method ClientRequest.prototype.getRawHeaderNames
Usage in Deno
```typescript import { ClientRequest } from "node:node__http.d.ts"; ```
ClientRequest.prototype.getRawHeaderNames(): string[]
Returns an array containing the unique names of the current outgoing raw
headers. Header names are returned with their exact casing being set.
```js
request.setHeader('Foo', 'bar');
request.setHeader('Set-Cookie', ['foo=bar', 'bar=baz']);
const headerNames = request.getRawHeaderNames();
// headerNames === ['Foo', 'Set-Cookie']
```
string[]