Outline

Library for remote transmission of data on Stream objects. (using @andyfischer/streams).

Each connection is multiplexed so it can support multiple streams at once. For example, the HTTP client can receive data for multiple Streams as part of a single HTTP request.

Supports a few builtin transport types and supports custom transports.

Provides a generic Connection interface, so that most of the code can be agnostic about what the connection's transport is.

Builtin transports

• HttpClient - Client using fetch to make HTTP requests.
• MessagePort - Client using Javascript MessagePort objects (used in web workers)
• WebSocket - Client using a WebSocket connection.
• HttpServer - Server that handles HTTP requests.
• WebSocketServer - Server that handles WebSocket connections.

Overview

Each remote connection has two layers:

• Connection layer

  • Implemented by the Connection class.
  • Same class used for all types of protocols.
  • Handles multiplexing of request & response streams across the transport.
  • Handles the connection state (connected / closed / etc)
  • Handles creating the Transport as needed.
  • Handles queueing of incoming messages if we're waiting to establish the connection.

• Transport layer

  • Seperate implementations for different protocols: HTTP, WebSocket, etc.
  • Lower level, handles the details of sending the message across some remote protocol.
  • Responsible for transporting messages to & from the Connection.

How to write a new Transport

The transport interface looks like:

interface ConnectionTransport<RequestType, ResponseType> {
    send(message: TransportMessage<RequestType>): void
    incomingEvents: Stream< TransportMessage<RequestType> >
    close(): void
}