[e2e] Strip any trailing Spark error log from spark-sql output before comparison

paimon-e2e-tests/src/test/java/org/apache/paimon/tests/SparkE2eOutputTest.java

@@ -0,0 +1,73 @@
+/*
+ * 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.paimon.tests;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/** Tests for {@link SparkE2eTest#stripTrailingSparkErrorLogs(String)}. Does not need Docker. */
+public class SparkE2eOutputTest {
+
+    private static final String ROWS = "1\t10\tHi\n2\t20\tHello\n3\t30\tTable\n";
+
+    private static final String COARSE_GRAINED_SCHEDULER_ERROR =
+            "26/07/29 04:25:43 ERROR Utils: Uncaught exception in thread dispatcher-CoarseGrainedScheduler\n"
+                    + "org.apache.spark.SparkException: Could not find CoarseGrainedScheduler.\n"
+                    + "\tat org.apache.spark.rpc.netty.Dispatcher.postMessage(Dispatcher.scala:178)\n";
+
+    private static final String TRANSPORT_REQUEST_HANDLER_ERROR =
+            "26/08/30 07:28:25 ERROR TransportRequestHandler: Error while invoking RpcHandler#receive() for one-way message.\n"
+                    + "org.apache.spark.SparkException: Could not find AppClient.\n"
+                    + "\tat org.apache.spark.rpc.netty.Dispatcher.postMessage(Dispatcher.scala:178)\n"
+                    + "\tat java.lang.Thread.run(Thread.java:748)\n";
+
+    @Test
+    public void testNoErrorLogIsUnchanged() {
+        assertThat(SparkE2eTest.stripTrailingSparkErrorLogs(ROWS)).isEqualTo(ROWS);
+    }
+
+    @Test
+    public void testStripsCoarseGrainedSchedulerError() {
+        assertThat(SparkE2eTest.stripTrailingSparkErrorLogs(ROWS + COARSE_GRAINED_SCHEDULER_ERROR))
+                .isEqualTo(ROWS);
+    }
+
+    @Test
+    public void testStripsRepeatedTransportRequestHandlerErrors() {
+        assertThat(
+                        SparkE2eTest.stripTrailingSparkErrorLogs(
+                                ROWS
+                                        + TRANSPORT_REQUEST_HANDLER_ERROR
+                                        + TRANSPORT_REQUEST_HANDLER_ERROR))
+                .isEqualTo(ROWS);
+    }
+
+    @Test
+    public void testErrorOnFirstLineYieldsEmptyOutput() {
+        assertThat(SparkE2eTest.stripTrailingSparkErrorLogs(TRANSPORT_REQUEST_HANDLER_ERROR))
+                .isEmpty();
+    }
+
+    @Test
+    public void testErrorWordInsideResultRowIsKept() {
+        String rows = "1\t10\tsome ERROR text\n2\t20\tERROR Foo\n";
+        assertThat(SparkE2eTest.stripTrailingSparkErrorLogs(rows)).isEqualTo(rows);
+    }
+}

paimon-e2e-tests/src/test/java/org/apache/paimon/tests/SparkE2eTest.java

@@ -18,6 +18,8 @@
 
 package org.apache.paimon.tests;
 
+import org.apache.paimon.annotation.VisibleForTesting;
+
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.condition.DisabledOnJre;
 import org.slf4j.Logger;
@@ -27,6 +29,8 @@
 
 import java.util.Arrays;
 import java.util.UUID;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
 import static org.junit.jupiter.api.condition.JRE.JAVA_11;
@@ -36,8 +40,14 @@
 public class SparkE2eTest extends E2eReaderTestBase {
 
     private static final Logger LOG = LoggerFactory.getLogger(SparkE2eTest.class);
-    private static final String COARSE_GRAINED_SCHEDULER_SHUTDOWN_ERROR =
-            "ERROR Utils: Uncaught exception in thread dispatcher-CoarseGrainedScheduler";
+
+    /**
+     * Start of a Spark ERROR log line in the default log4j2 pattern ({@code %d{yy/MM/dd HH:mm:ss}
+     * %p %c{1}: %m%n%ex}), which spark-sql writes to stdout. Anchoring on the timestamp prefix
+     * avoids matching an "ERROR" word inside a result row.
+     */
+    private static final Pattern SPARK_ERROR_LOG_LINE =
+            Pattern.compile("(?m)^\\d{2}/\\d{2}/\\d{2} \\d{2}:\\d{2}:\\d{2} ERROR ");
 
     public SparkE2eTest() {
         super(false, false, true);
@@ -77,23 +87,25 @@ public void testFlinkWriteAndSparkRead() throws Exception {
                         LOG.info(execResult.getStderr());
                         throw new AssertionError("Failed when running spark sql.");
                     }
-                    String stdout =
-                            stripCoarseGrainedSchedulerShutdownError(execResult.getStdout());
+                    String stdout = stripTrailingSparkErrorLogs(execResult.getStdout());
                     return Arrays.stream(stdout.split("\n"))
                                     .filter(s -> !s.contains("WARN"))
                                     .collect(Collectors.joining("\n"))
                             + "\n";
                 });
     }
 
-    private static String stripCoarseGrainedSchedulerShutdownError(String stdout) {
-        int errorIndex = stdout.indexOf(COARSE_GRAINED_SCHEDULER_SHUTDOWN_ERROR);
-        if (errorIndex < 0) {
-            return stdout;
-        }
-
-        int errorLineStart = stdout.lastIndexOf('\n', errorIndex);
-        return errorLineStart < 0 ? "" : stdout.substring(0, errorLineStart);
+    /**
+     * Drops everything from the first Spark ERROR log line onwards. When spark-sql exits, the
+     * driver shutdown races with RPC dispatch and may log after the query result, with exit code 0,
+     * e.g. {@code ERROR Utils: Uncaught exception in thread dispatcher-CoarseGrainedScheduler} or
+     * {@code ERROR TransportRequestHandler: Error while invoking RpcHandler#receive() for one-way
+     * message.} followed by a stack trace.
+     */
+    @VisibleForTesting
+    static String stripTrailingSparkErrorLogs(String stdout) {
+        Matcher matcher = SPARK_ERROR_LOG_LINE.matcher(stdout);
+        return matcher.find() ? stdout.substring(0, matcher.start()) : stdout;
     }
 
     private ContainerState getSpark() {