snapshot of https://github.com/seaweedfs/seaweedfs.git (master, 2026-09-16; blobs > 131072B omitted)

test/kafka/kafka-client-loadtest/SeekToBeginningTest.java

@@ -0,0 +1,179 @@
+import org.apache.kafka.clients.consumer.*;
+import org.apache.kafka.clients.consumer.internals.*;
+import org.apache.kafka.common.TopicPartition;
+import org.apache.kafka.common.serialization.ByteArrayDeserializer;
+import org.apache.kafka.common.errors.TimeoutException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import java.util.*;
+
+/**
+ * Enhanced test program to reproduce and diagnose the seekToBeginning() hang issue
+ * 
+ * This test:
+ * 1. Adds detailed logging of Kafka client operations
+ * 2. Captures exceptions and timeouts
+ * 3. Shows what the consumer is waiting for
+ * 4. Tracks request/response lifecycle
+ */
+public class SeekToBeginningTest {
+    private static final Logger log = LoggerFactory.getLogger(SeekToBeginningTest.class);
+    
+    public static void main(String[] args) throws Exception {
+        String bootstrapServers = "localhost:9093";
+        String topicName = "_schemas";
+
+        if (args.length > 0) {
+            bootstrapServers = args[0];
+        }
+
+        Properties props = new Properties();
+        props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, bootstrapServers);
+        props.put(ConsumerConfig.GROUP_ID_CONFIG, "test-seek-group");
+        props.put(ConsumerConfig.CLIENT_ID_CONFIG, "test-seek-client");
+        props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
+        props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, "false");
+        props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, ByteArrayDeserializer.class);
+        props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, ByteArrayDeserializer.class);
+        props.put(ConsumerConfig.SESSION_TIMEOUT_MS_CONFIG, "45000");
+        props.put(ConsumerConfig.REQUEST_TIMEOUT_MS_CONFIG, "60000");
+        
+        // Add comprehensive debug logging
+        props.put("log4j.logger.org.apache.kafka.clients.consumer.internals", "DEBUG");
+        props.put("log4j.logger.org.apache.kafka.clients.producer.internals", "DEBUG");
+        props.put("log4j.logger.org.apache.kafka.clients.Metadata", "DEBUG");
+        
+        // Add shorter timeouts to fail faster
+        props.put(ConsumerConfig.DEFAULT_API_TIMEOUT_MS_CONFIG, "10000"); // 10 seconds instead of 60
+        
+        System.out.println("\n╔════════════════════════════════════════════════════════════╗");
+        System.out.println("║         SeekToBeginning Diagnostic Test                      ║");
+        System.out.println(String.format("║     Connecting to: %-42s║", bootstrapServers));
+        System.out.println("╚════════════════════════════════════════════════════════════╝\n");
+
+        System.out.println("[TEST] Creating KafkaConsumer...");
+        System.out.println("[TEST] Bootstrap servers: " + bootstrapServers);
+        System.out.println("[TEST] Group ID: test-seek-group");
+        System.out.println("[TEST] Client ID: test-seek-client");
+        
+        KafkaConsumer<byte[], byte[]> consumer = new KafkaConsumer<>(props);
+
+        TopicPartition tp = new TopicPartition(topicName, 0);
+        List<TopicPartition> partitions = Arrays.asList(tp);
+
+        System.out.println("\n[STEP 1] Assigning to partition: " + tp);
+        consumer.assign(partitions);
+        System.out.println("[STEP 1] ✓ Assigned successfully");
+
+        System.out.println("\n[STEP 2] Calling seekToBeginning()...");
+        long startTime = System.currentTimeMillis();
+        try {
+            consumer.seekToBeginning(partitions);
+            long seekTime = System.currentTimeMillis() - startTime;
+            System.out.println("[STEP 2] ✓ seekToBeginning() completed in " + seekTime + "ms");
+        } catch (Exception e) {
+            System.out.println("[STEP 2] ✗ EXCEPTION in seekToBeginning():");
+            e.printStackTrace();
+            consumer.close();
+            return;
+        }
+
+        System.out.println("\n[STEP 3] Starting poll loop...");
+        System.out.println("[STEP 3] First poll will trigger offset lookup (ListOffsets)");
+        System.out.println("[STEP 3] Then will fetch initial records\n");
+        
+        int successfulPolls = 0;
+        int failedPolls = 0;
+        int totalRecords = 0;
+
+        for (int i = 0; i < 3; i++) {
+            System.out.println("═══════════════════════════════════════════════════════════");
+            System.out.println("[POLL " + (i + 1) + "] Starting poll with 15-second timeout...");
+            long pollStart = System.currentTimeMillis();
+            
+            try {
+                System.out.println("[POLL " + (i + 1) + "] Calling consumer.poll()...");
