParametersParser.INSTANCE) {
+
+    fun validate(jsonDescription: InputStream, consumedMessages: List<ByteArray>): IO<Boolean> =
+            IO.monadError().bindingCatch {
+                val messageParams = parseMessageParams(jsonDescription)
+                val expectedEvents = generateEvents(messageParams).bind()
+                val actualEvents = decodeConsumedEvents(consumedMessages)
+                if (shouldValidatePayloads(messageParams)) {
+                    expectedEvents == actualEvents
+                } else {
+                    validateHeaders(actualEvents, expectedEvents)
+                }
+            }.fix()
+
+    private fun parseMessageParams(input: InputStream): List<MessageParameters> {
+        val expectations = Json.createReader(input).readArray()
+        val messageParams = messageParametersParser.parse(expectations)
+
+        return messageParams.fold(
+                { throw IllegalArgumentException("Parsing error: " + it.message) },
+                {
+                    if (it.isEmpty())
+                        throw IllegalArgumentException("Message param list cannot be empty")
+                    it
+                }
+        )
+    }
+
+    private fun shouldValidatePayloads(parameters: List<MessageParameters>) =
+            parameters.all { it.messageType == MessageType.FIXED_PAYLOAD }
+
+    private fun validateHeaders(actual: List<VesEventOuterClass.VesEvent>,
+                                expected: List<VesEventOuterClass.VesEvent>): Boolean {
+        val consumedHeaders = actual.map { it.commonEventHeader }
+        val generatedHeaders = expected.map { it.commonEventHeader }
+        return generatedHeaders == consumedHeaders
+    }
+
+    private fun generateEvents(parameters: List<MessageParameters>): IO<List<VesEventOuterClass.VesEvent>> =
+            messageGenerator.createMessageFlux(parameters)
+                    .map(WireFrameMessage::payload)
+                    .map(ByteData::unsafeAsArray)
+                    .map(VesEventOuterClass.VesEvent::parseFrom)
+                    .collectList()
+                    .asIo()
+
+    private fun decodeConsumedEvents(consumedMessages: List<ByteArray>) =
+            consumedMessages.map(VesEventOuterClass.VesEvent::parseFrom)
+
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/DcaeAppApiServer.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/DcaeAppApiServer.kt
new file mode 100644
index 00000000..1eca9317
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/DcaeAppApiServer.kt
@@ -0,0 +1,101 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.adapters
+
+import arrow.effects.IO
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.DcaeAppSimulator
+import org.onap.dcae.collectors.veshv.utils.http.HttpConstants
+import org.onap.dcae.collectors.veshv.utils.http.HttpStatus
+import org.onap.dcae.collectors.veshv.utils.http.Responses
+import org.onap.dcae.collectors.veshv.utils.http.sendAndHandleErrors
+import org.onap.dcae.collectors.veshv.utils.http.sendOrError
+import ratpack.handling.Chain
+import ratpack.server.RatpackServer
+import ratpack.server.ServerConfig
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since May 2018
+ */
+class DcaeAppApiServer(private val simulator: DcaeAppSimulator) {
+    private val responseValid by lazy {
+        Responses.statusResponse(
+                name = "valid",
+                message = "validation succeeded"
+        )
+    }
+
+    private val responseInvalid by lazy {
+        Responses.statusResponse(
+                name = "invalid",
+                message = "validation failed",
+                httpStatus = HttpStatus.BAD_REQUEST
+        )
+    }
+
+
+    fun start(port: Int, kafkaTopics: Set<String>): IO<RatpackServer> =
+            simulator.listenToTopics(kafkaTopics).map {
+                RatpackServer.start { server ->
+                    server.serverConfig(ServerConfig.embedded().port(port))
+                            .handlers(::setupHandlers)
+                }
+            }
+
+    private fun setupHandlers(chain: Chain) {
+        chain
+                .put("configuration/topics") { ctx ->
+                    ctx.request.body.then { body ->
+                        val operation = simulator.listenToTopics(body.text)
+                        ctx.response.sendOrError(operation)
+                    }
+
+                }
+                .delete("messages") { ctx ->
+                    ctx.response.contentType(CONTENT_TEXT)
+                    ctx.response.sendOrError(simulator.resetState())
+                }
+                .get("messages/all/count") { ctx ->
+                    simulator.state().fold(
+                            { ctx.response.status(HttpConstants.STATUS_NOT_FOUND) },
+                            {
+                                ctx.response
+                                        .contentType(CONTENT_TEXT)
+                                        .send(it.messagesCount.toString())
+                            })
+                }
+                .post("messages/all/validate") { ctx ->
