chore: cut the comment density in the async pool changeset

Author: JanCizmar

backend/api/src/main/kotlin/io/tolgee/websocket/ActivityWebsocketListener.kt

@@ -32,8 +32,7 @@ class ActivityWebsocketListener(
   private val relationDescriptionExtractor: RelationDescriptionExtractor,
   private val currentDateProvider: CurrentDateProvider,
 ) {
-  // Not the default pool: this one is single-threaded, and the webapp applies these events as
-  // ordered deltas.
+  // Ordering-sensitive — keep the qualifier; see websocketAsyncExecutor for why.
   @Async("websocketAsyncExecutor")
   @EventListener
   fun onActivity(event: OnProjectActivityStoredEvent) {

backend/app/src/main/kotlin/io/tolgee/configuration/AsyncExecutorFactory.kt

@@ -15,12 +15,7 @@ class AsyncExecutorFactory(
   private val tolgeeProperties: TolgeeProperties,
   private val dataSourceProvider: ObjectProvider<DataSource>,
 ) {
-  /**
-   * Null when the DataSource is not a HikariDataSource, which is the only thing that can report a
-   * pool size. Read from the live bean rather than from `spring.datasource.*`, because
-   * PostgresAutoStartConfiguration binds those properties straight onto the HikariDataSource and so
-   * which key wins depends on whether autostart is enabled.
-   */
+  /** Read off the live bean, not `spring.datasource.*` — see PostgresAutoStartConfiguration. */
   val connectionPoolSize: Int? by lazy {
     (dataSourceProvider.ifAvailable as? HikariDataSource)?.maximumPoolSize
   }
@@ -78,7 +73,6 @@ class AsyncExecutorFactory(
     const val BACKGROUND_POOL_DIVISOR = 6
     const val FALLBACK_CONNECTION_POOL_SIZE = 10
 
-    /** Matches the pre-existing @Async behaviour: background work is queued, never rejected. */
     const val UNBOUNDED_QUEUE = Int.MAX_VALUE
 
     const val STREAMING_THREAD_NAME_PREFIX = "tolgee-stream-"

backend/app/src/main/kotlin/io/tolgee/configuration/AsyncMethodConfiguration.kt

@@ -19,7 +19,6 @@ class AsyncMethodConfiguration(
 ) : AsyncConfigurer {
   override fun getAsyncExecutor(): Executor = backgroundAsyncExecutor()
 
-  // @Primary so the two special-purpose pools below cannot win a by-type TaskExecutor injection.
   @Primary
   @Bean(BACKGROUND_EXECUTOR_BEAN_NAME)
   fun backgroundAsyncExecutor(): ThreadPoolTaskExecutor {

backend/app/src/test/kotlin/io/tolgee/ExceptionHandlersAsyncCapacityTest.kt

@@ -29,10 +29,6 @@ class ExceptionHandlersAsyncCapacityTest {
       .isEqualTo(Message.SERVER_BUSY.code)
   }
 
-  /**
-   * The streaming return-value handler stages these before the task is submitted; a caching proxy
-   * would otherwise key the 503 against that ETag.
-   */
   @Test
   fun `drops the streaming headers already staged on the response`() {
     val response = MockHttpServletResponse()
@@ -46,7 +42,6 @@ class ExceptionHandlersAsyncCapacityTest {
     response.getHeader(HttpHeaders.ETAG).assert.isNull()
   }
 
-  /** Without these the browser reports a CORS failure instead of surfacing the 503. */
   @Test
   fun `keeps the CORS and version headers written by earlier filters`() {
     val response = MockHttpServletResponse()
@@ -75,7 +70,6 @@ class ExceptionHandlersAsyncCapacityTest {
     response.getHeader(HttpHeaders.CONTENT_DISPOSITION).assert.isNotNull
   }
 
-  /** Any other executor's rejection is not ours to relabel as streaming saturation. */
   @Test
   fun `sends a rejection from another executor down the generic path`() {
     val unrelated = TaskRejectedException("some other executor is shutting down")
@@ -102,7 +96,6 @@ class ExceptionHandlersAsyncCapacityTest {
     response.getHeader(HttpHeaders.CONTENT_DISPOSITION).assert.isNull()
   }
 
