feat: caching for get all Receipts and cache refresh

Author: putukrisna6

cache/receipt-cache.go

@@ -3,15 +3,17 @@ package cache
 import (
 	"context"
 	"encoding/json"
+	"log"
 	"time"
 
 	"github.com/go-redis/redis/v8"
 	"github.com/putukrisna6/golang-api/entity"
 )
 
 type ReceiptCache interface {
-	Set(key string, value entity.Receipt)
-	Get(key string) entity.Receipt
+	Set(key string, value []entity.Receipt)
+	Get(key string) []entity.Receipt
+	Del(key string)
 }
 
 type receiptCache struct {
@@ -26,7 +28,7 @@ func NewReceiptCache(cache *redis.Client, expires time.Duration) ReceiptCache {
 	}
 }
 
-func (rc *receiptCache) Set(key string, value entity.Receipt) {
+func (rc *receiptCache) Set(key string, value []entity.Receipt) {
 	json, err := json.Marshal(value)
 	if err != nil {
 		panic(err)
@@ -35,20 +37,26 @@ func (rc *receiptCache) Set(key string, value entity.Receipt) {
 	rc.cache.Set(context.TODO(), "receipt:"+key, json, rc.expires*time.Second)
 }
 
-func (rc *receiptCache) Get(key string) entity.Receipt {
+func (rc *receiptCache) Get(key string) []entity.Receipt {
 	val, errGet := rc.cache.Get(context.TODO(), "receipt:"+key).Result()
 
 	if errGet == redis.Nil {
-		return entity.Receipt{}
+		return nil
 	} else if errGet != nil {
 		panic(errGet)
 	}
 
-	receipt := entity.Receipt{}
+	var receipt []entity.Receipt
 	err := json.Unmarshal([]byte(val), &receipt)
 	if err != nil {
 		panic(err)
 	}
 
 	return receipt
 }
+
+func (rc *receiptCache) Del(key string) {
+	err := rc.cache.Del(context.TODO(), "receipt:"+key)
+
+	log.Println(err)
+}

controller/receipt-controller.go

@@ -19,6 +19,7 @@ type ReceiptController interface {
 	Insert(context *gin.Context)
 	Update(context *gin.Context)
 	Delete(context *gin.Context)
+	RefreshCache(keys ...string)
 }
 
 type receiptController struct {
@@ -34,7 +35,12 @@ func NewReceiptController(receiptService service.ReceiptService, receiptCache ca
 }
 
 func (c *receiptController) All(context *gin.Context) {
-	var receipts []entity.Receipt = c.receiptService.All()
+	var receipts []entity.Receipt = c.receiptCache.Get("all")
+	if receipts == nil {
+		receipts = c.receiptService.All()
+		c.receiptCache.Set("all", receipts)
+	}
+
 	res := helper.BuildValidResponse("OK", receipts)
 	context.JSON(http.StatusOK, res)
 }
@@ -47,18 +53,19 @@ func (c *receiptController) Show(context *gin.Context) {
 		return
 	}
 
-	var receipt entity.Receipt = c.receiptCache.Get(strconv.FormatUint(id, 10))
-	if (receipt == entity.Receipt{}) {
+	var arr []entity.Receipt = c.receiptCache.Get(strconv.FormatUint(id, 10))
+	if arr == nil {
 		var receipt entity.Receipt = c.receiptService.Show(id)
 		if (receipt == entity.Receipt{}) {
 			res := helper.BuildErrorResponse("failed to retrieve Receipt", "no data with given receiptID", helper.EmptyObj{})
 			context.AbortWithStatusJSON(http.StatusNotFound, res)
 			return
 		}
-		c.receiptCache.Set(strconv.FormatUint(id, 10), receipt)
+		arr = append(arr, receipt)
+		c.receiptCache.Set(strconv.FormatUint(id, 10), arr)
 	}
 
-	res := helper.BuildValidResponse("OK", receipt)
+	res := helper.BuildValidResponse("OK", arr[0])
 	context.JSON(http.StatusOK, res)
 }
 
@@ -74,6 +81,8 @@ func (c *receiptController) Insert(context *gin.Context) {
 	result := c.receiptService.Insert(receiptCreateDTO)
 	response := helper.BuildValidResponse("OK", result)
 	context.JSON(http.StatusCreated, response)
+
+	c.RefreshCache("all")
 }
 
 func (c *receiptController) Update(context *gin.Context) {
@@ -88,6 +97,8 @@ func (c *receiptController) Update(context *gin.Context) {
 	result := c.receiptService.Update(receiptUpdateDTO)
 	response := helper.BuildValidResponse("OK", result)
 	context.JSON(http.StatusOK, response)
+
+	c.RefreshCache("all", strconv.FormatUint(receiptUpdateDTO.ID, 10))
 }
 
 func (c *receiptController) Delete(context *gin.Context) {
@@ -109,4 +120,12 @@ func (c *receiptController) Delete(context *gin.Context) {
 	message := fmt.Sprintf("Receipt with ID %v successfuly deleted", receipt.ID)
 	res := helper.BuildValidResponse(message, helper.EmptyObj{})
 	context.JSON(http.StatusOK, res)
+
+	c.RefreshCache("all", strconv.FormatUint(id, 10))
+}
+
+func (c *receiptController) RefreshCache(keys ...string) {
+	for _, key := range keys {
+		c.receiptCache.Del(key)
+	}
 }