+                    ctx.request.body.then { body ->
+                        val response = simulator.validate(body.inputStream)
+                                .map { isValid ->
+                                    if (isValid) responseValid else responseInvalid
+                                }
+                        ctx.response.sendAndHandleErrors(response)
+                    }
+                }
+                .get("healthcheck") { ctx ->
+                    ctx.response.status(HttpConstants.STATUS_OK).send()
+                }
+    }
+
+    companion object {
+        private const val CONTENT_TEXT = "text/plain"
+    }
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/KafkaSource.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/KafkaSource.kt
new file mode 100644
index 00000000..10dedbdf
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/KafkaSource.kt
@@ -0,0 +1,66 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.adapters
+
+import arrow.effects.IO
+import org.apache.kafka.clients.consumer.ConsumerConfig
+import org.apache.kafka.common.serialization.ByteArrayDeserializer
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.Consumer
+import org.onap.dcae.collectors.veshv.utils.arrow.evaluateIo
+import org.onap.dcae.collectors.veshv.utils.logging.Logger
+import reactor.kafka.receiver.KafkaReceiver
+import reactor.kafka.receiver.ReceiverOptions
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since May 2018
+ */
+class KafkaSource(private val receiver: KafkaReceiver<ByteArray, ByteArray>) {
+
+    fun start(): IO<Consumer> = IO {
+        val consumer = Consumer()
+        receiver.receive().map(consumer::update).evaluateIo().subscribe()
+        consumer
+    }
+
+    companion object {
+        private val logger = Logger(KafkaSource::class)
+
+        fun create(bootstrapServers: String, topics: Set<String>): KafkaSource {
+            return KafkaSource(KafkaReceiver.create(createReceiverOptions(bootstrapServers, topics)))
+        }
+
+        fun createReceiverOptions(bootstrapServers: String,
+                                  topics: Set<String>): ReceiverOptions<ByteArray, ByteArray>? {
+            val props = mapOf<String, Any>(
+                    ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG to bootstrapServers,
+                    ConsumerConfig.CLIENT_ID_CONFIG to "hv-collector-dcae-app-simulator",
+                    ConsumerConfig.GROUP_ID_CONFIG to "hv-collector-simulators",
+                    ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG to ByteArrayDeserializer::class.java,
+                    ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG to ByteArrayDeserializer::class.java,
+                    ConsumerConfig.AUTO_OFFSET_RESET_CONFIG to "earliest"
+            )
+            return ReceiverOptions.create<ByteArray, ByteArray>(props)
+                    .addAssignListener { partitions -> logger.debug { "Partitions assigned $partitions" } }
+                    .addRevokeListener { partitions -> logger.debug { "Partitions revoked $partitions" } }
+                    .subscription(topics)
+        }
+    }
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/ArgDcaeAppSimConfiguration.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/ArgDcaeAppSimConfiguration.kt
new file mode 100644
index 00000000..17eeb5b1
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/ArgDcaeAppSimConfiguration.kt
@@ -0,0 +1,67 @@
+/*
+* ============LICENSE_START=======================================================
+* dcaegen2-collectors-veshv
+* ================================================================================
+* Copyright (C) 2018 NOKIA
+* ================================================================================
+* 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.
+* ============LICENSE_END=========================================================
+*/
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.config
+
+import arrow.core.Option
+import arrow.core.fix
+import arrow.instances.option.monad.monad
+import arrow.typeclasses.binding
+import org.apache.commons.cli.CommandLine
+import org.apache.commons.cli.DefaultParser
+import org.onap.dcae.collectors.veshv.domain.WireFrameMessage
+import org.onap.dcae.collectors.veshv.utils.commandline.ArgBasedConfiguration
+import org.onap.dcae.collectors.veshv.utils.commandline.CommandLineOption
+import org.onap.dcae.collectors.veshv.utils.commandline.CommandLineOption.KAFKA_SERVERS
+import org.onap.dcae.collectors.veshv.utils.commandline.CommandLineOption.KAFKA_TOPICS
+import org.onap.dcae.collectors.veshv.utils.commandline.CommandLineOption.LISTEN_PORT
+import org.onap.dcae.collectors.veshv.utils.commandline.CommandLineOption.MAXIMUM_PAYLOAD_SIZE_BYTES
+import org.onap.dcae.collectors.veshv.utils.commandline.intValue
+import org.onap.dcae.collectors.veshv.utils.commandline.stringValue
+
+class ArgDcaeAppSimConfiguration : ArgBasedConfiguration<DcaeAppSimConfiguration>(DefaultParser()) {
+    override val cmdLineOptionsList: List<CommandLineOption> = listOf(
