OptionalWebSocketConstructor
WebSocketConstructor?: { 
    CLOSED: 3; 
    CLOSING: 2; 
    CONNECTING: 0; 
    OPEN: 1; 
    prototype: WebSocket; 
    new (url: string | URL, protocols?: string | string[]): WebSocket; 
}
Optionalfetch
fetch?: { 
    (input: RequestInfo | URL, init?: RequestInit): Promise<Response>; 
    (input: string | Request | URL, init?: RequestInit): Promise<Response>; 
}
Type declaration
- (input, init?): Promise<Response>
 Parameters
- input: RequestInfo | URL
 Optionalinit: RequestInit
Returns Promise<Response>
- (input, init?): Promise<Response>
 Parameters
- input: string | Request | URL
 Optionalinit: RequestInit
Returns Promise<Response>
Optionalrpc
url
url: string
Optionalwebsocket
websocket?: WebsocketClientOptions & { 
    url?: string; 
}
MDN Reference