ad tests

src/test/kotlin/com/example/demo/services/kafka/ProducerImplTest.kt

@@ -0,0 +1,60 @@
+package com.example.demo.services.kafka
+
+import com.example.demo.models.Product
+import com.example.demo.services.kafka.dto.ProductDto
+import org.junit.runner.RunWith
+import org.mockito.kotlin.argumentCaptor
+import org.mockito.kotlin.doReturn
+import org.mockito.kotlin.whenever
+import org.springframework.beans.factory.annotation.Autowired
+import org.springframework.boot.test.context.SpringBootTest
+import org.springframework.boot.test.mock.mockito.MockBean
+import org.springframework.kafka.core.KafkaTemplate
+import org.springframework.kafka.support.KafkaHeaders
+import org.springframework.kafka.support.SendResult
+import org.springframework.messaging.Message
+import org.springframework.test.context.junit4.SpringRunner
+import java.time.OffsetDateTime
+import java.util.*
+import java.util.concurrent.CompletableFuture
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+@RunWith(SpringRunner::class)
+@SpringBootTest
+class ProducerImplTest {
+    @Autowired
+    private lateinit var producerImpl: ProducerImpl
+
+    @MockBean
+    private lateinit var kafkaTemplate: KafkaTemplate<String, Any>
+
+    @Test
+    fun produceProductInfo_success() {
+        val topic = "some-topic"
+        val product = Product(
+            id = 123,
+            guid = UUID.randomUUID(),
+            name = "name",
+            description = null,
+            price = 10050,
+            createdAt = OffsetDateTime.now().minusDays(2),
+            updatedAt = OffsetDateTime.now().minusHours(1),
+            deletedAt = OffsetDateTime.now(),
+        )
+
+        val captor = argumentCaptor<Message<ProductDto>>()
+
+        whenever(kafkaTemplate.send(captor.capture()))
+            .doReturn(CompletableFuture<SendResult<String, Any>>())
+
+        producerImpl.produceProductInfo(topic, product)
+
+        assertEquals(1, captor.allValues.count())
+        val actualArgument = captor.firstValue
+        assertEquals(product.id, actualArgument.payload.id)
+        assertEquals(product.guid.toString(), actualArgument.payload.guid)
+        assertEquals(topic, actualArgument.headers[KafkaHeaders.TOPIC])
+        assertEquals("some-custom-header", actualArgument.headers["X-Custom-Header"])
+    }
+}