+            LISTEN_PORT,
+            MAXIMUM_PAYLOAD_SIZE_BYTES,
+            KAFKA_SERVERS,
+            KAFKA_TOPICS
+    )
+
+    override fun getConfiguration(cmdLine: CommandLine): Option<DcaeAppSimConfiguration> =
+            Option.monad().binding {
+                val listenPort = cmdLine
+                        .intValue(LISTEN_PORT)
+                        .bind()
+                val maxPayloadSizeBytes = cmdLine
+                        .intValue(MAXIMUM_PAYLOAD_SIZE_BYTES, WireFrameMessage.DEFAULT_MAX_PAYLOAD_SIZE_BYTES)
+                val kafkaBootstrapServers = cmdLine
+                        .stringValue(KAFKA_SERVERS)
+                        .bind()
+                val kafkaTopics = cmdLine
+                        .stringValue(KAFKA_TOPICS)
+                        .map { it.split(",").toSet() }
+                        .bind()
+
+                DcaeAppSimConfiguration(
+                        listenPort,
+                        maxPayloadSizeBytes,
+                        kafkaBootstrapServers,
+                        kafkaTopics)
+            }.fix()
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/DcaeAppSimConfiguration.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/DcaeAppSimConfiguration.kt
new file mode 100644
index 00000000..a6fc8053
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/DcaeAppSimConfiguration.kt
@@ -0,0 +1,27 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.config
+
+data class DcaeAppSimConfiguration(
+        val apiPort: Int,
+        val maxPayloadSizeBytes: Int,
+        val kafkaBootstrapServers: String,
+        val kafkaTopics: Set<String>
+)
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/consumer.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/consumer.kt
new file mode 100644
index 00000000..1eefdbdb
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/consumer.kt
@@ -0,0 +1,70 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl
+
+import arrow.effects.IO
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.adapters.KafkaSource
+import org.onap.dcae.collectors.veshv.utils.logging.Logger
+import reactor.kafka.receiver.ReceiverRecord
+import java.util.concurrent.ConcurrentLinkedQueue
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since June 2018
+ */
+class ConsumerState(private val messages: ConcurrentLinkedQueue<ByteArray>) {
+    val messagesCount: Int by lazy {
+        messages.size
+    }
+
+    val consumedMessages: List<ByteArray> by lazy {
+        messages.toList()
+    }
+}
+
+interface ConsumerStateProvider {
+    fun currentState(): ConsumerState
+    fun reset(): IO<Unit>
+}
+
+class Consumer : ConsumerStateProvider {
+
+    private var consumedMessages: ConcurrentLinkedQueue<ByteArray> = ConcurrentLinkedQueue()
+
+    override fun currentState(): ConsumerState = ConsumerState(consumedMessages)
+
+    override fun reset(): IO<Unit> = IO {
+        consumedMessages.clear()
+    }
+
+    fun update(record: ReceiverRecord<ByteArray, ByteArray>) = IO<Unit> {
+        logger.trace { "Updating stats for message from ${record.topic()}:${record.partition()}" }
+        consumedMessages.add(record.value())
+    }
+
+    companion object {
+        private val logger = Logger(Consumer::class)
+    }
+}
+
+class ConsumerFactory(private val kafkaBootstrapServers: String) {
+    fun createConsumerForTopics(kafkaTopics: Set<String>): IO<Consumer> =
+            KafkaSource.create(kafkaBootstrapServers, kafkaTopics.toSet()).start()
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt
new file mode 100644
index 00000000..06ff4d59
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt
@@ -0,0 +1,62 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp
+
+import arrow.effects.IO
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.config.ArgDcaeAppSimConfiguration
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.config.DcaeAppSimConfiguration
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.ConsumerFactory
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.DcaeAppSimulator
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.MessageStreamValidation
+import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.adapters.DcaeAppApiServer
+import org.onap.dcae.collectors.veshv.utils.arrow.ExitFailure
+import org.onap.dcae.collectors.veshv.utils.arrow.unsafeRunEitherSync
+import org.onap.dcae.collectors.veshv.utils.arrow.unit
+import org.onap.dcae.collectors.veshv.utils.commandline.handleWrongArgumentErrorCurried
+import org.onap.dcae.collectors.veshv.utils.logging.Logger
+import org.onap.dcae.collectors.veshv.ves.message.generator.factory.MessageGeneratorFactory
+
+private const val PACKAGE_NAME = "org.onap.dcae.collectors.veshv.simulators.dcaeapp"
+private val logger = Logger(PACKAGE_NAME)
+const val PROGRAM_NAME = "java $PACKAGE_NAME.MainKt"
+
+fun main(args: Array<String>) =
+        ArgDcaeAppSimConfiguration().parse(args)
+                .mapLeft(handleWrongArgumentErrorCurried(PROGRAM_NAME))
+                .map(::startApp)
+                .unsafeRunEitherSync(
+                        { ex ->
