[FLINK-35094] SinkTestSuiteBase.testScaleDown is hanging for 1.20-SNA…

…PSHOT

flink-connector-elasticsearch-e2e-tests/flink-connector-elasticsearch-e2e-tests-common/src/main/java/org/apache/flink/core/execution/CheckpointingMode.java

@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.core.execution;
+
+/**
+ * This is a copy of {@link CheckpointingMode} from flink-core module introduced in Flink 1.20. We
+ * need it here to make E2E Sink tests compatible with earlier releases. Could be removed together
+ * with dropping support of Flink 1.19.
+ */
+public enum CheckpointingMode {
+    EXACTLY_ONCE,
+    AT_LEAST_ONCE;
+
+    private CheckpointingMode() {}
+}

flink-connector-elasticsearch-e2e-tests/flink-connector-elasticsearch-e2e-tests-common/src/main/java/org/apache/flink/streaming/tests/ElasticsearchSinkE2ECaseBase.java

@@ -38,6 +38,7 @@
 import java.util.stream.Collectors;
 
 import static org.apache.flink.connector.testframe.utils.CollectIteratorAssertions.assertThat;
+import static org.apache.flink.core.execution.CheckpointingMode.convertFromCheckpointingMode;
 import static org.apache.flink.runtime.testutils.CommonTestUtils.waitUntilCondition;
 
 /** Base classs for end to end ElasticsearchSink tests based on connector testing framework. */
@@ -72,7 +73,8 @@ public abstract class ElasticsearchSinkE2ECaseBase<T extends Comparable<T>>
                     .bindWithFlinkContainer(flink.getFlinkContainers().getJobManager())
                     .build();
 
-    @Override
+    /** Could be removed together with dropping support of Flink 1.19. */
+    @Deprecated
     protected void checkResultWithSemantic(
             ExternalSystemDataReader<T> reader, List<T> testData, CheckpointingMode semantic)
             throws Exception {
@@ -93,9 +95,46 @@ protected void checkResultWithSemantic(
                 READER_RETRY_ATTEMPTS);
     }
 
+    protected void checkResultWithSemantic(
+            ExternalSystemDataReader<T> reader,
+            List<T> testData,
+            org.apache.flink.core.execution.CheckpointingMode semantic)
+            throws Exception {
+        waitUntilCondition(
+                () -> {
+                    try {
+                        List<T> result = reader.poll(Duration.ofMillis(READER_TIMEOUT));
+                        assertThat(sort(result).iterator())
+                                .matchesRecordsFromSource(
+                                        Collections.singletonList(sort(testData)),
+                                        convertFromCheckpointingMode(semantic));
+                        return true;
+                    } catch (Throwable t) {
+                        LOG.warn("Polled results not as expected", t);
+                        return false;
+                    }
+                },
+                5000,
+                READER_RETRY_ATTEMPTS);
+    }
+
     private List<T> sort(List<T> list) {
         return list.stream().sorted().collect(Collectors.toList());
     }
 
+    /** Could be removed together with dropping support of Flink 1.19. */
+    @Deprecated
+    private static org.apache.flink.streaming.api.CheckpointingMode convertFromCheckpointingMode(
+            org.apache.flink.core.execution.CheckpointingMode semantic) {
+        switch (semantic) {
+            case EXACTLY_ONCE:
+                return org.apache.flink.streaming.api.CheckpointingMode.EXACTLY_ONCE;
+            case AT_LEAST_ONCE:
+                return org.apache.flink.streaming.api.CheckpointingMode.AT_LEAST_ONCE;
+            default:
+                throw new IllegalArgumentException("Unsupported semantic: " + semantic);
+        }
+    }
+
     abstract String getElasticsearchContainerName();
 }