Refactor settings loader

src/main/kotlin/App.kt

@@ -32,7 +32,7 @@ class App {
                     SftpClient(settings.sftpSettings).use { sftp ->
                         val validator = FileValidation(sftp)
 
-                        val files = sftp.listFiles(settings.appSettings["directory"].orEmpty()).map { File(it) }
+                        val files = sftp.listFiles(settings.appSettings.getProperty("directory")).map { File(it) }
 
                         for (file in files) {
                             val report = validator.validate(file)

src/main/kotlin/SettingsLoader.kt

@@ -51,14 +51,15 @@ class SettingsLoader {
 
     private val rawKafkaProperties: Map<String, String>
     val topic: String
-    val appSettings: Map<String, String>
-    val sftpSettings: Map<String, String>
+    val appSettings = Properties()
+    val sftpSettings = Properties()
     val kafkaProducerProperties = Properties()
+    val mappedYaml: Map<String, Any>
 
     init {
         try {
             val rawYaml = loadYaml()
-            val mappedYaml = rawYaml as Map<String, Any>
+            mappedYaml = rawYaml as Map<String, Any>
             val kafkaOptions = mappedYaml["kafka"] as Map<String, Any>
             val topics = kafkaOptions["topic"] as Map<String, String>
             topic = topics["out"].orEmpty()
@@ -67,15 +68,13 @@ class SettingsLoader {
             }
             rawKafkaProperties = kafkaOptions["producer"] as Map<String, String>
 
-            appSettings = rawYaml["app"] as Map<String, String>
-            ensurePropertyIsSet("directory", appSettings)
+            appSettings.setProperty("directory", addSetting("app", "directory"))
 
-            sftpSettings = rawYaml["sftp"] as Map<String, String>
-            ensurePropertyIsSet("host", sftpSettings)
-            ensurePropertyIsSet("port", sftpSettings)
-            ensurePropertyIsSet("user", sftpSettings)
-            ensurePropertyIsSet("password", sftpSettings)
-            ensurePropertyIsSet("fingerprint", sftpSettings)
+            sftpSettings.setProperty("host", addSetting("sftp", "host"))
+            sftpSettings.setProperty("port", addSetting("sftp", "port"))
+            sftpSettings.setProperty("user", addSetting("sftp", "user"))
+            sftpSettings.setProperty("password", addSetting("sftp", "password"))
+            sftpSettings.setProperty("fingerprint", addSetting("sftp", "fingerprint"))
         } catch (ex: ClassCastException) {
             ex.printStackTrace()
             log.error("The properties file has an invalid structure: $ex")
@@ -87,9 +86,16 @@ class SettingsLoader {
         initializeKafkaProperties()
     }
 
-    private fun ensurePropertyIsSet(setting: String, settings: Map<String, String>) {
-        if (settings[setting].isNullOrEmpty()) {
-            throw MissingSettingException("missing", setting)
+    private fun addSetting(base: String, setting: String): String {
+        val settings = mappedYaml[base] as Map<String, Any>
+        if (settings.containsKey(setting)) {
+            return when (val value = settings[setting]) {
+                is String -> if (value.isNotEmpty()) value else throw MissingSettingException("missing", "$base.$setting")
+                is Int -> value.toString()
+                else -> throw MissingSettingException("missing", "$base.$setting")
+            }
+        } else {
+            throw MissingSettingException("missing", "$base.$setting")
         }
     }
 

src/main/kotlin/SftpClient.kt

@@ -22,6 +22,7 @@ import java.io.Closeable
 import java.io.File
 import java.net.ConnectException
 import java.net.UnknownHostException
+import java.util.Properties
 import kotlin.system.exitProcess
 import net.schmizz.sshj.SSHClient
 import net.schmizz.sshj.sftp.FileAttributes
@@ -32,16 +33,16 @@ import net.schmizz.sshj.sftp.SFTPClient
 import net.schmizz.sshj.userauth.UserAuthException
 import org.apache.logging.log4j.LogManager
 
-class SftpClient(sftpSettings: Map<String, String>) : Closeable {
+class SftpClient(sftpSettings: Properties) : Closeable {
     private val log = LogManager.getLogger("SftpClient")
     private val ssh = SSHClient()
     private val instance: SFTPClient
     init {
         try {
             ssh.loadKnownHosts()
-            ssh.addHostKeyVerifier(sftpSettings["fingerprint"])
-            ssh.connect(sftpSettings["host"])
-            ssh.authPassword(sftpSettings["user"], sftpSettings["password"])
+            ssh.addHostKeyVerifier(sftpSettings.getProperty("fingerprint"))
+            ssh.connect(sftpSettings.getProperty("host"))
+            ssh.authPassword(sftpSettings.getProperty("user"), sftpSettings.getProperty("password"))
             instance = ssh.newSFTPClient()
         } catch (ex: UserAuthException) {
             log.error("SFTP User Authentication Error: Invalid user authentication supplied.")