sample mono / flux handling

Author: renatomrcosta

src/test/kotlin/com/xunfos/r2dbpointissue/HandlingTests.kt

@@ -0,0 +1,49 @@
+package com.xunfos.r2dbpointissue
+
+import com.xunfos.r2dbpointissue.repository.PointyTable
+import com.xunfos.r2dbpointissue.repository.PointyTableRepository
+import io.r2dbc.postgresql.codec.Point
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.collect
+import kotlinx.coroutines.flow.flowOf
+import kotlinx.coroutines.reactive.asFlow
+import kotlinx.coroutines.reactive.asPublisher
+import kotlinx.coroutines.reactive.awaitFirstOrNull
+import kotlinx.coroutines.reactive.awaitSingle
+import kotlinx.coroutines.runBlocking
+import org.junit.jupiter.api.Test
+import org.springframework.boot.test.context.SpringBootTest
+import java.util.UUID
+
+@SpringBootTest
+class HandlingTests(
+    private val repository: PointyTableRepository,
+) {
+    @Test
+    fun `simple showcase of dealing with futures and fluxes`() = runBlocking {
+        // Value already exists in the db, my entity is called PointyTable. Don't ask
+        val find: PointyTable = repository.findById(
+            UUID.fromString("0679a290-8015-473d-b4f4-3bbff0c35fdb")
+        ).awaitSingle()
+
+        val findOrNull: PointyTable = repository.findById(
+            UUID.randomUUID()
+        ).awaitFirstOrNull() ?: getRandomValue() // you can write custom behavior here!
+
+        val findMany: Flow<PointyTable> = repository.findAll().asFlow()
+
+        val flowOfEntities: Flow<PointyTable> = flowOf(getRandomValue(), getRandomValue())
+        val savedValues = repository.saveAll(flowOfEntities.asPublisher()).asFlow()
+
+        //operating / collecting
+        savedValues.collect {
+            println("My Saved Values: $it")
+        }
+    }
+
+    private fun getRandomValue(): PointyTable = PointyTable(
+        id = UUID.randomUUID(),
+        description = "Some description",
+        location = Point.of(1.0, 2.2),
+    )
+}