[UPDATE] Code cleanup and proper separation of code.

Also added DB host config

Author: hossain-khan

sample-local.properties

@@ -3,6 +3,7 @@
 # ----------------------------------------------------
 
 ## Data based properties
+db_host=localhost:
 db_name=YourDbName
 db_username=your_db_username
 db_password=your_db_password

src/main/kotlin/dev/hossain/postgresqldelight/AppConfig.kt

@@ -1,3 +1,15 @@
 package dev.hossain.postgresqldelight
 
-data class AppConfig(val dbName: String, val dbUsername: String, val dbPassword: String)
+/**
+ * App configuration data.
+ */
+data class AppConfig(
+    /**
+     * Database host with port.
+     * See https://jdbc.postgresql.org/documentation/use/
+     */
+    val dbHost: String,
+    val dbName: String,
+    val dbUsername: String,
+    val dbPassword: String,
+)

src/main/kotlin/dev/hossain/postgresqldelight/AppConfigLoader.kt

@@ -10,6 +10,7 @@ class AppConfigLoader {
     fun loadAppConfig(): AppConfig {
         val properties = Properties().apply { load(File("local.properties").inputStream()) }
         return AppConfig(
+            dbHost = properties.getProperty("db_host"),
             dbName = properties.getProperty("db_name"),
             dbUsername = properties.getProperty("db_username"),
             dbPassword = properties.getProperty("db_password"),

src/main/kotlin/dev/hossain/postgresqldelight/Main.kt

@@ -1,39 +1,34 @@
 package dev.hossain.postgresqldelight
 
-import app.cash.sqldelight.db.SqlDriver
-import app.cash.sqldelight.driver.jdbc.asJdbcDriver
 import io.github.serpro69.kfaker.Faker
 import io.github.serpro69.kfaker.faker
-import javax.sql.DataSource
 import kotlin.math.absoluteValue
 import kotlin.random.Random
 
 
+/**
+ * Test application entry point. Run the app with ▶️ icon from left gutter.
+ */
 fun main(args: Array<String>) {
     println("Begin SQLDelight 2.0 with PostgreSQL Sample!")
-    val appConfigLoader = AppConfigLoader()
+    val appConfig: AppConfig = AppConfigLoader().loadAppConfig()
     val sportsRepository = SportsRepository()
-    val dataSource: DataSource = sportsRepository.getSource(appConfigLoader.loadAppConfig())
-
-
-    val driver: SqlDriver = dataSource.asJdbcDriver()
-    SportsDatabase.Schema.create(driver)
+    val playerQueries: PlayerQueries = sportsRepository.getPlayerQueries(appConfig)
 
-    testDriveDatabase(driver, faker { })
+    testDriveDatabase(playerQueries, faker { })
 }
 
 
 /**
- * @param driver the [SqlDriver] required to create the database.
+ * Test drives different functions from [PlayerQueries].
+ *
+ * @param playerQueries SQLDelight class for doing player queries
  * @param faker Fake data generator.
  */
-fun testDriveDatabase(driver: SqlDriver, faker: Faker) {
-    val database = SportsDatabase(driver)
-
-    val playerQueries: PlayerQueries = database.playerQueries
-
+fun testDriveDatabase(playerQueries: PlayerQueries, faker: Faker) {
     // Show all players
-    println(playerQueries.selectAll().executeAsList())
+    val hockeyPlayers = playerQueries.selectAll().executeAsList()
+    println("Existing ${hockeyPlayers.size} records: $hockeyPlayers")
 
 
     // Uses query param to insert data
@@ -49,4 +44,7 @@ fun testDriveDatabase(driver: SqlDriver, faker: Faker) {
         full_name = faker.name.name()
     )
     playerQueries.insertFullPlayerObject(player)
+
+    val totalRecords = playerQueries.totalRecords().executeAsOne()
+    println("Total players: $totalRecords.")
 }

src/main/kotlin/dev/hossain/postgresqldelight/SportsRepository.kt

@@ -1,17 +1,42 @@
 package dev.hossain.postgresqldelight
 
+import app.cash.sqldelight.db.SqlDriver
+import app.cash.sqldelight.driver.jdbc.asJdbcDriver
 import com.zaxxer.hikari.HikariConfig
 import com.zaxxer.hikari.HikariDataSource
 import javax.sql.DataSource
 
+/**
+ * Repository for creating database and getting SQLDelight classes needed for testing.
+ */
 class SportsRepository constructor(
 
 ) {
 
-    fun getSource(appConfig: AppConfig): DataSource {
+    fun getPlayerQueries(appConfig: AppConfig): PlayerQueries {
+        val dataSource: DataSource = getDataSource(appConfig)
+
+        val driver: SqlDriver = dataSource.asJdbcDriver()
+        
+        execSchema(driver)
+
+        val database = SportsDatabase(driver)
+        val playerQueries: PlayerQueries = database.playerQueries
+
+        return playerQueries
+    }
+
+    /**
+     * @param driver the [SqlDriver] required to create the database.
+     */
+    private fun execSchema(driver: SqlDriver) {
+        SportsDatabase.Schema.create(driver)
+    }
+
+    private fun getDataSource(appConfig: AppConfig): DataSource {
         val hikariConfig = HikariConfig()
         // https://jdbc.postgresql.org/documentation/use/
-        hikariConfig.setJdbcUrl("jdbc:postgresql://192.168.2.32:5432/${appConfig.dbName}")
+        hikariConfig.setJdbcUrl("jdbc:postgresql://${appConfig.dbHost}/${appConfig.dbName}")
         hikariConfig.driverClassName = "org.postgresql.Driver"
         hikariConfig.username = appConfig.dbUsername
         hikariConfig.password = appConfig.dbPassword

src/main/sqldelight/dev/hossain/postgresqldelight/Player.sq

@@ -19,6 +19,8 @@ insertFullPlayerObject:
 INSERT INTO hockeyPlayer(player_number, full_name)
 VALUES ?;
 
+totalRecords:
+SELECT count(*) AS total_rows FROM hockeyPlayer;
 
 -- tableExists:
 -- https://database.guide/5-ways-to-check-if-a-table-exists-in-postgresql/