Use IO monad when starting servers

Change-Id: I3e97161535fc721dda6109c4cb5f23a1db0afde3
Signed-off-by: Piotr Jaszczyk <piotr.jaszczyk@nokia.com>
Issue-ID: DCAEGEN2-601

2 files changed, 22 insertions, 25 deletions

diff --git a/hv-collector-client-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/xnf/main.kt b/hv-collector-client-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/xnf/main.kt
index dbeba2b2..63c48757 100644
--- a/hv-collector-client-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/xnf/main.kt
+++ b/hv-collector-client-simulator/src/main/kotlin/org/onap/dcae/collectors/veshv/simulators/xnf/main.kt
@@ -19,38 +19,36 @@
  */
 package org.onap.dcae.collectors.veshv.simulators.xnf
 
-import arrow.core.Failure
-import arrow.core.Success
 import org.onap.dcae.collectors.veshv.simulators.xnf.config.ArgBasedClientConfiguration
 import org.onap.dcae.collectors.veshv.simulators.xnf.impl.HttpServer
 import org.onap.dcae.collectors.veshv.simulators.xnf.impl.VesHvClient
-import org.onap.dcae.collectors.veshv.utils.commandline.handleErrorsInMain
+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.commandline.handleWrongArgumentErrorCurried
 import org.onap.dcae.collectors.veshv.utils.logging.Logger
+import org.slf4j.LoggerFactory
 
-
-private val logger = Logger("Simulator :: main")
-private const val PROGRAM_NAME = "java org.onap.dcae.collectors.veshv.main.MainKt"
+private const val PACKAGE_NAME = "org.onap.dcae.collectors.veshv.simulators.xnf"
+private val logger = Logger(PACKAGE_NAME)
+const val PROGRAM_NAME = "java $PACKAGE_NAME.MainKt"
 
 /**
  * @author Jakub Dudycz <jakub.dudycz@nokia.com>
  * @since June 2018
  */
-fun main(args: Array<String>) {
-    val httpServer = ArgBasedClientConfiguration().parse(args)
+fun main(args: Array<String>) =
+    ArgBasedClientConfiguration().parse(args)
+            .mapLeft(handleWrongArgumentErrorCurried(PROGRAM_NAME))
             .map(::VesHvClient)
             .map(::HttpServer)
-
-    when (httpServer) {
-        is Success -> httpServer.value.start().unsafeRunAsync {
-            it.fold(
+            .map { it.start().void() }
+            .unsafeRunEitherSync(
                     { ex ->
                         logger.error("Failed to start a server", ex)
+                        ExitFailure(1)
                     },
-                    { srv ->
-                        logger.info("Started Simulator API server (listening on ${srv.bindHost}:${srv.bindPort})")
+                    {
+                        logger.info("Started xNF Simulator API server")
                     }
             )
-        }
-        is Failure -> httpServer.handleErrorsInMain(PROGRAM_NAME, logger)
-    }
-}
diff --git a/hv-collector-client-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/main/config/ArgBasedClientConfigurationTest.kt b/hv-collector-client-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/main/config/ArgBasedClientConfigurationTest.kt
index 2746c0a6..3b1836eb 100644
--- a/hv-collector-client-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/main/config/ArgBasedClientConfigurationTest.kt
+++ b/hv-collector-client-simulator/src/test/kotlin/org/onap/dcae/collectors/veshv/main/config/ArgBasedClientConfigurationTest.kt
@@ -21,6 +21,7 @@ package org.onap.dcae.collectors.veshv.main.config
 
 import arrow.core.Failure
 import arrow.core.Success
+import arrow.core.identity
 import org.assertj.core.api.Assertions.assertThat
 import org.jetbrains.spek.api.Spek
 import org.jetbrains.spek.api.dsl.describe
@@ -46,13 +47,11 @@ object ArgBasedClientConfigurationTest : Spek({
         cut = ArgBasedClientConfiguration()
     }
 
-    fun parse(vararg cmdLine: String): ClientConfiguration {
-        val result = cut.parse(cmdLine)
-        return when (result) {
-            is Success -> result.value
-            is Failure -> throw AssertionError("Parsing result should be present")
-        }
-    }
+    fun parse(vararg cmdLine: String): ClientConfiguration =
+            cut.parse(cmdLine).fold(
+                    {throw AssertionError("Parsing result should be present")},
+                    ::identity
+            )
 
     describe("parsing arguments") {
         lateinit var result: ClientConfiguration