+                            logger.error("Failed to start a server", ex)
+                            ExitFailure(1)
+                        },
+                        {
+                            logger.info("Started DCAE-APP Simulator API server")
+                        }
+                )
+
+
+private fun startApp(config: DcaeAppSimConfiguration): IO<Unit> {
+    logger.info("Using configuration: $config")
+    val consumerFactory = ConsumerFactory(config.kafkaBootstrapServers)
+    val messageStreamValidation = MessageStreamValidation(MessageGeneratorFactory.create(config.maxPayloadSizeBytes))
+    return DcaeAppApiServer(DcaeAppSimulator(consumerFactory, messageStreamValidation))
+            .start(config.apiPort, config.kafkaTopics)
+            .unit()
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/main/resources/logback.xml b/sources/hv-collector-dcae-app-simulator/src/main/resources/logback.xml
new file mode 100644
index 00000000..48da3b18
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/main/resources/logback.xml
@@ -0,0 +1,36 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+  <property name="LOG_FILE"
+    value="${LOG_FILE:-${LOG_PATH:-${LOG_TEMP:-${java.io.tmpdir:-/tmp}}/}ves-hv.log}"/>
+  <property name="FILE_LOG_PATTERN" value="%d{yyyy-MM-dd'T'HH:mm:ss.SSSXXX,UTC} %-5level [%-40.40logger{10}] - %msg%n"/>
+
+  <appender name="CONSOLE" class="ch.qos.logback.core.ConsoleAppender">
+    <encoder>
+      <pattern>
+        %d{yyyy-MM-dd'T'HH:mm:ss.SSSXXX,UTC} %highlight(%-5level) [%-40.40logger{10}] - %msg%n
+      </pattern>
+    </encoder>
+  </appender>
+
+    <appender name="ROLLING-FILE"
+      class="ch.qos.logback.core.rolling.RollingFileAppender">
+      <encoder>
+        <pattern>${FILE_LOG_PATTERN}</pattern>
+      </encoder>
+      <file>${LOG_FILE}</file>
+      <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
+        <fileNamePattern>${LOG_FILE}.%d{yyyy-MM-dd}.log</fileNamePattern>
+        <maxFileSize>50MB</maxFileSize>
+        <maxHistory>30</maxHistory>
+        <totalSizeCap>10GB</totalSizeCap>
+      </rollingPolicy>
+    </appender>
+
+  <logger name="org.onap.dcae.collectors.veshv" level="INFO"/>
+  <!--<logger name="reactor.ipc.netty" level="DEBUG"/>-->
+
+  <root level="INFO">
+      <appender-ref ref="CONSOLE"/>
+      <appender-ref ref="ROLLING-FILE"/>
+    </root>
+</configuration>
\ No newline at end of file
diff --git a/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/ConsumerTest.kt b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/ConsumerTest.kt
new file mode 100644
index 00000000..08558d76
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/ConsumerTest.kt
@@ -0,0 +1,82 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl
+
+import org.apache.kafka.clients.consumer.ConsumerRecord
+import org.assertj.core.api.Assertions.assertThat
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+import reactor.kafka.receiver.ReceiverRecord
+
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since August 2018
+ */
+internal class ConsumerTest : Spek({
+
+    lateinit var cut: Consumer
+
+    beforeEachTest {
+        cut = Consumer()
+    }
+
+    describe("Consumer which holds the state of received Kafka records") {
+        it("should contain empty state in the beginning") {
+            assertEmptyState(cut)
+        }
+
+        describe("update") {
+            val value = byteArrayOf(2)
+
+            beforeEachTest {
+                cut.update(receiverRecord(
+                        topic = "topic",
+                        key = byteArrayOf(1),
+                        value = value
+                )).unsafeRunSync()
+            }
+
+            it("should contain one message if it was updated once") {
+                assertState(cut, value)
+            }
+
+            it("should contain empty state message if it was reset after update") {
+                cut.reset().unsafeRunSync()
+                assertEmptyState(cut)
+            }
+        }
+    }
+})
+
+fun assertEmptyState(cut: Consumer) {
+    assertState(cut)
+}
+
+fun assertState(cut: Consumer, vararg values: ByteArray) {
+    assertThat(cut.currentState().consumedMessages)
+            .containsOnly(*values)
+    assertThat(cut.currentState().messagesCount)
+            .isEqualTo(values.size)
+}
+
+fun receiverRecord(topic: String, key: ByteArray, value: ByteArray) =
+        ReceiverRecord(ConsumerRecord(topic, 1, 100L, key, value), null)
diff --git a/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/DcaeAppSimulatorTest.kt b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/DcaeAppSimulatorTest.kt
new file mode 100644
index 00000000..e1641cbb
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/DcaeAppSimulatorTest.kt
@@ -0,0 +1,183 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl
+
+import arrow.core.Left
+import arrow.core.None
+import arrow.core.Some
+import arrow.effects.IO
+import com.google.protobuf.ByteString
+import com.nhaarman.mockitokotlin2.any
+import com.nhaarman.mockitokotlin2.eq
+import com.nhaarman.mockitokotlin2.mock
