Merge branch 'fix/lmi-invocation-lifecycle' into feature/invocation-executor-isolation

Author: Frank Chen

sdk/src/main/java/software/amazon/lambda/durable/execution/ApiRequestDelayedBatcher.java

@@ -25,7 +25,7 @@
  * @param <T> Request type
  */
 public class ApiRequestDelayedBatcher<T> {
-    private static final Duration MAX_DELAY = Duration.ofMinutes(60);
+    private static final long NO_FLUSH_DEADLINE = Long.MAX_VALUE;
 
     /** Maximum items allowed in a single batch */
     private final int maxItemCount;
@@ -120,8 +120,9 @@ void shutdown(Duration timeout) throws InterruptedException, ExecutionException,
     /** clear the current batch and creates a new batch */
     private void initializeDelayedBatch() {
         this.delayedBatch.clear();
-        // MAX_DELAY is longer than a single Lambda invocation
-        this.delayedBatchFlushTime = System.nanoTime() + MAX_DELAY.toNanos();
+        // No timer is scheduled until the first item supplies an actual flush deadline. Using an unbounded sentinel
+        // avoids coupling batching behavior to the maximum Lambda invocation duration.
+        this.delayedBatchFlushTime = NO_FLUSH_DEADLINE;
 
         // the timer future is created initially without a timeout until an item is added to the batch
         this.delayedBatchFlushTimer = new CompletableFuture<>();

sdk/src/test/java/software/amazon/lambda/durable/execution/ApiRequestDelayedBatcherTest.java

@@ -212,6 +212,19 @@ void whenEarlierDelaySubmitted_batchFlushesAtEarlierTime() {
         verify(doBatchAction).accept(any());
     }
 
+    @Test
+    void whenDelayExceedsNinetyMinutes_firstSubmissionStillSetsFlushDeadline() throws Exception {
+        var submittedAt = System.nanoTime();
+        cut.submit(input, Duration.ofMinutes(91));
+
+        var flushTimeField = ApiRequestDelayedBatcher.class.getDeclaredField("delayedBatchFlushTime");
+        flushTimeField.setAccessible(true);
+        var flushTime = flushTimeField.getLong(cut);
+
+        assertTrue(flushTime > submittedAt + Duration.ofMinutes(90).toNanos());
+        cut.shutdown(SHUTDOWN_TIMEOUT);
+    }
+
     @Test
     void whenNoItemsSubmitted_shutdownDoesNotInvokeBatchAction() throws Exception {
         cut.shutdown(SHUTDOWN_TIMEOUT);