-  /** A stream that timed out mid-write cannot be answered, and is worth reporting rather than hiding. */
   @Test
   fun `reports a stream that timed out after it started writing`() {
     val response = MockHttpServletResponse()
@@ -116,7 +109,6 @@ class ExceptionHandlersAsyncCapacityTest {
   private fun handle(response: MockHttpServletResponse) =
     exceptionHandlers.handleAsyncCapacityExceeded(wrappedRejection(), response)
 
-  /** Spring wraps whatever the rejection policy throws, so the handler only ever sees the wrapper. */
   private fun wrappedRejection(): RejectedExecutionException =
     TaskRejectedException("pool full", StreamingCapacityExceededException("queued=1, active=1"))
 }

backend/app/src/test/kotlin/io/tolgee/StreamingBodyDatabasePoolHealthTest.kt

@@ -61,8 +61,6 @@ class StreamingBodyDatabasePoolHealthTest : ProjectAuthControllerTest("/v2/proje
     val hikariDataSource = dataSource as HikariDataSource
     val pool = hikariDataSource.hikariPoolMXBean
 
-    // Every streaming response borrows a connection for its whole duration, so a stream that
-    // fails to hand it back leaves it active forever.
     waitForNotThrowing(pollTime = 50, timeout = 5000) {
       pool.activeConnections.assert.isEqualTo(0)
     }

backend/app/src/test/kotlin/io/tolgee/configuration/AsyncCapacityReporterTest.kt

@@ -13,7 +13,6 @@ import org.slf4j.LoggerFactory
 class AsyncCapacityReporterTest {
   @Test
   fun `stays quiet when a quarter of the connection pool is left for ordinary requests`() {
-    // 33 streaming + 16 background + 20 batch = 69 of 100, leaving 31.
     val events = report(connectionPoolSize = 100, batchConcurrency = 20)
 
     events.warnings.assert.isEmpty()
@@ -22,16 +21,11 @@ class AsyncCapacityReporterTest {
 
   @Test
   fun `warns when the pools plus batch jobs crowd out ordinary requests`() {
-    // 33 streaming + 16 background + 40 batch = 89 of 100.
     val events = report(connectionPoolSize = 100, batchConcurrency = 40)
 
     events.warnings.assert.anyMatch { it.contains("may starve the database connection pool") }
   }
 
-  /**
-   * Which key actually sets the pool size flips with postgres-autostart, so naming the wrong one
-   * would send an operator to a property their deployment silently ignores.
-   */
   @Test
   fun `names the connection pool property that the active binding mode actually reads`() {
     report(connectionPoolSize = 100, batchConcurrency = 40, postgresAutostart = true)
@@ -45,8 +39,6 @@ class AsyncCapacityReporterTest {
 
   @Test
   fun `sits exactly on the boundary without warning, and warns one job past it`() {
-    // pool 60 -> 20 streaming + 10 background, and the reserve is 60/4 = 15, so 15 batch jobs is
-    // the last configuration that still leaves a quarter free.
     report(connectionPoolSize = 60, batchConcurrency = 15).warnings.assert.isEmpty()
     report(connectionPoolSize = 60, batchConcurrency = 16).warnings.assert.isNotEmpty()
   }

backend/app/src/test/kotlin/io/tolgee/configuration/AsyncDispatchTargetTest.kt

@@ -11,11 +11,6 @@ import org.springframework.scheduling.annotation.Async
 import java.util.concurrent.CompletableFuture
 import java.util.concurrent.TimeUnit
 
-/**
- * The MVC side has a wiring test; without this the @Async side could silently fall back to Spring's
- * own executor, or the websocket qualifier could resolve to the general pool, and every
- * configuration assertion would still pass.
- */
 @SpringBootTest
 @Import(AsyncDispatchTargetTest.AsyncProbeConfiguration::class)
 class AsyncDispatchTargetTest {

backend/app/src/test/kotlin/io/tolgee/configuration/AsyncExecutorConfigurationTest.kt

