method ServerHttp2Session.altsvc
Usage in Deno
```typescript import { type ServerHttp2Session } from "node:node__http2.d.ts"; ```
ServerHttp2Session.altsvc(alt: string,originOrStream: ,): void
Submits an `ALTSVC` frame (as defined by [RFC 7838](https://tools.ietf.org/html/rfc7838)) to the connected client.
```js
import http2 from 'node:http2';
const server = http2.createServer();
server.on('session', (session) => {
// Set altsvc for origin https://example.org:80
session.altsvc('h2=":8000"', 'https://example.org:80');
});
server.on('stream', (stream) => {
// Set altsvc for a specific stream
stream.session.altsvc('h2=":8000"', stream.id);
});
```
Sending an `ALTSVC` frame with a specific stream ID indicates that the alternate
service is associated with the origin of the given `Http2Stream`.
The `alt` and origin string _must_ contain only ASCII bytes and are
strictly interpreted as a sequence of ASCII bytes. The special value `'clear'`may be passed to clear any previously set alternative service for a given
domain.
When a string is passed for the `originOrStream` argument, it will be parsed as
a URL and the origin will be derived. For instance, the origin for the
HTTP URL `'https://example.org/foo/bar'` is the ASCII string`'https://example.org'`. An error will be thrown if either the given string
cannot be parsed as a URL or if a valid origin cannot be derived.
A `URL` object, or any object with an `origin` property, may be passed as`originOrStream`, in which case the value of the `origin` property will be
used. The value of the `origin` property _must_ be a properly serialized
ASCII origin.
void