fix(gateway): added CORS middleware to allow all origins

Closes: #27
Signed-off-by: Klagarge <remi@heredero.ch>

gateway/src/Connection.go

@@ -4,6 +4,7 @@ import (
 	_ "crypto/md5"
 	_ "gateway-softweng/docs"
 	paho "github.com/eclipse/paho.mqtt.golang"
+	"github.com/gin-contrib/cors"
 	"github.com/gin-gonic/gin"
 	influxdb2 "github.com/influxdata/influxdb-client-go/v2"
 	"github.com/influxdata/influxdb-client-go/v2/api"
@@ -78,6 +79,13 @@ func (gh *Gateway) createRestGateway() {
 	// Create a new Gin router
 	gh.rest = gin.Default()
 
+	// Configure CORS middleware to allow all origins
+	config := cors.DefaultConfig()
+	config.AllowAllOrigins = true
+	config.AllowMethods = []string{"GET", "POST"}
+	config.AllowHeaders = []string{"Origin", "Content-Length", "Content-Type", "Authorization"}
+	gh.rest.Use(cors.New(config))
+
 	gh.rest.GET("/ping", pingHandler)
 
 	// Swagger documentation route