+import com.nhaarman.mockitokotlin2.never
+import com.nhaarman.mockitokotlin2.verify
+import com.nhaarman.mockitokotlin2.whenever
+import org.assertj.core.api.Assertions.assertThat
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+import org.mockito.ArgumentMatchers.anySet
+import org.onap.ves.VesEventOuterClass.CommonEventHeader
+import org.onap.ves.VesEventOuterClass.VesEvent
+import java.util.concurrent.ConcurrentLinkedQueue
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since August 2018
+ */
+internal class DcaeAppSimulatorTest : Spek({
+    lateinit var consumerFactory: ConsumerFactory
+    lateinit var messageStreamValidation: MessageStreamValidation
+    lateinit var consumer: Consumer
+    lateinit var cut: DcaeAppSimulator
+
+    beforeEachTest {
+        consumerFactory = mock()
+        messageStreamValidation = mock()
+        consumer = mock()
+        cut = DcaeAppSimulator(consumerFactory, messageStreamValidation)
+
+        whenever(consumerFactory.createConsumerForTopics(anySet())).thenReturn(IO.just(consumer))
+    }
+
+    fun consumerState(vararg messages: ByteArray) = ConsumerState(ConcurrentLinkedQueue(messages.toList()))
+
+    describe("listenToTopics") {
+        val topics = setOf("perf3gpp", "faults")
+
+        it("should fail when topic list is empty") {
+            val result = cut.listenToTopics(setOf()).attempt().unsafeRunSync()
+            assertThat(result.isLeft()).isTrue()
+        }
+
+        it("should fail when topic list contains empty strings") {
+            val result = cut.listenToTopics(setOf("perf3gpp", " ", "faults")).attempt().unsafeRunSync()
+            assertThat(result.isLeft()).isTrue()
+        }
+
+        it("should subscribe to given topics") {
+            cut.listenToTopics(topics).unsafeRunSync()
+            verify(consumerFactory).createConsumerForTopics(topics)
+        }
+
+        it("should subscribe to given topics when called with comma separated list") {
+            cut.listenToTopics("perf3gpp,faults").unsafeRunSync()
+            verify(consumerFactory).createConsumerForTopics(topics)
+        }
+
+        it("should handle errors") {
+            // given
+            val error = RuntimeException("WTF")
+            whenever(consumerFactory.createConsumerForTopics(anySet()))
+                    .thenReturn(IO.raiseError(error))
+
+            // when
+            val result = cut.listenToTopics("perf3gpp").attempt().unsafeRunSync()
+
+            // then
+            assertThat(result).isEqualTo(Left(error))
+        }
+    }
+
+    describe("state") {
+
+        it("should return None when topics hasn't been initialized") {
+            assertThat(cut.state()).isEqualTo(None)
+        }
+
+        describe("when topics are initialized") {
+            beforeEachTest {
+                cut.listenToTopics("perf3gpp").unsafeRunSync()
+            }
+
+            it("should return some state when it has been set") {
+                val state = consumerState()
+                whenever(consumer.currentState()).thenReturn(state)
+
+                assertThat(cut.state()).isEqualTo(Some(state))
+            }
+        }
+    }
+
+    describe("resetState") {
+        it("should do nothing when topics hasn't been initialized") {
+            cut.resetState().unsafeRunSync()
+            verify(consumer, never()).reset()
+        }
+
+        describe("when topics are initialized") {
+            beforeEachTest {
+                cut.listenToTopics("perf3gpp").unsafeRunSync()
+            }
+
+            it("should reset the state") {
+                // given
+                whenever(consumer.reset()).thenReturn(IO.unit)
+
+                // when
+                cut.resetState().unsafeRunSync()
+
+                // then
+                verify(consumer).reset()
+            }
+        }
+    }
+
+    describe("validate") {
+        beforeEachTest {
+            whenever(messageStreamValidation.validate(any(), any())).thenReturn(IO.just(true))
+        }
+
+        it("should use empty list when consumer is unavailable") {
+            // when
+            val result = cut.validate("['The JSON']".byteInputStream()).unsafeRunSync()
+
+            // then
+            verify(messageStreamValidation).validate(any(), eq(emptyList()))
+            assertThat(result).isTrue()
+        }
+
+        it("should delegate to MessageStreamValidation") {
+            // given
+            cut.listenToTopics("perf3gpp").unsafeRunSync()
+            whenever(consumer.currentState()).thenReturn(consumerState(vesEvent().toByteArray()))
+
+            // when
+            val result = cut.validate("['The JSON']".byteInputStream()).unsafeRunSync()
+
+            // then
+            verify(messageStreamValidation).validate(any(), any())
+            assertThat(result).isTrue()
+        }
+    }
+})
+
+
+private const val DUMMY_EVENT_ID = "aaa"
+private const val DUMMY_PAYLOAD = "payload"
+
+private fun vesEvent(eventId: String = DUMMY_EVENT_ID, payload: String = DUMMY_PAYLOAD): VesEvent {
+    return VesEvent.newBuilder()