@@ -51,10 +51,6 @@ class AsyncExecutorConfigurationTest {
   @Autowired
   private lateinit var asyncMethodConfiguration: AsyncMethodConfiguration
 
-  /**
-   * Hard-coded rather than recomputed from the divisors, so a change to either divisor has to be
-   * made here too instead of silently agreeing with itself.
-   */
   @Test
   fun `derives both pools from the database connection pool`() {
     (dataSource as HikariDataSource)
@@ -68,10 +64,6 @@ class AsyncExecutorConfigurationTest {
     asyncExecutorFactory.backgroundMaxThreads.assert.isEqualTo(16)
   }
 
-  /**
-   * Guards against silently falling back to ThreadPoolTaskExecutor's defaults, which pin a pool to a
-   * single thread forever because the unbounded queue never lets it grow past core size.
-   */
   @Test
   fun `no pool is left at the single-threaded default`() {
     listOf(streamingAsyncExecutor, asyncMethodConfiguration.backgroundAsyncExecutor()).forEach { executor ->
@@ -131,10 +123,6 @@ class AsyncExecutorConfigurationTest {
       .isEqualTo(AsyncMethodConfiguration.WEBSOCKET_EXECUTOR_BEAN_NAME)
   }
 
-  /**
-   * Without this, dropping the configureAsyncSupport override would silently fall back to Spring's
-   * own executor and every other test here would still pass.
-   */
   @Test
   fun `mvc async dispatch runs on the streaming executor`() {
     val installed = ReflectionTestUtils.getField(requestMappingHandlerAdapter, "taskExecutor")
@@ -144,10 +132,6 @@ class AsyncExecutorConfigurationTest {
     delegate.assert.isSameAs(streamingAsyncExecutor)
   }
 
-  /**
-   * StreamingBodyDatabasePoolHealthTest was de-flaked on this setting, but it would go back to
-   * skipping rather than failing if the setting were lost. This fails outright.
-   */
   @Test
   fun `security headers are written before the chain, not while it unwinds`() {
     val headerWriterFilter =
@@ -167,7 +151,6 @@ class AsyncExecutorConfigurationTest {
       .isInstanceOf(CompositeTaskDecorator::class.java)
   }
 
-  /** The two divisors and the reporter's reserve are separate constants; defaults must agree. */
   @Test
   fun `the shipped defaults never trip the capacity warning`() {
     val poolSize = asyncExecutorFactory.connectionPoolSize!!
@@ -209,7 +192,6 @@ class AsyncExecutorConfigurationTest {
         ).apply { initialize() }
     val release = CyclicBarrier(2)
     try {
-      // Occupies the single thread, then fills the single queue slot.
       executor.submit { release.await(10, TimeUnit.SECONDS) }
       executor.submit { }
 

backend/app/src/test/kotlin/io/tolgee/configuration/AsyncPoolSizeDerivationTest.kt

@@ -6,10 +6,6 @@ import io.tolgee.testing.assert
 import org.junit.jupiter.api.Test
 import javax.sql.DataSource
 
-/**
- * Plain unit test so the floor and the "not a Hikari pool" fallback are reachable — a @SpringBootTest
- * is stuck with whatever connection pool the test context happens to have.
- */
 class AsyncPoolSizeDerivationTest {
   @Test
   fun `derives each pool by its divisor`() {

backend/app/src/test/kotlin/io/tolgee/configuration/AsyncPropertyBindingTest.kt

@@ -7,10 +7,6 @@ import org.springframework.beans.factory.annotation.Qualifier
 import org.springframework.boot.test.context.SpringBootTest
 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor
 
-/**
- * The deployment values.yaml pins tolgee.async.* explicitly, so those keys have to survive relaxed
- * binding all the way into the executors — nothing else in the suite would notice a rename.
- */
 @SpringBootTest(
   properties = [
     "tolgee.async.streaming.max-threads = 7",