feat(snapshot): 新增 MPC PostgreSQL 备份目标

MPC 系统使用独立的 PostgreSQL 实例 (mpc-postgres)，之前不在备份范围内。
新增 MPC_POSTGRES handler，通过 MPC_PG_* 环境变量连接，snapshot-service
加入 mpc-network 实现跨 compose 网络访问。

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/services/docker-compose.snapshot.yml

@@ -15,11 +15,16 @@ services:
       - NODE_ENV=production
       - APP_PORT=3099
       - DATABASE_URL=file:/app/data/snapshot.db
-      # PostgreSQL (备份目标)
+      # PostgreSQL (备份目标 - 主业务库)
       - PG_HOST=postgres
       - PG_PORT=5432
       - PG_USER=${POSTGRES_USER:-rwa_user}
       - PG_PASSWORD=${POSTGRES_PASSWORD}
+      # MPC PostgreSQL (备份目标 - MPC 独立库)
+      - MPC_PG_HOST=mpc-postgres
+      - MPC_PG_PORT=5432
+      - MPC_PG_USER=${MPC_POSTGRES_USER:-mpc_user}
+      - MPC_PG_PASSWORD=${MPC_POSTGRES_PASSWORD}
       # Redis (备份目标)
       - REDIS_HOST=redis
       - REDIS_PORT=6379
@@ -34,7 +39,7 @@ services:
       # 备份配置
       - SNAPSHOT_TEMP_DIR=/tmp/snapshots
       - SNAPSHOT_RETENTION_HOURS=72
-      - AVAILABLE_TARGETS=POSTGRES,REDIS,KAFKA,ZOOKEEPER,MINIO,UPLOADS
+      - AVAILABLE_TARGETS=POSTGRES,MPC_POSTGRES,REDIS,KAFKA,ZOOKEEPER,MINIO,UPLOADS
     volumes:
       - snapshot_data:/app/data
       - /tmp/rwa-snapshots:/tmp/snapshots
@@ -56,6 +61,12 @@ services:
       start_period: 30s
     networks:
       - rwa-network
+      - mpc-network
 
 volumes:
   snapshot_data:
+
+networks:
+  mpc-network:
+    external: true
+    name: mpc-system_mpc-network

backend/services/snapshot-service/.env.development

@@ -3,12 +3,18 @@ APP_PORT=3099
 DATABASE_URL="file:./data/snapshot.db"
 # Docker 部署时 docker-compose 覆盖为绝对路径: file:/app/data/snapshot.db
 
-# PostgreSQL (被备份目标)
+# PostgreSQL (被备份目标 - 主业务库)
 PG_HOST=localhost
 PG_PORT=5432
 PG_USER=rwa_user
 PG_PASSWORD=your_password
 
+# MPC PostgreSQL (被备份目标 - MPC 独立库)
+MPC_PG_HOST=localhost
+MPC_PG_PORT=5433
+MPC_PG_USER=mpc_user
+MPC_PG_PASSWORD=your_mpc_password
+
 # Redis (被备份目标)
 REDIS_HOST=localhost
 REDIS_PORT=6379
@@ -28,4 +34,4 @@ SNAPSHOT_TEMP_DIR=./data/snapshots
 SNAPSHOT_RETENTION_HOURS=72
 
 # 可用备份目标（逗号分隔，部署时按系统配置）
-AVAILABLE_TARGETS=POSTGRES,REDIS,KAFKA,ZOOKEEPER,MINIO,UPLOADS
+AVAILABLE_TARGETS=POSTGRES,MPC_POSTGRES,REDIS,KAFKA,ZOOKEEPER,MINIO,UPLOADS

backend/services/snapshot-service/src/domain/enums/backup-target.enum.ts

@@ -1,5 +1,6 @@
 export enum BackupTarget {
   POSTGRES = 'POSTGRES',
+  MPC_POSTGRES = 'MPC_POSTGRES',
   REDIS = 'REDIS',
   KAFKA = 'KAFKA',
   ZOOKEEPER = 'ZOOKEEPER',
@@ -10,6 +11,7 @@ export enum BackupTarget {
 /** 备份执行顺序 */
 export const BACKUP_TARGET_ORDER: BackupTarget[] = [
   BackupTarget.POSTGRES,
+  BackupTarget.MPC_POSTGRES,
   BackupTarget.REDIS,
   BackupTarget.KAFKA,
   BackupTarget.ZOOKEEPER,
@@ -20,6 +22,7 @@ export const BACKUP_TARGET_ORDER: BackupTarget[] = [
 /** 备份目标中文名 */
 export const BACKUP_TARGET_LABELS: Record<BackupTarget, string> = {
   [BackupTarget.POSTGRES]: 'PostgreSQL',
+  [BackupTarget.MPC_POSTGRES]: 'MPC PostgreSQL',
   [BackupTarget.REDIS]: 'Redis',
   [BackupTarget.KAFKA]: 'Kafka',
   [BackupTarget.ZOOKEEPER]: 'ZooKeeper',

backend/services/snapshot-service/src/infrastructure/backup/mpc-postgres-backup.handler.ts