+            .setCommonEventHeader(CommonEventHeader.newBuilder()
+                    .setEventId(eventId))
+            .setEventFields(ByteString.copyFrom(payload.toByteArray()))
+            .build()
+}
diff --git a/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidationTest.kt b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidationTest.kt
new file mode 100644
index 00000000..a631be76
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidationTest.kt
@@ -0,0 +1,214 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl
+
+import arrow.core.Either
+import arrow.core.Right
+import com.google.protobuf.ByteString
+import com.nhaarman.mockitokotlin2.any
+import com.nhaarman.mockitokotlin2.mock
+import com.nhaarman.mockitokotlin2.whenever
+import org.assertj.core.api.Assertions.assertThat
+import org.assertj.core.api.Assertions.fail
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+import org.mockito.ArgumentMatchers.anyList
+import org.onap.dcae.collectors.veshv.domain.WireFrameMessage
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageGenerator
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageParameters
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageParametersParser
+import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageType
+import org.onap.ves.VesEventOuterClass.CommonEventHeader
+import org.onap.ves.VesEventOuterClass.VesEvent
+import reactor.core.publisher.Flux
+import javax.json.stream.JsonParsingException
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
+ * @since August 2018
+ */
+internal class MessageStreamValidationTest : Spek({
+    lateinit var messageParametersParser: MessageParametersParser
+    lateinit var messageGenerator: MessageGenerator
+    lateinit var cut: MessageStreamValidation
+
+    beforeEachTest {
+        messageParametersParser = mock()
+        messageGenerator = mock()
+        cut = MessageStreamValidation(messageGenerator, messageParametersParser)
+    }
+
+    fun givenParsedMessageParameters(vararg params: MessageParameters) {
+        whenever(messageParametersParser.parse(any())).thenReturn(Right(params.toList()))
+    }
+
+    describe("validate") {
+
+        it("should return error when JSON is invalid") {
+            // when
+            val result = cut.validate("[{invalid json}]".byteInputStream(), listOf()).attempt().unsafeRunSync()
+
+            // then
+            when(result) {
+                is Either.Left -> assertThat(result.a).isInstanceOf(JsonParsingException::class.java)
+                else -> fail("validation should fail")
+            }
+        }
+
+        it("should return error when message param list is empty") {
+            // given
+            givenParsedMessageParameters()
+
+            // when
+            val result = cut.validate(sampleJsonAsStream(), listOf()).attempt().unsafeRunSync()
+
+            // then
+            assertThat(result.isLeft()).isTrue()
+        }
+
+        describe("when validating headers only") {
+            it("should return true when messages are the same") {
+                // given
+                val jsonAsStream = sampleJsonAsStream()
+                val event = vesEvent()
+                val generatedWireProtocolFrame = WireFrameMessage(event.toByteArray())
+                val receivedMessageBytes = event.toByteArray()
+
+                givenParsedMessageParameters(MessageParameters(event.commonEventHeader, MessageType.VALID, 1))
+                whenever(messageGenerator.createMessageFlux(anyList())).thenReturn(Flux.just(generatedWireProtocolFrame))
+
+                // when
+                val result = cut.validate(jsonAsStream, listOf(receivedMessageBytes)).unsafeRunSync()
+
+                // then
+                assertThat(result).isTrue()
+            }
+
+            it("should return true when messages differ with payload only") {
+                // given
+                val jsonAsStream = sampleJsonAsStream()
+                val generatedEvent = vesEvent(payload = "payload A")
+                val receivedEvent = vesEvent(payload = "payload B")
+                val generatedWireProtocolFrame = WireFrameMessage(generatedEvent.toByteArray())
+                val receivedMessageBytes = receivedEvent.toByteArray()
+
+                givenParsedMessageParameters(MessageParameters(generatedEvent.commonEventHeader, MessageType.VALID, 1))
+                whenever(messageGenerator.createMessageFlux(anyList())).thenReturn(Flux.just(generatedWireProtocolFrame))
+
+                // when
+                val result = cut.validate(jsonAsStream, listOf(receivedMessageBytes)).unsafeRunSync()
+
+                // then
+                assertThat(result).isTrue()
+            }
+
+            it("should return false when messages are different") {
+                // given
+                val jsonAsStream = sampleJsonAsStream()
+                val generatedEvent = vesEvent()
+                val receivedEvent = vesEvent(eventId = "bbb")
+                val generatedWireProtocolFrame = WireFrameMessage(generatedEvent.toByteArray())
