Imporve code (#25)

* check for null

* remove redundant Users

Author: fractalliter

src/main/kotlin/com/personia/dao/user/UserDaoImpl.kt

@@ -17,8 +17,8 @@ class UserDaoImpl : UserDaoFacade {
 
     override suspend fun createUser(user: User): User? = dbQuery {
         val insertStatement = Users.insert {
-            it[Users.username] = user.username
-            it[Users.password] = user.password
+            it[username] = user.username
+            it[password] = user.password
         }
         insertStatement.resultedValues?.singleOrNull()?.let(::resultRowToNode)
     }

src/main/kotlin/com/personia/plugins/Authentication.kt

@@ -26,7 +26,7 @@ fun Application.configureAuthentication(config: ApplicationConfig) {
                     .build()
             )
             validate { credential ->
-                if (credential.payload.getClaim("username").asString() != "") {
+                if (!credential.payload.getClaim("username").asString().isNullOrEmpty()) {
                     JWTPrincipal(credential.payload)
                 } else {
                     null