It seems like you're trying to use express middleware in a NestJS microservice application, specifically the express-fingerprint middleware. Unfortunately, you're encountering a challenge because the NestJS microservice application doesn't expose the underlying express instance to directly use the middleware as you're doing.
For the use() method to work, you need to be dealing with an instance of an express-based server, which is not the case when using a microservice in NestJS. When using the microservice method, the NestFactory returns an instance of a microservice, not an HTTP-based server.
However, you can use middleware in a microservice setup by creating hybrid applications which allow you to utilize both HTTP server features (like middleware) and microservice transport layer features. Here's a sample code for such a hybrid application setup:
import { NestFactory } from '@nestjs/core';
import { ExpressAdapter } from '@nestjs/platform-express';
import * as express from 'express';
import { AppModule } from './app.module';
import { MicroserviceOptions, Transport } from '@nestjs/microservices';
import * as Fingerprint from 'express-fingerprint';
async function bootstrap() {
const server = express();
const app = await NestFactory.create(
AppModule,
new ExpressAdapter(server),
);
app.use(
Fingerprint({
parameters: [
Fingerprint.useragent,
Fingerprint.acceptHeaders,
Fingerprint.geoip,
],
}),
);
app.connectMicroservice<MicroserviceOptions>({
transport: Transport.GRPC,
options: {
url: '0.0.0.0:6000',
package: 'protobufPackage',
protoPath: 'node_modules/ecommerce-proto/proto/auth.proto',
},
});
await app.startAllMicroservicesAsync();
await app.listen(3000);
}
bootstrap();
In this code, we first initialize the express server, then create a Nest application using the ExpressAdapter, and lastly, we connect the gRPC microservice to the Nest application.
Hope this helps, and feel free to ask if you have any further questions.
Note: Remember to replace 'protobufPackage' with your actual protobuf package name.
For more about hybrid applications in NestJS, you can check out the official NestJS documentation https://nestjs.com.