Get wasm grpc port and hostname at runtime

Author: salvacorts

mlp-ea-decentralized/common/ga/poolModel.go

@@ -347,7 +347,11 @@ func (pool *PoolModel) handleEvaluate() {
 
 	// Setup HTTP listener to serve webs
 	Log.Infof("Web Server for bowser collaborators at http://%s:%d/", listenAddr, wasmPort)
-	go http.ListenAndServe(fmt.Sprintf("%s:%d", listenAddr, webPort), http.FileServer(http.Dir(pool.WebPath)))
+	http.Handle("/", http.FileServer(http.Dir(pool.WebPath)))
+	http.HandleFunc("/grpcPortWS", func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprintf(w, "%d", wasmPort)
+	})
+	go http.ListenAndServe(fmt.Sprintf("%s:%d", listenAddr, webPort), nil)
 
 	// Setup listener for wasm clients based on websockets
 	lisWasm, err := ws.Listen(fmt.Sprintf("ws://%s:%d", listenAddr, wasmPort), nil)

mlp-ea-decentralized/web/src/go/main.go

@@ -1,8 +1,12 @@
 package main
 
 import (
+	"fmt"
+	"io/ioutil"
 	"log"
 	"net"
+	"net/http"
+	"syscall/js"
 	"time"
 
 	"github.com/dennwc/dom/net/ws"
@@ -15,27 +19,39 @@ import (
 func main() {
 	log.SetOutput(WebLogger{})
 
-	logger := WebLogger{}
+	// Ask for served grpc port
+	resp, err := http.Get("/grpcPortWS")
+	if err != nil {
+		log.Fatalf("Could not ask for grpcPort. %s", err.Error())
+	}
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		log.Fatalf("Could not read Body. %s", err.Error())
+	}
 
 	client := ga.Client{
-		ServerAddr: "ws://127.0.0.1:2019",
-		ID:         "clientWasm",
-		Log:        logrus.New(),
-		Delegate:   mlp.DelegateImpl{},
+		ID:       "clientWasm",
+		Log:      logrus.New(),
+		Delegate: mlp.DelegateImpl{},
 
 		// Use WebSockets
 		CustomDialer: func(s string, dt time.Duration) (net.Conn, error) {
 			return ws.Dial(s)
 		},
 	}
 
+	logger := WebLogger{}
 	logrus.SetOutput(logger)
 	logrus.SetLevel(logrus.ErrorLevel)
 	client.Log.SetOutput(logger)
 	client.Log.SetLevel(logrus.InfoLevel)
 	client.Log.SetFormatter(&logrus.JSONFormatter{})
 
-	err := client.Start()
+	host := js.Global().Call("GetHostName")
+	client.Log.Infof("Hostname: %s", host.String())
+	client.ServerAddr = fmt.Sprintf("ws://%s:%s", host.String(), string(body))
+
+	err = client.Start()
 	if err != nil {
 		client.Log.Fatalf("Got error from client: %s", err.Error())
 	}

mlp-ea-decentralized/web/src/go/wasm/main.wasm

@@ -1,5 +1,9 @@
 importScripts("wasm_exec.js")
 
+function GetHostName() {
+    return self.location.hostname
+}
+
 if (!WebAssembly.instantiateStreaming) { // polyfill
     WebAssembly.instantiateStreaming = async (resp, importObject) => {
         const source = await (await resp).arrayBuffer();