refactor(identity-service): replace direct RPC with blockchain-service API calls

- Remove ethers.js direct RPC connection to blockchain
- Add HTTP client to call blockchain-service /balance API
- Add ConfigService for BLOCKCHAIN_SERVICE_URL configuration
- Enforce proper microservice boundaries

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

backend/services/identity-service/src/infrastructure/external/blockchain/blockchain-query.service.ts

@@ -1,5 +1,7 @@
 import { Injectable, Logger } from '@nestjs/common';
-import { ethers, JsonRpcProvider, Contract } from 'ethers';
+import { HttpService } from '@nestjs/axios';
+import { ConfigService } from '@nestjs/config';
+import { firstValueFrom } from 'rxjs';
 
 /**
  * USDT 余额查询结果
@@ -13,75 +15,49 @@ export interface UsdtBalance {
 }
 
 /**
- * 链配置
+ * blockchain-service 余额响应
  */
-interface ChainConfig {
+interface BlockchainBalanceResponse {
-  rpcUrl: string;
+  chainType: string;
-  usdtContract: string;
+  address: string;
-  decimals: number;
+  usdtBalance: string;
-  name: string;
+  nativeBalance: string;
+  nativeSymbol: string;
 }
 
 /**
- * ERC20 合约 ABI (仅需 balanceOf)
+ * blockchain-service 多链余额响应
  */
-const ERC20_ABI = [
+interface BlockchainMultiChainResponse {
-  'function balanceOf(address owner) view returns (uint256)',
+  address: string;
-  'function decimals() view returns (uint8)',
+  balances: BlockchainBalanceResponse[];
-];
+}
 
 /**
  * 区块链查询服务
  *
- * 用于查询 KAVA EVM 和 BSC 链上的 USDT 余额
+ * 通过 HTTP 调用 blockchain-service 查询余额
  */
 @Injectable()
 export class BlockchainQueryService {
   private readonly logger = new Logger(BlockchainQueryService.name);
+  private readonly blockchainServiceUrl: string;
 
-  /**
+  // 链的 decimals 配置
-   * 链配置
+  private readonly chainDecimals: Record<string, number> = {
-   */
+    KAVA: 6,
-  private readonly chainConfigs: Record<string, ChainConfig> = {
+    BSC: 18,
-    KAVA: {
-      rpcUrl: process.env.KAVA_RPC_URL || 'https://evm.kava.io',
-      // KAVA EVM 原生 USDT 合约地址 (Tether 官方发行)
-      usdtContract: '0x919C1c267BC06a7039e03fcc2eF738525769109c',
-      decimals: 6,
-      name: 'KAVA EVM',
-    },
-    BSC: {
-      rpcUrl: process.env.BSC_RPC_URL || 'https://bsc-dataseed.binance.org',
-      // BSC USDT 合约地址 (Binance-Peg)
-      usdtContract: '0x55d398326f99059fF775485246999027B3197955',
-      decimals: 18,
-      name: 'BSC',
-    },
   };
 
-  /**
+  constructor(
-   * Provider 缓存
+    private readonly httpService: HttpService,
-   */
+    private readonly configService: ConfigService,
-  private providers: Map<string, JsonRpcProvider> = new Map();
+  ) {
-
+    this.blockchainServiceUrl = this.configService.get<string>(
-  /**
+      'BLOCKCHAIN_SERVICE_URL',
-   * 获取或创建 Provider
+      'http://blockchain-service:3000',
-   */
+    );
-  private getProvider(chainType: string): JsonRpcProvider {
+    this.logger.log(`BlockchainQueryService initialized, URL: ${this.blockchainServiceUrl}`);
-    if (this.providers.has(chainType)) {
-      return this.providers.get(chainType)!;
-    }
-
-    const config = this.chainConfigs[chainType];
-    if (!config) {
-      throw new Error(`不支持的链类型: ${chainType}`);
-    }
-
-    const provider = new JsonRpcProvider(config.rpcUrl, undefined, {
-      staticNetwork: true,
-    });
-    this.providers.set(chainType, provider);
-    return provider;
   }
 
   /**
@@ -91,36 +67,33 @@ export class BlockchainQueryService {
    * @param address EVM 地址
    */
   async getUsdtBalance(chainType: string, address: string): Promise<UsdtBalance> {
-    const config = this.chainConfigs[chainType];
-    if (!config) {
-      throw new Error(`不支持的链类型: ${chainType}`);
-    }
-
-    // 验证地址格式
-    if (!ethers.isAddress(address)) {
-      throw new Error(`无效的 EVM 地址: ${address}`);
-    }
-
     try {
-      this.logger.debug(`查询 ${config.name} USDT 余额: ${address}`);
+      this.logger.debug(`查询 ${chainType} USDT 余额: ${address}`);
 
