# sendJson

> Documentation for Redweb 0.13.3. Install that exact version when following these examples.

Utility to JSON.stringify data and send it over a `ws` socket.

## Explain it like I’m five

sendJson is a careful packer: give it a JavaScript value and it turns that value into one JSON message before placing it on the socket.

## When should I use it?

Use it for structured server-to-client messages instead of repeating JSON.stringify and transport checks throughout handlers.

## Follow the example

This API pattern illustrates the named surface; it may require application-owned classes, credentials, or assets. Start from a complete recipe for a runnable application.

```js
const { sendJson } = require('redweb')

sendJson(socket, { type: 'ping' })
```

1. Application code creates a normal object with a type and payload.
2. sendJson serializes it once using the route’s safe sending path.
3. The client receives one complete text frame and parses the matching JSON value.

## Methods and members

### sendJson(socket, data)

Serialises data and writes it to the socket.

## What should I watch for?

Serialization can fail on cycles and BigInt values, and large objects still consume memory. Bound payload sizes and keep messages purpose-specific.