Coral is a small library which aims to have the same workflow as SocketIO.
- golang 1.16+
Install the library in your go project :
go get -u github.com/go-gems/coral
Then in your projects you have to implement a web server and on a route call the Coral.handle method. For example on a vanilla http server :
package main
import (
"github.com/go-gems/coral"
"net/http"
)
func main() {
// handle coral requests on /ws.
http.HandleFunc("/ws", func(writer http.ResponseWriter, request *http.Request) {
if err := Coral.Handle(writer, request); err != nil {
panic(err)
}
})
// serve a public directory on /
http.Handle("/", http.FileServer(http.Dir("./public")))
http.ListenAndServe(":8080", nil)
}the example folder contains the implement with gin.
You can now listen on every websocket connection:
//event to do when user joins the server.
Coral.OnConnection(func(conn *Coral.Conn) error {
log.Println("connection established")
//Broadcast to every user.
Coral.Broadcast("user:joined","Somebody joined!")
//conn Object represents a single user connected.
//When conn sends a "says" type (or anything you want type)
conn.On("says", func(content interface{}) error {
//broadcast to all except sender
conn.Broadcast("listen", content)
return nil
})
// When conn sends a "ping" message.
conn.On("ping", func(content interface{}) error {
//Forward to all except conn.
return conn.Emit("pong", content)
})
return nil
})Javascript side, you can use the Coral.js which is the beginning of a library - and thus will be published as a npm package. Example usage :
<!doctype html>
<html>
<body>
<h1>Coral Demo.</h1>
<script type="module" src="script.js"></script>
</body>
</html>and in script.js.
import Coral from "./Coral.js";
//coral communication instance
//default connection to same host/ws
const coral = new Coral()
// if needed
// const coral = new Coral({url: "ws://test.com/something"})
//on connection open
coral.onOpen = function () {
console.log("connection established");
// on message recieved on listen
coral.on("listen", (msg) => {
console.log("received message ", msg)
})
coral.on("user:joined", (msg)=>{
console.log(msg);
coral.emit("says","Hello new User.");
})
coral.on("pong", (msg) => {
console.log("PONG", msg)
})
coral.emit("ping","Hello");
}And that's all for now!
If you like the project, feel free to contribute, there are plenty of things to do :
- Transform coral.js as a npm library
- Add Channels management (WIP)
So every PR is welcome.