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, 26 insertions, 18 deletions

diff --git a/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/api/MessageParametersParser.kt b/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/api/MessageParametersParser.kt
index 060f28a2..754fa31f 100644
--- a/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/api/MessageParametersParser.kt
+++ b/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/api/MessageParametersParser.kt
@@ -19,11 +19,13 @@
  */
 package org.onap.dcae.collectors.veshv.ves.message.generator.api
 
+import arrow.core.Either
+import arrow.core.Option
 import org.onap.dcae.collectors.veshv.ves.message.generator.impl.MessageParametersParserImpl
 import javax.json.JsonArray
 
 interface MessageParametersParser {
-    fun parse(request: JsonArray): List<MessageParameters>
+    fun parse(request: JsonArray): Either<ParsingError, List<MessageParameters>>
 
     companion object {
         val INSTANCE: MessageParametersParser by lazy {
@@ -31,3 +33,5 @@ interface MessageParametersParser {
         }
     }
 }
+
+data class ParsingError(val message: String, val cause: Option<Throwable>)
diff --git a/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/MessageParametersParserImpl.kt b/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/MessageParametersParserImpl.kt
index 5b328f1c..f3095618 100644
--- a/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/MessageParametersParserImpl.kt
+++ b/hv-collector-ves-message-generator/src/main/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/MessageParametersParserImpl.kt
@@ -19,9 +19,12 @@
  */
 package org.onap.dcae.collectors.veshv.ves.message.generator.impl
 
+import arrow.core.Option
+import arrow.core.Try
 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.dcae.collectors.veshv.ves.message.generator.api.ParsingError
 import javax.json.JsonArray
 
 /**
@@ -32,8 +35,8 @@ internal class MessageParametersParserImpl(
         private val commonEventHeaderParser: CommonEventHeaderParser = CommonEventHeaderParser()
 ) : MessageParametersParser {
 
-    override fun parse(request: JsonArray): List<MessageParameters> =
-            try {
+    override fun parse(request: JsonArray) =
+            Try {
                 request
                         .map { it.asJsonObject() }
                         .map {
@@ -41,13 +44,13 @@ internal class MessageParametersParserImpl(
                                     .parse(it.getJsonObject("commonEventHeader"))
                             val messageType = MessageType.valueOf(it.getString("messageType"))
                             val messagesAmount = it.getJsonNumber("messagesAmount")?.longValue()
-                                    ?: throw ParsingException("\"messagesAmount\" could not be parsed from message.",
-                                            NullPointerException())
+                                    ?: throw NullPointerException("\"messagesAmount\" could not be parsed from message.")
                             MessageParameters(commonEventHeader, messageType, messagesAmount)
                         }
-            } catch (e: Exception) {
-                throw ParsingException("Parsing request body failed", e)
+            }.toEither().mapLeft { ex ->
+                ParsingError(
+                        ex.message ?: "Unable to parse message parameters",
+                        Option.fromNullable(ex))
             }
 
-    internal class ParsingException(message: String, cause: Exception) : Exception(message, cause)
 }
diff --git a/hv-collector-ves-message-generator/src/test/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/impl/MessageParametersParserTest.kt b/hv-collector-ves-message-generator/src/test/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/impl/MessageParametersParserTest.kt
index 92561995..3b1a48b3 100644
--- a/hv-collector-ves-message-generator/src/test/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/impl/MessageParametersParserTest.kt
+++ b/hv-collector-ves-message-generator/src/test/kotlin/org/onap/dcae/collectors/veshv/ves/message/generator/impl/impl/MessageParametersParserTest.kt
@@ -20,13 +20,12 @@
 package org.onap.dcae.collectors.veshv.ves.message.generator.impl.impl
 
 import org.assertj.core.api.Assertions.assertThat
-import org.assertj.core.api.Assertions.assertThatExceptionOfType
+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.given
 import org.jetbrains.spek.api.dsl.it
 import org.jetbrains.spek.api.dsl.on
-import org.onap.dcae.collectors.veshv.ves.message.generator.impl.MessageParametersParserImpl.ParsingException
 import org.onap.dcae.collectors.veshv.ves.message.generator.api.MessageType
 import org.onap.dcae.collectors.veshv.ves.message.generator.impl.MessageParametersParserImpl
 
@@ -45,18 +44,20 @@ object MessageParametersParserTest : Spek({
                 it("should parse MessagesParameters object successfully") {
                     val result = messageParametersParser.parse(validMessagesParametesJson())
 
-                    assertThat(result).isNotNull
-                    assertThat(result).hasSize(2)
-                    val firstMessage = result.first()
-                    assertThat(firstMessage.messageType).isEqualTo(MessageType.VALID)
-                    assertThat(firstMessage.amount).isEqualTo(EXPECTED_MESSAGES_AMOUNT)
+                    result.fold({ fail("should have succeeded") }) { rightResult ->
+                        assertThat(rightResult).hasSize(2)
+                        val firstMessage = rightResult.first()
+                        assertThat(firstMessage.messageType).isEqualTo(MessageType.VALID)
+                        assertThat(firstMessage.amount).isEqualTo(EXPECTED_MESSAGES_AMOUNT)
+
+                    }
                 }
             }
+
             on("invalid parameters json") {
                 it("should throw exception") {
-                    assertThatExceptionOfType(ParsingException::class.java).isThrownBy {
-                        messageParametersParser.parse(invalidMessagesParametesJson())
-                    }
+                    val result = messageParametersParser.parse(invalidMessagesParametesJson())
+                    assertThat(result.isLeft()).describedAs("is left").isTrue()
                 }
             }
         }