GO & Gin: Use the same gin router to mount embedded frontend and your API routes

frontendRoutes.go

package main

/*
Uses the same gin router to mount embedded frontend.

Change the //go:embed .\frontend
Change the `root, _ := fs.Sub(embedFrontendFS, "frontend")`
*/

import (
	"embed"
	"io/fs"
	"net/http"

	"github.com/gin-gonic/gin"
)

var (
	//go:embed .\frontend
	embedFrontendFS embed.FS
)

func embedFrontend(router *gin.Engine, httpPrefix string) {
  // This works only if mounted on a subroute like "/static"
  // if mounted in "/" there will be conflicts with your "/api/*"
	// root, _ := fs.Sub(embedFrontendFS, "frontend")
	// router.StaticFS("/static", http.FS(root))

  // This second approach works just fine
	root, _ := fs.Sub(embedFrontendFS, "frontend") // Set root folder inside embed tree
	fileserver := http.FileServer(http.FS(root))
	fileserver = http.StripPrefix(httpPrefix, fileserver)
	router.Use(func(c *gin.Context) {
		fileserver.ServeHTTP(c.Writer, c.Request)
		c.Abort()
	})
}

main.go

package main

import (
	"myProject/controllers"
	"myProject/initializers"
	"myProject/models"
	"log"
	"os"

	"github.com/gin-gonic/gin"
)

func init() { // GO built-in function, executed on package import, just before `main`
	initializers.LoadEnvVars()
	gin.SetMode(os.Getenv("GIN_MODE"))
}

func main() {
	db := initializers.NewDbConnection()
	if os.Getenv("GORM_LOG_ALL_QUERYS") == "true" {
		db = db.Debug() // Log out ALL SQL querryes
	}

	controllers.SetDBConnection(db)
	models.SetDBConnection(db)

	router := gin.Default()
	setupRoutes(router)        // API routes
	embedFrontend(router, "/") // File server Routes <-- THIS IS WHAT YOU ARE LOOKING FOR

	go router.Run() // Start server in a separate thread

	ConsoleLoop() // Use my commands in console while server is runnung

	log.Println("🖥️  Servidor de reportes detenido.\nBye.")
}