+                ConsumerRecords<byte[], byte[]> records = consumer.poll(java.time.Duration.ofSeconds(15));
+                long pollTime = System.currentTimeMillis() - pollStart;
+                
+                System.out.println("[POLL " + (i + 1) + "] ✓ Poll completed in " + pollTime + "ms");
+                System.out.println("[POLL " + (i + 1) + "] Records received: " + records.count());
+                
+                if (records.count() > 0) {
+                    successfulPolls++;
+                    totalRecords += records.count();
+                    for (ConsumerRecord<byte[], byte[]> record : records) {
+                        System.out.println("  [RECORD] offset=" + record.offset() + 
+                                         ", key.len=" + (record.key() != null ? record.key().length : 0) +
+                                         ", value.len=" + (record.value() != null ? record.value().length : 0));
+                    }
+                } else {
+                    System.out.println("[POLL " + (i + 1) + "] ℹ No records in this poll (but no error)");
+                    successfulPolls++;
+                }
+            } catch (TimeoutException e) {
+                long pollTime = System.currentTimeMillis() - pollStart;
+                failedPolls++;
+                System.out.println("[POLL " + (i + 1) + "] ✗ TIMEOUT after " + pollTime + "ms");
+                System.out.println("[POLL " + (i + 1) + "] This means consumer is waiting for something from broker");
+                System.out.println("[POLL " + (i + 1) + "] Possible causes:");
+                System.out.println("         - ListOffsetsRequest never sent");
+                System.out.println("         - ListOffsetsResponse not received");
+                System.out.println("         - Broker metadata parsing failed");
+                System.out.println("         - Connection issue");
+                
+                // Print current position info if available
+                try {
+                    long position = consumer.position(tp);
+                    System.out.println("[POLL " + (i + 1) + "] Current position: " + position);
+                } catch (Exception e2) {
+                    System.out.println("[POLL " + (i + 1) + "] Could not get position: " + e2.getMessage());
+                }
+            } catch (Exception e) {
+                failedPolls++;
+                long pollTime = System.currentTimeMillis() - pollStart;
+                System.out.println("[POLL " + (i + 1) + "] ✗ EXCEPTION after " + pollTime + "ms:");
+                System.out.println("[POLL " + (i + 1) + "] Exception type: " + e.getClass().getSimpleName());
+                System.out.println("[POLL " + (i + 1) + "] Message: " + e.getMessage());
+                
+                // Print stack trace for first exception
+                if (i == 0) {
+                    System.out.println("[POLL " + (i + 1) + "] Stack trace:");
+                    e.printStackTrace();
+                }
+            }
+        }
+
+        System.out.println("\n═══════════════════════════════════════════════════════════");
+        System.out.println("[RESULTS] Test Summary:");
+        System.out.println("  Successful polls: " + successfulPolls);
+        System.out.println("  Failed polls: " + failedPolls);
+        System.out.println("  Total records received: " + totalRecords);
+        
+        if (failedPolls > 0) {
+            System.out.println("\n[DIAGNOSIS] Consumer is BLOCKED during poll()");
+            System.out.println("  This indicates the consumer cannot:");
+            System.out.println("  1. Send ListOffsetsRequest to determine offset 0, OR");
+            System.out.println("  2. Receive/parse ListOffsetsResponse from broker, OR");
+            System.out.println("  3. Parse broker metadata for partition leader lookup");
+        } else if (totalRecords == 0) {
+            System.out.println("\n[DIAGNOSIS] Consumer is working but NO records found");
+            System.out.println("  This might mean:");
+            System.out.println("  1. Topic has no messages, OR");
+            System.out.println("  2. Fetch is working but broker returns empty");
+        } else {
+            System.out.println("\n[SUCCESS] Consumer working correctly!");
+            System.out.println("  Received " + totalRecords + " records");
+        }
+
+        System.out.println("\n[CLEANUP] Closing consumer...");
+        try {
+            consumer.close();
+            System.out.println("[CLEANUP] ✓ Consumer closed successfully");
+        } catch (Exception e) {
+            System.out.println("[CLEANUP] ✗ Error closing consumer: " + e.getMessage());
+        }
+        
+        System.out.println("\n[TEST] Done!\n");
+    }
+}