strata_admin/websocket

Browser WebSocket bridge for the admin SPA.

Types

SendError

Why the admin app could not send a text frame.

pub type SendError {
  SocketNotOpen
}

Socket

An opaque handle for a native browser WebSocket connection.

pub type Socket

WsEvent

An opaque handle for a browser WebSocket event object passed to callbacks.

pub type WsEvent

Functions

close

Start the browser WebSocket close operation.

pub fn close(Socket) -> Nil

open_socket

Open a browser WebSocket and return its handle immediately.

The browser calls on_open when the connection opens. It calls on_message for each message and calls on_close for a close or error event.

pub fn open_socket(
  String,
  fn(WsEvent) -> Nil,
  fn(String) -> Nil,
  fn(WsEvent) -> Nil
) -> Socket

query_param

Return a query parameter from the current page URL.

Return an empty string if the parameter is absent or empty.

pub fn query_param(String) -> String

register_open

Register a callback for the next open event.

The browser calls the callback at most once.

pub fn register_open(
  Socket,
  fn() -> Nil
) -> Nil

send

Send one text frame. Returns Error(SocketNotOpen) when the browser socket is not open.

pub fn send(
  Socket,
  String
) -> Result(Nil, SendError)

websocket_url

Build the admin WebSocket URL for the current page host.

The function uses wss on an HTTPS page and ws on another page. It adds the token as one encoded query parameter.

pub fn websocket_url(String) -> String