WsResponse

Kind: Interface

Source: packages/websockets/interfaces/ws-response.interface.ts

Part of: Websockets

WsResponse<T> defines the standard envelope for messages sent through the WebSocket layer. It pairs an event name with typed data, allowing clients and servers to route and process real-time responses consistently.

Properties

Diagram

mermaid
graph LR
  Server[WebSocket Server] --> Response[WsResponse<T>]
  Response --> Event[event: string]
  Response --> Data[data: T]
  Response --> Client[WebSocket Client]

Usage

ts
import type { WsResponse } from './interfaces/ws-response.interface';

interface UserConnectedPayload {
  userId: string;
  connectedAt: string;
}

const response: WsResponse<UserConnectedPayload> = {
  event: 'user.connected',
  data: {
    userId: 'user_123',
    connectedAt: new Date().toISOString(),
  },
};

socket.emit(response.event, response.data);

AI Coding Instructions

• Use WsResponse<T> for WebSocket response payloads to keep event names and data consistently structured.
• Define a dedicated payload interface or type for T instead of using any.
• Keep event values stable and descriptive, such as user.connected or message.created.
• Emit the event and payload using socket.emit(response.event, response.data) when the transport expects separate arguments.
• Ensure client-side listeners use the same event name and payload type as the corresponding response.

How it works

WsResponse<T = any> is a public TypeScript interface for an object with two required fields: event, a string, and data, whose type is the generic parameter T (defaulting to any). [packages/websockets/interfaces/ws-response.interface.ts:1-7]

It is re-exported through the interfaces barrel and the package root, so it is available from @nestjs/websockets. [packages/websockets/interfaces/index.ts:1-5] [packages/websockets/index.ts:9-14]

The interface has no methods or runtime implementation; the shown declaration contains no validation, error handling, or side effects. [packages/websockets/interfaces/ws-response.interface.ts:4-7]

In the gateway sample, a message handler is typed as returning Observable<WsResponse<number>> and maps 1, 2, and 3 into objects shaped as { event: 'events', data: item }. [sample/02-gateways/src/events/events.gateway.ts:21-24]

Used by

2 references from 2 files. Each is a place in this repository where the symbol is actually used — go read one rather than trusting an example.

Imported by (2)

• EventsGateway — sample/02-gateways/src/events/events.gateway.ts:12
• EventsGateway — sample/16-gateways-ws/src/events/events.gateway.ts:11