Improve coverage of xNF simulator

Also refactor to make it possible.

Change-Id: I6da6d3f33e57c524a7e353ecebd3e045d8ceed2a
Issue-ID: DCAEGEN2-739
Signed-off-by: Piotr Jaszczyk <piotr.jaszczyk@nokia.com>

3 files changed, 44 insertions, 69 deletions

diff --git a/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt b/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt
index 239f7102..354edaeb 100644
--- a/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt
+++ b/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/MessageStreamValidation.kt
@@ -54,10 +54,14 @@ class MessageStreamValidation(
         val expectations = Json.createReader(input).readArray()
         val messageParams = messageParametersParser.parse(expectations)
 
-        if (messageParams.isEmpty())
-            throw IllegalArgumentException("Message param list cannot be empty")
-
-        return messageParams
+        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>) =
diff --git a/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/ApiServer.kt b/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/DcaeAppApiServer.kt
index 6c830b9d..1eca9317 100644
--- a/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/ApiServer.kt
+++ b/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/impl/adapters/DcaeAppApiServer.kt
@@ -19,18 +19,14 @@
  */
 package org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.adapters
 
-import arrow.core.Left
-import arrow.core.Right
 import arrow.effects.IO
-import arrow.effects.fix
-import arrow.effects.monad
-import arrow.typeclasses.binding
 import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.DcaeAppSimulator
-import org.onap.dcae.collectors.veshv.utils.logging.Logger
-import ratpack.exec.Promise
+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.handling.Context
-import ratpack.http.Response
 import ratpack.server.RatpackServer
 import ratpack.server.ServerConfig
 
@@ -38,7 +34,21 @@ import ratpack.server.ServerConfig
  * @author Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
  * @since May 2018
  */
-class ApiServer(private val simulator: DcaeAppSimulator) {
+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> =
@@ -52,10 +62,10 @@ class ApiServer(private val simulator: DcaeAppSimulator) {
     private fun setupHandlers(chain: Chain) {
         chain
                 .put("configuration/topics") { ctx ->
-                    val operation = ctx.bodyIo().flatMap { body ->
-                        simulator.listenToTopics(body.text)
+                    ctx.request.body.then { body ->
+                        val operation = simulator.listenToTopics(body.text)
+                        ctx.response.sendOrError(operation)
                     }
-                    ctx.response.sendOrError(operation)
 
                 }
                 .delete("messages") { ctx ->
@@ -64,7 +74,7 @@ class ApiServer(private val simulator: DcaeAppSimulator) {
                 }
                 .get("messages/all/count") { ctx ->
                     simulator.state().fold(
-                            { ctx.response.status(STATUS_NOT_FOUND) },
+                            { ctx.response.status(HttpConstants.STATUS_NOT_FOUND) },
                             {
                                 ctx.response
                                         .contentType(CONTENT_TEXT)
@@ -72,58 +82,20 @@ class ApiServer(private val simulator: DcaeAppSimulator) {
                             })
                 }
                 .post("messages/all/validate") { ctx ->
-                    val responseStatus = IO.monad().binding {
-                        val body = ctx.bodyIo().bind()
-                        val isValid = simulator.validate(body.inputStream).bind()
-                        if (isValid)
-                            STATUS_OK
-                        else
-                            STATUS_BAD_REQUEST
-                    }.fix()
-
-                    ctx.response.sendStatusOrError(responseStatus)
+                    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(STATUS_OK).send()
+                    ctx.response.status(HttpConstants.STATUS_OK).send()
                 }
     }
 
-    private fun Context.bodyIo() = request.body.asIo()
-
-    private fun <T> Promise<T>.asIo(): IO<T> = IO.async { emitResult ->
-        onError {
-            emitResult(Left(it))
-        }.then { result ->
-            emitResult(Right(result))
-        }
-    }
-
-    private fun Response.sendOrError(responseStatus: IO<Unit>) {
-        sendStatusOrError(responseStatus.map { STATUS_OK })
-    }
-
-    private fun Response.sendStatusOrError(responseStatus: IO<Int>) {
-        responseStatus.unsafeRunAsync { cb ->
-            cb.fold(
-                    { err ->
-                        logger.warn("Error occurred. Sending HTTP$STATUS_INTERNAL_SERVER_ERROR.", err)
-                        status(ApiServer.STATUS_INTERNAL_SERVER_ERROR)
-                                .send(CONTENT_TEXT, err.message)
-                    },
-                    {
-                        status(it).send()
-                    }
-            )
-        }
-    }
-
     companion object {
-        private val logger = Logger(ApiServer::class)
         private const val CONTENT_TEXT = "text/plain"
-
-        private const val STATUS_OK = 200
-        private const val STATUS_BAD_REQUEST = 400
-        private const val STATUS_NOT_FOUND = 404
-        private const val STATUS_INTERNAL_SERVER_ERROR = 500
     }
 }
diff --git a/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt b/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt
index a65a2686..c0f8b340 100644
--- a/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt
+++ b/hv-collector-dcae-app-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/dcaeapp/main.kt
@@ -24,11 +24,10 @@ import org.onap.dcae.collectors.veshv.simulators.dcaeapp.impl.config.ArgDcaeAppS
 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.ApiServer
+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.void
+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
 
@@ -52,7 +51,7 @@ fun main(args: Array<String>) =
 
 
 private fun startApp(config: DcaeAppSimConfiguration): IO<Unit> {
-    return ApiServer(DcaeAppSimulator(ConsumerFactory(config.kafkaBootstrapServers)))
+    return DcaeAppApiServer(DcaeAppSimulator(ConsumerFactory(config.kafkaBootstrapServers)))
             .start(config.apiPort, config.kafkaTopics)
-            .void()
+            .unit()
 }