-      const provider = this.getProvider(chainType);
+      const response = await firstValueFrom(
-      const contract = new Contract(config.usdtContract, ERC20_ABI, provider);
+        this.httpService.get<BlockchainBalanceResponse>(
+          `${this.blockchainServiceUrl}/balance`,
+          {
+            params: {
+              chainType,
+              address,
+            },
+          },
+        ),
+      );
 
-      const rawBalance = await contract.balanceOf(address);
+      const data = response.data;
-      const balance = ethers.formatUnits(rawBalance, config.decimals);
+      this.logger.debug(`${chainType} USDT 余额: ${data.usdtBalance}`);
-
-      this.logger.debug(`${config.name} USDT 余额: ${balance}`);
 
       return {
-        chainType,
+        chainType: data.chainType,
-        address,
+        address: data.address,
-        balance,
+        balance: data.usdtBalance,
-        rawBalance: rawBalance.toString(),
+        rawBalance: this.toRawBalance(data.usdtBalance, chainType),
-        decimals: config.decimals,
+        decimals: this.chainDecimals[chainType] || 6,
       };
     } catch (error) {
-      this.logger.error(`查询 ${config.name} USDT 余额失败: ${error.message}`);
+      this.logger.error(`查询 ${chainType} USDT 余额失败: ${error.message}`);
       throw new Error(`查询余额失败: ${error.message}`);
     }
   }
@@ -148,7 +121,7 @@ export class BlockchainQueryService {
         address: addresses[index].address,
         balance: '0',
         rawBalance: '0',
-        decimals: this.chainConfigs[addresses[index].chainType]?.decimals || 6,
+        decimals: this.chainDecimals[addresses[index].chainType] || 6,
       };
     });
   }
@@ -157,22 +130,38 @@ export class BlockchainQueryService {
    * 查询原生代币余额 (KAVA / BNB)
    */
   async getNativeBalance(chainType: string, address: string): Promise<string> {
-    const config = this.chainConfigs[chainType];
-    if (!config) {
-      throw new Error(`不支持的链类型: ${chainType}`);
-    }
-
-    if (!ethers.isAddress(address)) {
-      throw new Error(`无效的 EVM 地址: ${address}`);
-    }
-
     try {
-      const provider = this.getProvider(chainType);
+      const response = await firstValueFrom(
-      const rawBalance = await provider.getBalance(address);
+        this.httpService.get<BlockchainBalanceResponse>(
-      return ethers.formatEther(rawBalance);
+          `${this.blockchainServiceUrl}/balance`,
+          {
+            params: {
+              chainType,
+              address,
+            },
+          },
+        ),
+      );
+
+      return response.data.nativeBalance;
     } catch (error) {
-      this.logger.error(`查询 ${config.name} 原生代币余额失败: ${error.message}`);
+      this.logger.error(`查询 ${chainType} 原生代币余额失败: ${error.message}`);
       throw new Error(`查询余额失败: ${error.message}`);
     }
   }
+
+  /**
+   * 将格式化余额转换为原始余额 (wei)
+   */
+  private toRawBalance(formattedBalance: string, chainType: string): string {
+    try {
+      const decimals = this.chainDecimals[chainType] || 6;
+      const [intPart, decPart = ''] = formattedBalance.split('.');
+      const paddedDecPart = decPart.padEnd(decimals, '0').slice(0, decimals);
+      const rawValue = BigInt(intPart + paddedDecPart);
+      return rawValue.toString();
+    } catch {
+      return '0';
+    }
+  }
 }

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

@@ -1,5 +1,6 @@
 import { Module, Global } from '@nestjs/common';
 import { HttpModule } from '@nestjs/axios';
+import { ConfigModule } from '@nestjs/config';
 import { PrismaService } from './persistence/prisma/prisma.service';
 import { UserAccountRepositoryImpl } from './persistence/repositories/user-account.repository.impl';
 import { MpcKeyShareRepositoryImpl } from './persistence/repositories/mpc-key-share.repository.impl';
@@ -17,6 +18,7 @@ import { WalletGeneratorService } from '@/domain/services/wallet-generator.servi
 @Global()
 @Module({
   imports: [
+    ConfigModule,
     HttpModule.register({
       timeout: 300000,
       maxRedirects: 5,