A ScreneGraph websocket client library written in BrightScript. It is written to work in a separate task to not affect the main thread of the application.

Many thanks to rolandoislas/BrightWebSocket who originally developed this library.

RFC 6455

Follows RFC 6455

Notes:

• Uses ASCII instead of UTF-8 for string operations
• Does not support secure web sockets at this time

Installation

The contents of the "src" folder in the repository's root should be placed in the "components" folder of a SceneGraph Roku app.

Using the Library

The client follows the HTML WebSocket interface, modified to work with BrightScript conventions. Those familiar with browser (JavaScript) WebSocket implementations should find this client similar.

Example:

function init() as void
    m.ws = createObject("roSGNode", "WebSocketClient")
    m.ws.observeField("on_open", "on_open")
    m.ws.observeField("on_message", "on_message")
    m.ws.open = "ws://echo.websocket.org/"
end function

function on_open(event as object) as void
    m.ws.send = ["Hello World"]
end function

function on_message(event as object) as void
    print event.getData().message
end function

For a working sample app see the "test" folder. Its contents can be zipped for installation as a dev channel on a Roku.

Additional information

A differences between roUrlTransfer and roStreamSocket

The roUrltransfer is sending larger data faster, Roku replied to this with the following:

Could be the difference between using curlLibrary and lower-level roStreamSocket implementation. The curl library is highly optimized as we use it for all the manifest handling in streaming.

The roStreamSocket is separated into standalone thread but still is serialized, devices handling a higher amount of data could overload a buffer for some situations and data could send for longer.

We approximately measured 230KB/s on 4660X - Roku Ultra and 15KB/s on 3500EU - Roku Stick.

To send larger amount of data we suggest to use roUrlTransfer instead. Won't be improved/fixed in near future.

License

The MIT License. See license.txt.