[#1] Added a reactive transaction example

jOOQ-demo-pro/jOOQ-demo-kotlin/src/test/kotlin/org/jooq/demo/kotlin/Demo13Reactive.kt

@@ -1,7 +1,10 @@
 package org.jooq.demo.kotlin
 
+import kotlinx.coroutines.reactive.awaitFirst
 import kotlinx.coroutines.reactive.awaitFirstOrNull
+import kotlinx.coroutines.reactor.mono
 import kotlinx.coroutines.runBlocking
+import org.jooq.Configuration
 import org.jooq.Records.mapping
 import org.jooq.demo.AbstractDemo
 import org.jooq.demo.kotlin.db.tables.records.ActorRecord
@@ -81,9 +84,44 @@ class Demo13Reactive : AbstractDemo() {
         return ctx
             .selectFrom(ACTOR)
             .where(ACTOR.ACTOR_ID.eq(id))
+
+            // Turn any reactive streams Publisher<T> into a suspension result using the
+            // kotlinx-coroutines-reactive extensions
             .awaitFirstOrNull()
     }
 
+    @Test
+    fun coroutinesWithTransactions() {
+        val actor: ActorRecord = runBlocking {
+            insertActorTransaction()
+        }
+
+        println(actor)
+    }
+
+    suspend fun insertActorTransaction(): ActorRecord {
+        return ctx.transactionPublisher { c ->
+
+            // Turn the suspension result into a Mono, which implements the reactive
+            // streams Publisher<T> SPI, which jOOQ expects as a result from a
+            // TransactionalPublishable
+            mono {
+                insertActor(c)
+            }
+        }
+
+        // Turn the Publisher<T> that is returned from transactionPublisher() back
+        // into a suspension result
+        .awaitFirst();
+    }
+
+    suspend fun insertActor(c: Configuration): ActorRecord = ctx.transactionPublisher { c -> c.dsl()
+        .insertInto(ACTOR)
+        .columns(ACTOR.ACTOR_ID, ACTOR.FIRST_NAME, ACTOR.LAST_NAME)
+        .values(201L, "A", "A")
+        .returning()
+    }.awaitFirst()
+
     @After
     override fun teardown() {
         cleanup(ACTOR, ACTOR.ACTOR_ID)