feat(backend): add cors

backend/internal/handlers/cors.go

@@ -0,0 +1,33 @@
+package handlers
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/gin-gonic/gin"
+	"github.com/samber/lo"
+)
+
+func CorsMiddleware(origincfg string) gin.HandlerFunc {
+	origins := strings.Split(origincfg, ";")
+	if origins[0] == "" {
+		panic("zero cors origins wtf is your config")
+	}
+	return func(c *gin.Context) {
+		origin := c.GetHeader("Origin")
+		if !lo.Contains(origins, origin) {
+			origin = origins[0]
+		}
+		c.Writer.Header().Set("Access-Control-Allow-Origin", origin)
+		// c.Writer.Header().Set("Access-Control-Allow-Credentials", "true")
+		c.Writer.Header().Set("Access-Control-Allow-Headers", "Content-Type, Content-Length, Accept-Encoding, Authorization")
+		c.Writer.Header().Set("Access-Control-Allow-Methods", "OPTIONS, GET, POST, PATCH, DELETE, PUT")
+
+		if c.Request.Method == "OPTIONS" {
+			c.AbortWithStatus(http.StatusNoContent)
+			return
+		}
+
+		c.Next()
+	}
+}