WebSocket Relay Server is an API application hosted on Qoosky. Devices such as Raspberry Pi, Arduino, and Android Things can be controlled in real-time through the Internet using the API from PCs and smartphones.
- API token is required to connect to the server, which is described in this page: https://www.qoosky.dev/docs/apis/
- WebSocket client samples are available here https://github.com/qoosky/websocket-clients
WebSocket clients such as the IoT devices and keypad JavaScript application upgrade their HTTP connections to communicate over the WebSocket protocol with Akka HTTP server. Inside Akka HTTP server, there exist two types of actors: Actuator for the IoT devices and Keypad for the JavaScript application. An Actuator actor first sends ConnectionRequest to the Keypad actors, and some Keypad actor replies if it has the same API token as the Actuator actor.
Once the Actuator actor and the Keypad actor are connected, they can send and receive WebSocket messages as if they were directly connected, but in fact there exists the intermediate Akka HTTP relay server.
Java 11 and SBT 1.3.4 or higher need to be installed. You can test, run, and build the application using the following commands. No middleware is required.
Run unit tests
sbt test
Run application at http://localhost:8080/
sbt run
Build fat JAR
sbt assembly
java -jar target/scala-2.13/websocket-relay-server-assembly-1.1.jar
The MIT License (MIT)
Copyright (c) 2020 Qoosky
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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