TcpOptions

Kind: Interface

Source: packages/microservices/interfaces/microservice-configuration.interface.ts

Part of: Microservices

TcpOptions configures a NestJS microservice that communicates over the TCP transport. It defines the required transport type and optional connection, retry, serialization, TLS, socket, and buffer settings used when creating the microservice.

Properties

Diagram

mermaid
graph LR
  A[Microservice Configuration] --> B[TcpOptions]
  B --> C[transport: Transport.TCP]
  B --> D[options]
  D --> E[host and port]
  D --> F[retryAttempts and retryDelay]
  D --> G[serializer and deserializer]
  D --> H[tlsOptions]
  D --> I[socketClass]
  D --> J[maxBufferSize]
  E --> K[TCP Microservice Server]

Usage

ts
import { Transport, type TcpOptions } from '@nestjs/microservices';

const tcpConfig: TcpOptions = {
  transport: Transport.TCP,
  options: {
    host: '127.0.0.1',
    port: 3001,
    retryAttempts: 5,
    retryDelay: 1000,
    maxBufferSize: 1024 * 1024,
  },
};

// Example: NestFactory.createMicroservice(AppModule, tcpConfig)

AI Coding Instructions

• Always set transport to Transport.TCP; this interface is specific to TCP-based microservices.
• Configure both host and port explicitly for predictable local, container, and production networking behavior.
• Use retryAttempts and retryDelay when the application must reconnect to TCP dependencies that may start later.
• Provide matching serializer and deserializer implementations when communicating with services that use custom message formats.
• Set tlsOptions, socketClass, or maxBufferSize only when required by the deployment environment or protocol requirements.

How it works

TcpOptions is a public TypeScript interface for configuring a TCP microservice server. It is one member of the MicroserviceOptions union, and its optional transport discriminator is Transport.TCP. Its options object is also optional. microservice-configuration.interface.ts:25-33 microservice-configuration.interface.ts:98-118

The interface itself has no executable validation: every declared property, including options, is optional. microservice-configuration.interface.ts:101-117

When the server factory receives a non-custom configuration whose transport is not one of the explicitly handled non-TCP transports, it constructs ServerTCP with this interface’s options object. server-factory.ts:21-41