@@ -0,0 +1,146 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { spawn } from 'child_process';
+import * as fs from 'fs';
+import * as path from 'path';
+import { BackupTarget } from '@/domain/enums';
+import {
+  BackupHandler,
+  BackupResult,
+  ProgressCallback,
+} from '@/domain/interfaces/backup-handler.interface';
+
+@Injectable()
+export class MpcPostgresBackupHandler implements BackupHandler {
+  readonly target = BackupTarget.MPC_POSTGRES;
+  private readonly logger = new Logger(MpcPostgresBackupHandler.name);
+
+  private readonly host: string;
+  private readonly port: string;
+  private readonly user: string;
+  private readonly password: string;
+
+  constructor(private readonly configService: ConfigService) {
+    this.host = this.configService.get<string>('MPC_PG_HOST', 'localhost');
+    this.port = this.configService.get<string>('MPC_PG_PORT', '5432');
+    this.user = this.configService.get<string>('MPC_PG_USER', 'mpc_user');
+    this.password = this.configService.get<string>('MPC_PG_PASSWORD', '');
+  }
+
+  /** 查询 MPC PostgreSQL 所有非模板数据库的总大小（字节） */
+  private getTotalDatabaseSize(): Promise<number> {
+    return new Promise((resolve) => {
+      const psql = spawn('psql', [
+        '-h', this.host,
+        '-p', this.port,
+        '-U', this.user,
+        '-t', '-A',
+        '-c', 'SELECT COALESCE(sum(pg_database_size(datname)), 0) FROM pg_database WHERE datistemplate = false',
+      ], {
+        env: { ...process.env, PGPASSWORD: this.password },
+      });
+
+      let output = '';
+      psql.stdout.on('data', (data: Buffer) => { output += data.toString(); });
+      psql.on('close', (code) => {
+        const size = parseInt(output.trim(), 10);
+        if (code === 0 && !isNaN(size) && size > 0) {
+          this.logger.log(`MPC PostgreSQL 总数据库大小: ${(size / 1024 / 1024).toFixed(1)} MB`);
+          resolve(size);
+        } else {
+          this.logger.warn(`无法获取 MPC 数据库大小 (exit=${code}), 使用默认估算 500MB`);
+          resolve(500 * 1024 * 1024);
+        }
+      });
+      psql.on('error', () => {
+        this.logger.warn('psql 不可用, 使用默认估算 500MB');
+        resolve(500 * 1024 * 1024);
+      });
+    });
+  }
+
+  async execute(outputDir: string, onProgress: ProgressCallback): Promise<BackupResult> {
+    const timestamp = new Date().toISOString().replace(/[:.]/g, '-');
+    const fileName = `mpc-postgres-${timestamp}.sql.gz`;
+    const filePath = path.join(outputDir, fileName);
+
+    fs.mkdirSync(outputDir, { recursive: true });
+
+    onProgress(0, 'MPC PostgreSQL 查询数据库大小...');
+    const totalSize = await this.getTotalDatabaseSize();
+
+    onProgress(0, 'MPC pg_dumpall 开始...');
+
+    return new Promise<BackupResult>((resolve, reject) => {
+      const dumpProc = spawn('pg_dumpall', [
+        '-h', this.host,
+        '-p', this.port,
+        '-U', this.user,
+        '--clean',
+        '--if-exists',
+      ], {
+        env: { ...process.env, PGPASSWORD: this.password },
+      });
+
+      const gzipProc = spawn('gzip', ['-6']);
+      const outputStream = fs.createWriteStream(filePath);
+
+      let bytesRead = 0;
+      let lastReportedMB = 0;
+
+      dumpProc.stdout.on('data', (chunk: Buffer) => {
+        bytesRead += chunk.length;
+        const readMB = Math.floor(bytesRead / (1024 * 1024));
+        if (readMB > lastReportedMB) {
+          lastReportedMB = readMB;
+          const totalMB = Math.floor(totalSize / (1024 * 1024));
+          const percent = Math.min(99, parseFloat(((bytesRead / totalSize) * 100).toFixed(2)));
+          onProgress(percent, `MPC PostgreSQL 备份中... ${readMB}MB / ~${totalMB}MB`);
+        }
+      });
+
+      // pipe: pg_dumpall stdout → gzip stdin → file
+      dumpProc.stdout.pipe(gzipProc.stdin);
+      gzipProc.stdout.pipe(outputStream);
+
+      let stderrBuffer = '';
+      dumpProc.stderr.on('data', (data: Buffer) => {
+        stderrBuffer += data.toString();
+      });
+
+      let dumpExitCode: number | null = null;
+      let gzipExitCode: number | null = null;
+
+      const checkDone = () => {
+        if (dumpExitCode === null || gzipExitCode === null) return;
+
+        if (dumpExitCode === 0 && gzipExitCode === 0) {
+          const stat = fs.statSync(filePath);
+          this.logger.log(`MPC PostgreSQL 备份完成: ${fileName}, 压缩后: ${stat.size} bytes, 原始输出: ${bytesRead} bytes`);
+          onProgress(100, 'MPC PostgreSQL 备份完成');
+          resolve({ fileName, filePath, fileSize: stat.size });
+        } else {
+          const error = `MPC pg_dumpall 退出码: ${dumpExitCode}, gzip 退出码: ${gzipExitCode}, stderr: ${stderrBuffer.slice(-500)}`;
+          this.logger.error(error);
+          if (fs.existsSync(filePath)) fs.unlinkSync(filePath);
+          reject(new Error(error));
+        }
+      };
+
+      dumpProc.on('close', (code) => { dumpExitCode = code; checkDone(); });
+      gzipProc.on('close', (code) => { gzipExitCode = code; checkDone(); });
+
+      dumpProc.on('error', (err) => {
+        this.logger.error(`MPC pg_dumpall 启动失败: ${err.message}`);
+        if (fs.existsSync(filePath)) fs.unlinkSync(filePath);
+        reject(new Error(`MPC pg_dumpall 启动失败: ${err.message}`));
+      });
+
+      gzipProc.on('error', (err) => {
+        this.logger.error(`gzip 启动失败: ${err.message}`);
+        if (fs.existsSync(filePath)) fs.unlinkSync(filePath);
+        reject(new Error(`gzip 启动失败: ${err.message}`));
+      });
+    });
+  }
+}