+                val receivedMessageBytes = receivedEvent.toByteArray()
+
+                givenParsedMessageParameters(MessageParameters(generatedEvent.commonEventHeader, MessageType.VALID, 1))
+                whenever(messageGenerator.createMessageFlux(anyList())).thenReturn(Flux.just(generatedWireProtocolFrame))
+
+                // when
+                val result = cut.validate(jsonAsStream, listOf(receivedMessageBytes)).unsafeRunSync()
+
+                // then
+                assertThat(result).isFalse()
+            }
+        }
+
+        describe("when validating whole messages") {
+            it("should return true when messages are the same") {
+                // given
+                val jsonAsStream = sampleJsonAsStream()
+                val event = vesEvent()
+                val generatedWireProtocolFrame = WireFrameMessage(event.toByteArray())
+                val receivedMessageBytes = event.toByteArray()
+
+                givenParsedMessageParameters(MessageParameters(event.commonEventHeader, MessageType.FIXED_PAYLOAD, 1))
+                whenever(messageGenerator.createMessageFlux(anyList())).thenReturn(Flux.just(generatedWireProtocolFrame))
+
+                // when
+                val result = cut.validate(jsonAsStream, listOf(receivedMessageBytes)).unsafeRunSync()
+
+                // then
+                assertThat(result).isTrue()
+            }
+
+            it("should return false when messages differ with payload only") {
+                // given
+                val jsonAsStream = sampleJsonAsStream()
+                val generatedEvent = vesEvent(payload = "payload A")
+                val receivedEvent = vesEvent(payload = "payload B")
+                val generatedWireProtocolFrame = WireFrameMessage(generatedEvent.toByteArray())
+                val receivedMessageBytes = receivedEvent.toByteArray()
+
+                givenParsedMessageParameters(MessageParameters(generatedEvent.commonEventHeader, MessageType.FIXED_PAYLOAD, 1))
+                whenever(messageGenerator.createMessageFlux(anyList())).thenReturn(Flux.just(generatedWireProtocolFrame))
+
+                // when
+                val result = cut.validate(jsonAsStream, listOf(receivedMessageBytes)).unsafeRunSync()
+
+                // then
+                assertThat(result).isFalse()
+            }
+
+            it("should return false when messages are different") {
+                // given
+                val jsonAsStream = sampleJsonAsStream()
+                val generatedEvent = vesEvent()
+                val receivedEvent = vesEvent("bbb")
+                val generatedWireProtocolFrame = WireFrameMessage(generatedEvent.toByteArray())
+                val receivedMessageBytes = receivedEvent.toByteArray()
+
+                givenParsedMessageParameters(MessageParameters(generatedEvent.commonEventHeader, MessageType.FIXED_PAYLOAD, 1))
+                whenever(messageGenerator.createMessageFlux(anyList())).thenReturn(Flux.just(generatedWireProtocolFrame))
+
+                // when
+                val result = cut.validate(jsonAsStream, listOf(receivedMessageBytes)).unsafeRunSync()
+
+                // then
+                assertThat(result).isFalse()
+            }
+        }
+    }
+})
+
+
+
+private const val DUMMY_EVENT_ID = "aaa"
+private const val DUMMY_PAYLOAD = "payload"
+
+private fun vesEvent(eventId: String = DUMMY_EVENT_ID, payload: String = DUMMY_PAYLOAD): VesEvent {
+    return VesEvent.newBuilder()
+            .setCommonEventHeader(CommonEventHeader.newBuilder()
+                    .setEventId(eventId))
+            .setEventFields(ByteString.copyFrom(payload.toByteArray()))
+            .build()
+}
+
+private const val sampleJsonArray = """["headersOnly"]"""
+
+private fun sampleJsonAsStream() = sampleJsonArray.byteInputStream()
diff --git a/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/KafkaSourceTest.kt b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/KafkaSourceTest.kt
new file mode 100644
index 00000000..de74f628
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/KafkaSourceTest.kt
@@ -0,0 +1,54 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.adapters
+
+import org.apache.kafka.clients.consumer.ConsumerConfig
+import org.apache.kafka.common.serialization.ByteArrayDeserializer
+import org.assertj.core.api.Assertions.assertThat
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.it
+
+/**
+ * @author Piotr Jaszczyk <piotr.jaszczyk></piotr.jaszczyk>@nokia.com>
+ * @since August 2018
+ */
+internal class KafkaSourceTest : Spek({
+    val servers = "kafka1:9080,kafka2:9080"
+    val topics = setOf("topic1", "topic2")
+
+    describe("receiver options") {
+        val options = KafkaSource.createReceiverOptions(servers, topics)!!.toImmutable()
+
+        fun verifyProperty(key: String, expectedValue: Any) {
+            it("should have $key option set") {
+                assertThat(options.consumerProperty(key))
+                        .isEqualTo(expectedValue)
+            }
+        }
+
+        verifyProperty(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, servers)
