我正在尝试构建一个包含多个微服务的 NestJS 后端和一个作为与微服务通信的网关的 REST API。对于网关和微服务之间的通信,我使用 gRPC。
简单的通信已经可以工作,但现在我想在微服务中实现错误处理。
NestJS 文档指出,这可以通过 RpcException 类实现。https://docs.nestjs.com/microservices/exception-filters但是,如果我尝试捕获网关 API 中的异常,我只会收到“ERROR [ExceptionsHandler] 2 UNKNOWN: ...”,后面跟着异常错误消息。
网关API:
用户控制器.ts
import { Controller, Get, Param } from '@nestjs/common';
import { ApiTags } from '@nestjs/swagger';
import { UserViewModel } from '../../proto/build/service-name/user';
import { UserService } from './user.service';
@Controller('user')
export class UserController {
constructor(private readonly userService: UserService) {}
@Get(':id')
async getUserById(@Param('id') id: number): Promise<UserViewModel> {
try {
return await this.userService.getUserById(id);
} catch (error) {
return error;
}
}
}
网关API:
用户服务.ts
import { Inject, Injectable, OnModuleInit } from '@nestjs/common';
import { ClientGrpc } from '@nestjs/microservices';
import {
IUserService,
UserViewModel,
} from '../../proto/build/service-name/user';
@Injectable()
export class UserService implements OnModuleInit {
private grpcService: IUserService;
constructor(@Inject('USER_PACKAGE') private client: ClientGrpc) {}
onModuleInit() {
this.grpcService = this.client.getService<IUserService>('IUserService');
}
async getUserById(id: number): Promise<UserViewModel> {
return this.grpcService.getUserById({ id });
}
}
微服务:
用户控制器.ts
import { Metadata } from '@grpc/grpc-js';
import { Controller } from '@nestjs/common';
import { GrpcMethod, RpcException } from '@nestjs/microservices';
import { User } from './../../node_modules/.prisma/client/index.d';
import { PrismaService } from '../prisma/prisma.service';
import { UserViewModel, GetUserById } from '../proto/build/service-name/user';
@Controller()
export class UserController {
constructor(private readonly prisma: PrismaService) {}
@GrpcMethod('IUserService', 'getUserById')
async getUserById(
data: GetUserById,
metadata: Metadata,
): Promise<UserViewModel> {
const user: User = await this.prisma.user.findFirst({
where: { id: { equals: data.id } },
});
if (!user) {
throw new RpcException('User not found');
}
return { name: user.name, email: user.email };
}
}