update TestClient to allow @MockBean usage (#6311)

airbyte-featureflag/src/main/kotlin/Client.kt

@@ -13,6 +13,8 @@ import com.launchdarkly.sdk.LDContext
 import com.launchdarkly.sdk.server.LDClient
 import io.micronaut.context.annotation.Property
 import io.micronaut.context.annotation.Requires
+import io.micronaut.context.annotation.Secondary
+import jakarta.inject.Inject
 import jakarta.inject.Singleton
 import org.slf4j.LoggerFactory
 import java.lang.Thread.MIN_PRIORITY
@@ -149,15 +151,28 @@ class LaunchDarklyClient(private val client: LDClient) : FeatureFlagClient {
 }
 
 /**
- * Test feature-flag client.
+ * Test feature-flag client. Only to be used in test scenarios.
  *
- * Intended only for usage in testing scenarios. Can also be mocked in unit tests.
+ * This class can be mocked and can also be used with Micronaut's @MockBean annotation to replace the [FeatureFlagClient] dependency.
+ *
+ * To use with the @MockBean annotation define the following method within your @MicronautTest annotated test class:
+ * ```java
+ * @MockBean(FeatureFlagClient.class)
+ * TestClient featureFlagClient() {
+ *   return mock(TestClient.class);
+ * }
+ * ```
  *
  * All [Flag] instances will use the provided [values] map as their source of truth, including [EnvVar] flags.
  *
  * @param [values] is a map of [Flag.key] to its status.
  */
-class TestClient @JvmOverloads constructor(val values: Map<String, Any> = mapOf()) : FeatureFlagClient {
+@Secondary
+open class TestClient(val values: Map<String, Any>) : FeatureFlagClient {
+
+  @Inject
+  constructor() : this(mapOf())
+
   override fun boolVariation(flag: Flag<Boolean>, context: Context): Boolean {
     return when (flag) {
       is EnvVar -> {

airbyte-featureflag/src/test/kotlin/ClientTest.kt

@@ -8,6 +8,7 @@ import com.launchdarkly.sdk.server.LDClient
 import io.micronaut.context.annotation.Bean
 import io.micronaut.context.annotation.Property
 import io.micronaut.context.annotation.Replaces
+import io.micronaut.test.annotation.MockBean
 import io.micronaut.test.extensions.junit5.annotation.MicronautTest
 import io.mockk.called
 import io.mockk.clearMocks
@@ -16,6 +17,7 @@ import io.mockk.mockk
 import io.mockk.slot
 import io.mockk.verify
 import jakarta.inject.Inject
+import jakarta.inject.Singleton
 import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Test
 import java.nio.file.Path
@@ -26,7 +28,6 @@ import kotlin.io.path.writeText
 import kotlin.test.Ignore
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
-import kotlin.test.assertNotNull
 import kotlin.test.assertTrue
 
 /** workspaceId used across multiple tests */
@@ -404,27 +405,24 @@ class InjectTest {
   }
 
   @Inject
-  var featureFlagClient: FeatureFlagClient? = null
+  lateinit var featureFlagClient: FeatureFlagClient
 
   @Test
   fun `ConfigFileClient loads if no client property defined`() {
-    assertNotNull(featureFlagClient)
     assertTrue { featureFlagClient is ConfigFileClient }
     assertTrue { featureFlagClient?.boolVariation(flag, context) ?: false }
   }
 
   @Property(name = CONFIG_FF_CLIENT, value = "")
   @Test
   fun `ConfigFileClient loads if client property is empty`() {
-    assertNotNull(featureFlagClient)
     assertTrue { featureFlagClient is ConfigFileClient }
     assertTrue { featureFlagClient?.boolVariation(flag, context) ?: false }
   }
 
   @Property(name = CONFIG_FF_CLIENT, value = "not-launchdarkly")
   @Test
   fun `ConfigFileClient loads if client property is not ${CONFIG_FF_CLIENT_VAL_LAUNCHDARKLY}`() {
-    assertNotNull(featureFlagClient)
     assertTrue { featureFlagClient is ConfigFileClient }
     assertTrue { featureFlagClient?.boolVariation(flag, context) ?: false }
   }
@@ -434,8 +432,38 @@ class InjectTest {
   fun `LaunchDarklyClient loads if client is defined as ${CONFIG_FF_CLIENT_VAL_LAUNCHDARKLY}`() {
     every { ldClient.boolVariation(flag.key, any<LDContext>(), flag.default) } returns flag.default
 
-    assertNotNull(featureFlagClient)
     assertTrue { featureFlagClient is LaunchDarklyClient }
     assertTrue { featureFlagClient?.boolVariation(flag, context) ?: false }
   }
 }
+
+@MicronautTest(rebuildContext = true)
+class NonMockBeanTest {
+  @Singleton
+  class Dummy(val ffClient: FeatureFlagClient)
+
+  @Inject
+  lateinit var dummy: Dummy
+
+  @Test
+  fun `ensure ConfigFileClient is injected when no MockBean is defined`() {
+    assertTrue { dummy.ffClient is ConfigFileClient }
+  }
+}
+
+@MicronautTest(rebuildContext = true)
+class MockBeanTest {
+  @Singleton
+  class Dummy(val ffClient: FeatureFlagClient)
+
+  @Inject
+  lateinit var dummy: Dummy
+
+  @Test
+  fun `ensure MockBean is injected when @MockBean is defined`() {
+    assertTrue { dummy.ffClient is TestClient }
+  }
+
+  @MockBean(FeatureFlagClient::class)
+  fun featureFlagClient(): TestClient = mockk<TestClient>()
+}

spotbugs-exclude-filter-file.xml

@@ -6,18 +6,21 @@
 
   <!-- examples: https://spotbugs.readthedocs.io/en/stable/filter.html#complete-example -->
   <Match>
-    <Source name="~.*build/generated.*" />
+    <Source name="~.*build/generated.*"/>
   </Match>
   <Match>
-    <Package name="io.airbyte.workers.general.jmh_generated.*" />
+    <Package name="io.airbyte.workers.general.jmh_generated.*"/>
   </Match>
   <Match>
-    <Package name="io.airbyte.api.client.*" />
+    <Package name="io.airbyte.api.client.*"/>
   </Match>
   <!-- Suppress warning about use if InputStream#readObject. The usage is safe because it is not from an untrusted source. -->
   <Match>
-    <Class name="io.airbyte.integrations.debezium.internals.AirbyteFileOffsetBackingStore" />
-    <Bug code="SECOBDES" />
+    <Class name="io.airbyte.integrations.debezium.internals.AirbyteFileOffsetBackingStore"/>
+    <Bug code="SECOBDES"/>
+  </Match>
+  <Match>
+    <Source name="~.*\.kt"/>
   </Match>
   <Match>
     <Package name="io.airbyte.server.repositories.domain.*" />