This repository is a demonstration application using the E4 Go client library, behind WebAssembly bindings, allowing to expose E4 to JavaScript in a web browser.
It contains:
- WebAssembly bindings to the E4 Go client library (under ./bindings/e4wasm.go)
- A HTML / CSS / JavaScript application (under ./public/)
- A basic web server, to serve files under ./public/ (in ./server.go )
The WebAssembly bindings expose e4js_* methods, directly bound to their respective E4 Go counterparts:
e4js_newClientto create a new E4 cliente4js_protectto protect MQTT messagese4js_unprotectto protect MQTT messagese4js_getControlTopicto retrieve the client control topic
It also embeds a custom storage implementation, interfacing directly with the browser localStorage, that will be used by the E4 clients to persist their state and keys.
The demonstration application aims to simulate IoT devices connected over a MQTT broker, and gives to the user the opportunity to publish and receive messages, either in clear text or protected with E4. It also provides a platform to further test the E4 commercial features from our public demo, such as device provisioning and key rotation, and so without any installation prerequisite.
A Makefile is provided allowing to make build the Wasm bindings as well as the demo web server, and also start a local server for development with make serve.
A Docker container is also available and can be built with
docker build -t e4wasm:latest .
docker run --rm -p 8888:8888 e4wasm:latest
Note that this image is copying all resources inside the container on build, and does not rely on a mounted volume, so it's not aimed to be used for development.