backend/services/snapshot-service/src/infrastructure/infrastructure.module.ts

@@ -3,6 +3,7 @@ import { ConfigService } from '@nestjs/config';
 import { PrismaService } from './persistence/prisma/prisma.service';
 import { SnapshotRepository } from './persistence/repositories/snapshot.repository';
 import { PostgresBackupHandler } from './backup/postgres-backup.handler';
+import { MpcPostgresBackupHandler } from './backup/mpc-postgres-backup.handler';
 import { RedisBackupHandler } from './backup/redis-backup.handler';
 import { KafkaBackupHandler } from './backup/kafka-backup.handler';
 import { ZookeeperBackupHandler } from './backup/zookeeper-backup.handler';
@@ -11,7 +12,7 @@ import { UploadsBackupHandler } from './backup/uploads-backup.handler';
 import { MinioStorageAdapter } from './storage/minio-storage.adapter';
 import { LocalStorageAdapter } from './storage/local-storage.adapter';
 import { SnapshotGateway } from '@/api/gateways/snapshot.gateway';
-import { BACKUP_HANDLER_TOKEN } from '@/domain/interfaces/backup-handler.interface';
+import { BackupHandler, BACKUP_HANDLER_TOKEN } from '@/domain/interfaces/backup-handler.interface';
 import { BackupTarget } from '@/domain/enums';
 
 @Module({
@@ -23,6 +24,7 @@ import { BackupTarget } from '@/domain/enums';
     SnapshotGateway,
     // 各备份 handler
     PostgresBackupHandler,
+    MpcPostgresBackupHandler,
     RedisBackupHandler,
     KafkaBackupHandler,
     ZookeeperBackupHandler,
@@ -34,6 +36,7 @@ import { BackupTarget } from '@/domain/enums';
       useFactory: (
         configService: ConfigService,
         pg: PostgresBackupHandler,
+        mpcPg: MpcPostgresBackupHandler,
         redis: RedisBackupHandler,
         kafka: KafkaBackupHandler,
         zk: ZookeeperBackupHandler,
@@ -46,8 +49,8 @@ import { BackupTarget } from '@/domain/enums';
           .map((t) => t.trim())
           .filter(Boolean);
 
-        const allHandlers = [pg, redis, kafka, zk, minio, uploads];
-        const handlerMap = new Map<BackupTarget, PostgresBackupHandler | RedisBackupHandler | KafkaBackupHandler | ZookeeperBackupHandler | MinioBackupHandler | UploadsBackupHandler>();
+        const allHandlers = [pg, mpcPg, redis, kafka, zk, minio, uploads];
+        const handlerMap = new Map<BackupTarget, BackupHandler>();
 
         for (const handler of allHandlers) {
           if (availableTargets.includes(handler.target as string)) {
@@ -60,6 +63,7 @@ import { BackupTarget } from '@/domain/enums';
       inject: [
         ConfigService,
         PostgresBackupHandler,
+        MpcPostgresBackupHandler,
         RedisBackupHandler,
         KafkaBackupHandler,
         ZookeeperBackupHandler,