Close active connection before creating new one

src/main/kotlin/io/tcds/orm/connection/ReconnectableConnection.kt

@@ -0,0 +1,27 @@
+package io.tcds.orm.connection
+
+import org.slf4j.Logger
+import java.sql.Connection
+
+class ReconnectableConnection(
+    private val logger: Logger? = null,
+    private val factory: () -> Connection,
+) : ResilientConnection {
+    private var connection: Connection? = null
+
+    override fun instance(): Connection {
+        val status = listOf(
+            connection == null,
+            connection?.isClosed,
+            connection?.isValid(5) == false,
+        )
+        val requiresCreation = status.any { it == true }
+
+        if (requiresCreation) {
+            connection?.close().apply { logger?.info("Closed active connection") }
+            connection = factory().apply { logger?.info("Created new connection") }
+        }
+
+        return connection!!
+    }
+}

src/main/kotlin/io/tcds/orm/connection/ResilientConnection.kt

@@ -1,12 +1,13 @@
 package io.tcds.orm.connection
 
+import org.slf4j.Logger
 import java.sql.Connection
 import java.sql.Connection as JdbcConnection
 
 interface ResilientConnection {
     fun instance(): JdbcConnection
 
     companion object {
-        fun reconnectable(factory: () -> Connection) = ReconnectableResilientConnection(factory)
+        fun reconnectable(logger: Logger? = null, factory: () -> Connection) = ReconnectableConnection(logger, factory)
     }
 }

src/test/kotlin/fixtures/connection/ReconnectableResilientConnectionTest.kt → src/test/kotlin/fixtures/connection/ReconnectableConnectionTest.kt

@@ -1,19 +1,24 @@
 package fixtures.connection
 
-import io.mockk.every
-import io.mockk.mockk
+import io.mockk.*
 import io.tcds.orm.connection.ResilientConnection
 import org.junit.jupiter.api.Assertions
 import org.junit.jupiter.api.Test
+import org.slf4j.Logger
 import java.sql.Connection as JdbcConnection
 
-class ReconnectableResilientConnectionTest {
+class ReconnectableConnectionTest {
+    private val logger = mockk<Logger>()
     private val connection = mockk<JdbcConnection>()
     private var calls = 0
 
+    init {
+        every { logger.info(any()) } just runs
+    }
+
     @Test
     fun `when instance is null then create from the factory`() {
-        val connection = ResilientConnection.reconnectable {
+        val connection = ResilientConnection.reconnectable(logger) {
             calls++
             connection
         }
@@ -22,13 +27,15 @@ class ReconnectableResilientConnectionTest {
 
         Assertions.assertEquals(1, calls)
         Assertions.assertInstanceOf(JdbcConnection::class.java, instance)
+        verify(exactly = 1) { logger.info("Created new connection") }
     }
 
     @Test
     fun `when instance is closed then create from the factory`() {
         every { connection.isClosed } returns true
         every { connection.isValid(any()) } returns true
-        val connection = ResilientConnection.reconnectable {
+        every { connection.close() } just runs
+        val connection = ResilientConnection.reconnectable(logger) {
             calls++
             connection
         }
@@ -39,13 +46,25 @@ class ReconnectableResilientConnectionTest {
 
         Assertions.assertEquals(3, calls)
         Assertions.assertInstanceOf(JdbcConnection::class.java, instance)
+        verifySequence {
+            // first
+            logger.info("Closed active connection")
+            logger.info("Created new connection")
+            // second
+            logger.info("Closed active connection")
+            logger.info("Created new connection")
+            // third
+            logger.info("Closed active connection")
+            logger.info("Created new connection")
+        }
     }
 
     @Test
     fun `when instance is not valid then create from the factory`() {
         every { connection.isClosed } returns false
         every { connection.isValid(any()) } returns false
-        val connection = ResilientConnection.reconnectable {
+        every { connection.close() } just runs
+        val connection = ResilientConnection.reconnectable(logger) {
             calls++
             connection
         }
@@ -56,5 +75,16 @@ class ReconnectableResilientConnectionTest {
 
         Assertions.assertEquals(3, calls)
         Assertions.assertInstanceOf(JdbcConnection::class.java, instance)
+        verifySequence {
+            // first
+            logger.info("Closed active connection")
+            logger.info("Created new connection")
+            // second
+            logger.info("Closed active connection")
+            logger.info("Created new connection")
+            // third
+            logger.info("Closed active connection")
+            logger.info("Created new connection")
+        }
     }
 }