Projects list cache

backend/handlers/projects.go

@@ -23,16 +23,15 @@ func projectsRouter(router fiber.Router) error {
 	return nil
 }
 
-var projectsLastEdit time.Time;
+var projectsLastEdit time.Time = time.Now().Truncate(time.Second);
 
 func GetAllProjects(c *fiber.Ctx) error {
-	isCached, err := utils.Cache(c, projectsLastEdit);
+	isCached, err := utils.Cache(c, &projectsLastEdit);
 	if err == nil && isCached {
 		return nil;
 	}
 
 	projects, err := db.GetAllProjects()
-	currentTime := time.Now();
 	if err != nil {
 		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
 			"error": "Cannot retrieve projects",
@@ -45,7 +44,6 @@ func GetAllProjects(c *fiber.Ctx) error {
 		return err;
 	}
 
-	projectsLastEdit = currentTime;
 	return nil;
 }
 
@@ -83,6 +81,8 @@ func CreateProject(c *fiber.Ctx) error {
 		})
 	}
 
+	projectsLastEdit = time.Now().Truncate(time.Second);
+
 	return c.Status(fiber.StatusCreated).JSON(fiber.Map{
 		"id": id,
 	})
@@ -111,6 +111,8 @@ func UpdateProject(c *fiber.Ctx) error {
 		return c.SendStatus(fiber.StatusNotFound)
 	}
 
+	projectsLastEdit = time.Now().Truncate(time.Second);
+
 	return c.SendStatus(fiber.StatusNoContent)
 }
 
@@ -132,6 +134,8 @@ func DeleteProject(c *fiber.Ctx) error {
 		return c.SendStatus(fiber.StatusNotFound)
 	}
 
+	projectsLastEdit = time.Now().Truncate(time.Second);
+
 	return c.SendStatus(fiber.StatusNoContent)
 }
 

backend/main.go

@@ -33,7 +33,7 @@ func main() {
 	app.Use(cors.New(cors.Config{
 		AllowOrigins: origins,
 		AllowMethods: "GET,POST,PUT,DELETE",
-		AllowHeaders: "Origin, Content-Type, Accept",
+		AllowHeaders: "Origin, Content-Type, Accept, Cache-Control, Pragma,Expires, If-Modified-Since",
 	}))
 
 	// app.Use(cache.New())

backend/utils/cache.go

@@ -6,16 +6,22 @@ import (
 	"github.com/gofiber/fiber/v2"
 )
 
-func Cache(c *fiber.Ctx, lastEdit time.Time) (bool, error) {
+func Cache(c *fiber.Ctx, lastEdit *time.Time) (bool, error) {
-	clientLast, err := time.Parse(time.RFC1123, c.Get("If-Modified-Since"))
+	ifModifiedSince := c.Get("If-Modified-Since")
+	if ifModifiedSince == "" {
+		return false, nil
+	}
+
+	clientLast, err := time.Parse(time.RFC1123, ifModifiedSince)
 	if err != nil {
 		return false, err
 	}
 
-	if clientLast.Before(lastEdit) {
+	if !lastEdit.After(clientLast) {
 		c.SendStatus(fiber.StatusNotModified)
 		return true, nil
 	}
 
+	c.Set("Last-Modified", lastEdit.Format(time.RFC1123))
 	return false, nil
 }