+        verifyProperty(ConsumerConfig.CLIENT_ID_CONFIG, "hv-collector-dcae-app-simulator")
+        verifyProperty(ConsumerConfig.GROUP_ID_CONFIG, "hv-collector-simulators")
+        verifyProperty(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, ByteArrayDeserializer::class.java)
+        verifyProperty(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, ByteArrayDeserializer::class.java)
+        verifyProperty(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest")
+    }
+})
\ No newline at end of file
diff --git a/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/ArgDcaeAppSimConfigurationTest.kt b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/ArgDcaeAppSimConfigurationTest.kt
new file mode 100644
index 00000000..7137fe12
--- /dev/null
+++ b/sources/hv-collector-dcae-app-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/config/ArgDcaeAppSimConfigurationTest.kt
@@ -0,0 +1,125 @@
+/*
+ * ============LICENSE_START=======================================================
+ * dcaegen2-collectors-veshv
+ * ================================================================================
+ * Copyright (C) 2018 NOKIA
+ * ================================================================================
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.config
+
+import org.assertj.core.api.Assertions.assertThat
+import org.jetbrains.spek.api.Spek
+import org.jetbrains.spek.api.dsl.describe
+import org.jetbrains.spek.api.dsl.given
+import org.jetbrains.spek.api.dsl.it
+import org.onap.dcae.collectors.veshv.tests.utils.parseExpectingFailure
+import org.onap.dcae.collectors.veshv.tests.utils.parseExpectingSuccess
+import org.onap.dcae.collectors.veshv.utils.commandline.WrongArgumentError
+
+
+internal class ArgDcaeAppSimConfigurationTest : Spek({
+
+    lateinit var cut: ArgDcaeAppSimConfiguration
+    val listenPort = "1234"
+    val kafkaBootstrapServers = "localhosting:123,localhostinger:12345"
+    val kafkaTopics = "top1,top2"
+
+    beforeEachTest {
+        cut = ArgDcaeAppSimConfiguration()
+    }
+
+    describe("parsing arguments") {
+        lateinit var result: DcaeAppSimConfiguration
+
+        given("all parameters are present in the long form") {
+
+            beforeEachTest {
+                result = cut.parseExpectingSuccess(
+                        "--listen-port", listenPort,
+                        "--kafka-bootstrap-servers", kafkaBootstrapServers,
+                        "--kafka-topics", kafkaTopics
+                )
+            }
+
+            it("should set proper port") {
+                assertThat(result.apiPort).isEqualTo(listenPort.toInt())
+            }
+
+
+            it("should set proper kafka bootstrap servers") {
+                assertThat(result.kafkaBootstrapServers).isEqualTo(kafkaBootstrapServers)
+            }
+
+            it("should set proper kafka topics") {
+                assertThat(result.kafkaTopics).isEqualTo(
+                        setOf("top1", "top2")
+                )
+            }
+        }
+
+        given("some parameters are present in the short form") {
+
+            beforeEachTest {
+                result = cut.parseExpectingSuccess(
+                        "-p", listenPort,
+                        "--kafka-bootstrap-servers", kafkaBootstrapServers,
+                        "-f", kafkaTopics)
+            }
+
+            it("should set proper port") {
+                assertThat(result.apiPort).isEqualTo(listenPort.toInt())
+            }
+
+            it("should set proper kafka bootstrap servers") {
+                assertThat(result.kafkaBootstrapServers).isEqualTo(kafkaBootstrapServers)
+            }
+
+            it("should set proper kafka topics") {
+                assertThat(result.kafkaTopics).isEqualTo(
+                        setOf("top1", "top2")
+                )
+            }
+        }
+
+        describe("required parameter is absent") {
+            given("kafka topics are missing") {
+                it("should throw exception") {
+                    assertThat(cut.parseExpectingFailure(
+                            "-p", listenPort,
+                            "-s", kafkaBootstrapServers
+                    )).isInstanceOf(WrongArgumentError::class.java)
+                }
+            }
+
+            given("kafka bootstrap servers is missing") {
+                it("should throw exception") {
+                    assertThat(cut.parseExpectingFailure(
+                            "-p", listenPort,
+                            "-f", kafkaTopics
+                    )).isInstanceOf(WrongArgumentError::class.java)
+                }
+            }
+
+            given("listen port is missing") {
+                it("should throw exception") {
+                    assertThat(cut.parseExpectingFailure(
+                            "-p", listenPort,
+                            "-s", kafkaBootstrapServers
+                    )).isInstanceOf(WrongArgumentError::class.java)
+                }
+            }
+        }
+    }
+})
\ No newline at end of file