fix(contribution): use unique consumer group id for each phase

Previous consumer group had already consumed messages, so fromBeginning
had no effect. Now using timestamp-based unique group id to ensure
fresh consumption from beginning each time.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/services/contribution-service/src/infrastructure/kafka/cdc-consumer.service.ts

@@ -333,9 +333,33 @@ export class CDCConsumerService implements OnModuleInit, OnModuleDestroy {
    * 消费单个阶段直到追上最新消息
    */
   private async consumePhaseToEnd(phase: TopicPhase): Promise<void> {
-    // 创建临时 consumer 用于单个 topic
+    const admin = this.kafka.admin();
+    await admin.connect();
+
+    // 获取 topic 的高水位线和最早 offset
+    const topicOffsets = await admin.fetchTopicOffsets(phase.topic);
+    const highWatermarks: Map<number, string> = new Map();
+    const earliestOffsets: Map<number, string> = new Map();
+
+    for (const partitionOffset of topicOffsets) {
+      highWatermarks.set(partitionOffset.partition, partitionOffset.high);
+      earliestOffsets.set(partitionOffset.partition, partitionOffset.low);
+    }
+
+    this.logger.log(`[CDC] Phase ${phase.tableName}: High watermarks = ${JSON.stringify(Object.fromEntries(highWatermarks))}`);
+
+    // 检查是否 topic 为空
+    const allEmpty = Array.from(highWatermarks.values()).every(hw => hw === '0');
+    if (allEmpty) {
+      this.logger.log(`[CDC] Phase ${phase.tableName}: Topic is empty, skipping`);
+      await admin.disconnect();
+      return;
+    }
+
+    // 使用唯一的 group id（每次启动都重新消费）
+    const uniqueGroupId = `contribution-service-cdc-phase-${phase.tableName}-${Date.now()}`;
     const phaseConsumer = this.kafka.consumer({
-      groupId: `contribution-service-cdc-phase-${phase.tableName}`,
+      groupId: uniqueGroupId,
     });
 
     try {
@@ -347,30 +371,11 @@ export class CDCConsumerService implements OnModuleInit, OnModuleDestroy {
         fromBeginning: true,
       });
 
-      // 获取 topic 的高水位线（最新 offset）
-      const admin = this.kafka.admin();
-      await admin.connect();
-
-      let highWatermarks: Map<number, string> = new Map();
       let processedOffsets: Map<number, bigint> = new Map();
       let isComplete = false;
 
-      // 获取 topic 的 partition 信息和高水位线
+      for (const partition of highWatermarks.keys()) {
-      const topicOffsets = await admin.fetchTopicOffsets(phase.topic);
+        processedOffsets.set(partition, BigInt(-1));
-      for (const partitionOffset of topicOffsets) {
-        highWatermarks.set(partitionOffset.partition, partitionOffset.high);
-        processedOffsets.set(partitionOffset.partition, BigInt(-1));
-      }
-      await admin.disconnect();
-
-      this.logger.log(`[CDC] Phase ${phase.tableName}: High watermarks = ${JSON.stringify(Object.fromEntries(highWatermarks))}`);
-
-      // 检查是否 topic 为空
-      const allEmpty = Array.from(highWatermarks.values()).every(hw => hw === '0');
-      if (allEmpty) {
-        this.logger.log(`[CDC] Phase ${phase.tableName}: Topic is empty, skipping`);
-        await phaseConsumer.disconnect();
-        return;
       }
 
       // 开始消费
@@ -403,7 +408,7 @@ export class CDCConsumerService implements OnModuleInit, OnModuleDestroy {
       while (!isComplete) {
         await new Promise(resolve => setTimeout(resolve, 100));
 
-        // 超时保护：每5秒检查一次进度
+        // 每秒检查一次进度
         const currentProgress = Array.from(processedOffsets.entries())
           .map(([p, o]) => `P${p}:${o}/${highWatermarks.get(p)}`)
           .join(', ');
@@ -414,9 +419,18 @@ export class CDCConsumerService implements OnModuleInit, OnModuleDestroy {
       await phaseConsumer.stop();
       await phaseConsumer.disconnect();
 
+      // 删除临时 consumer group
+      try {
+        await admin.deleteGroups([uniqueGroupId]);
+      } catch {
+        // 忽略删除失败
+      }
+      await admin.disconnect();
+
     } catch (error) {
       this.logger.error(`[CDC] Error in phase ${phase.tableName}`, error);
       await phaseConsumer.disconnect();
+      await admin.disconnect();
       throw error;
     }
   }