From b75b9ef415d61da6be68202880737ab5c459b760 Mon Sep 17 00:00:00 2001
From: Andrew Golovashevich <landgrafhomyak@gmail.com>
Date: Mon, 19 Aug 2024 05:23:00 +0300
Subject: [PATCH] [history] Scopes for transaction and prepared statement

---
 .../PreparedStatementPrepareAndFetch.kt       |  9 +++
 .../db/jdbc_kotlin_extensions/extensions.kt   | 56 +++++++++++++++++++
 2 files changed, 65 insertions(+)
 create mode 100644 src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/PreparedStatementPrepareAndFetch.kt
 create mode 100644 src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/extensions.kt

diff --git a/src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/PreparedStatementPrepareAndFetch.kt b/src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/PreparedStatementPrepareAndFetch.kt
new file mode 100644
index 0000000..6a4a4bd
--- /dev/null
+++ b/src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/PreparedStatementPrepareAndFetch.kt
@@ -0,0 +1,9 @@
+package ru.landgrafhomyak.db.jdbc_kotlin_extensions
+
+import java.sql.PreparedStatement
+import java.sql.ResultSet
+
+public interface PreparedStatementPrepareAndFetch<R> {
+    public fun prepare(ps: PreparedStatement)
+    public fun mapOne(rs: ResultSet): R
+}
\ No newline at end of file
diff --git a/src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/extensions.kt b/src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/extensions.kt
new file mode 100644
index 0000000..ba9ef0b
--- /dev/null
+++ b/src/jvmMain/kotlin/ru/landgrafhomyak/db/jdbc_kotlin_extensions/extensions.kt
@@ -0,0 +1,56 @@
+@file:JvmName("ExtensionsKt")
+@file:Suppress("SqlSourceToSinkFlow")
+@file:OptIn(ExperimentalContracts::class)
+
+package ru.landgrafhomyak.db.jdbc_kotlin_extensions
+
+import java.sql.Connection
+import java.sql.PreparedStatement
+import kotlin.contracts.ExperimentalContracts
+import kotlin.contracts.contract
+
+public fun <R> Connection.mapQuery(sql: String, action: PreparedStatementPrepareAndFetch<R>, to: MutableList<R>) {
+	this.prepareStatement(sql).use { ps ->
+		action.prepare(ps)
+		ps.executeQuery().use { rs ->
+			while (rs.next()) {
+				to.add(action.mapOne(rs))
+			}
+		}
+	}
+}
+
+public fun <R> Connection.mapQuery(sql: String, action: PreparedStatementPrepareAndFetch<R>): List<R> {
+	val out = ArrayList<R>()
+	this.mapQuery(sql, action, out)
+	return out
+}
+
+public inline fun <R> Connection.transaction(t: (Connection) -> R): R {
+	contract {
+		callsInPlace(t)
+	}
+
+	this.prepareStatement("BEGIN TRANSACTION").use { ps -> ps.executeUpdate() }
+	val r: R
+	try {
+		r = t(this)
+	} catch (e1: Throwable) {
+		try {
+			this.prepareStatement("ROLLBACK TRANSACTION").use { ps -> ps.executeUpdate() }
+		} catch (e2: Throwable) {
+			e1.addSuppressed(e2)
+		}
+		throw e1
+	}
+	this.prepareStatement("COMMIT TRANSACTION").use { ps -> ps.executeUpdate() }
+	return r
+}
+
+
+public inline fun <R> Connection.prepareStatement(sql: String, action: (PreparedStatement) -> R): R {
+	contract {
+		callsInPlace(action)
+	}
+	this.prepareStatement(sql).use { ps -> return action(ps) }
+}
\ No newline at end of file