Add caching

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/knadh/koanf v0.15.0
 	github.com/labstack/echo/v4 v4.2.1
 	github.com/mitchellh/copystructure v1.1.1 // indirect
+	github.com/patrickmn/go-cache v2.1.0+incompatible // indirect
 	github.com/rs/zerolog v1.20.0
 	golang.org/x/sys v0.0.0-20210309074719-68d13333faf2 // indirect
 	golang.org/x/text v0.3.5 // indirect

go.sum

@@ -212,6 +212,8 @@ github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRW
 github.com/oklog/run v1.0.0/go.mod h1:dlhp/R75TPv97u0XWUtDeV/lRKWPKSdTuV0TZvrmrQA=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
 github.com/pascaldekloe/goe v0.1.0/go.mod h1:lzWF7FIEvWOWxwDKqyGYQf6ZUaNfKdP144TG7ZOy1lc=
+github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
+github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/pelletier/go-toml v1.7.0 h1:7utD74fnzVc/cpcyy8sjrlFr5vYpypUixARcHIMIGuI=
 github.com/pelletier/go-toml v1.7.0/go.mod h1:vwGMzjaWMwyfHwgIBhI2YUM4fB6nL6lVAvS1LBMMhTE=

link/handlers.go

@@ -8,11 +8,9 @@ import (
 	"strconv"
 )
 
-func redirectHandler(c echo.Context, pool *pgxpool.Pool) error {
+func redirectHandler(c echo.Context, serv *PgService) error {
 	linkId := c.Param("id")
 
-	serv := PgService{rep: PgRepository{pool: pool}}
-
 	link, err := serv.GetById(linkId)
 	if err != nil {
 		return err
@@ -21,7 +19,7 @@ func redirectHandler(c echo.Context, pool *pgxpool.Pool) error {
 	return c.Redirect(http.StatusSeeOther, link.RedirectURL.String())
 }
 
-func creationHandler(c echo.Context, pool *pgxpool.Pool) error {
+func creationHandler(c echo.Context, serv *PgService) error {
 	var model CreationModel
 	if err := json.NewDecoder(c.Request().Body).Decode(&model); err != nil {
 		return echo.NewHTTPError(http.StatusBadRequest, "Invalid data format.")
@@ -32,8 +30,6 @@ func creationHandler(c echo.Context, pool *pgxpool.Pool) error {
 		return echo.NewHTTPError(http.StatusBadRequest, "Invalid URL.")
 	}
 
-	serv := PgService{rep: PgRepository{pool: pool}}
-
 	if err = serv.Create(entity); err != nil {
 		return err
 	}
@@ -41,11 +37,9 @@ func creationHandler(c echo.Context, pool *pgxpool.Pool) error {
 	return c.NoContent(http.StatusCreated)
 }
 
-func retrievalByIdHandler(c echo.Context, pool *pgxpool.Pool) error {
+func retrievalByIdHandler(c echo.Context, serv *PgService) error {
 	linkId := c.Param("id")
 
-	serv := PgService{rep: PgRepository{pool: pool}}
-
 	l, err := serv.GetById(linkId)
 	if err != nil {
 		return err
@@ -54,7 +48,7 @@ func retrievalByIdHandler(c echo.Context, pool *pgxpool.Pool) error {
 	return c.JSON(http.StatusOK, MapEntityToModel(l))
 }
 
-func allRetrievalHandler(c echo.Context, pool *pgxpool.Pool) error {
+func allRetrievalHandler(c echo.Context, serv *PgService) error {
 	limit := 20
 	if v := c.QueryParam("limit"); v != "" {
 		num, err := strconv.Atoi(v)
@@ -75,8 +69,6 @@ func allRetrievalHandler(c echo.Context, pool *pgxpool.Pool) error {
 		offset = num
 	}
 
-	serv := PgService{rep: PgRepository{pool: pool}}
-
 	links, err := serv.GetAll(limit, offset)
 	if err != nil {
 		return err
@@ -90,11 +82,9 @@ func allRetrievalHandler(c echo.Context, pool *pgxpool.Pool) error {
 	return c.JSON(http.StatusOK, models)
 }
 
-func removalHandler(c echo.Context, pool *pgxpool.Pool) error {
+func removalHandler(c echo.Context, serv *PgService) error {
 	linkId := c.Param("id")
 
-	serv := PgService{rep: PgRepository{pool: pool}}
-
 	if err := serv.DeleteById(linkId); err != nil {
 		return err
 	}
@@ -103,25 +93,27 @@ func removalHandler(c echo.Context, pool *pgxpool.Pool) error {
 }
 
 func AddHandlers(s *echo.Echo, pool *pgxpool.Pool) {
+	serv := NewPgService(PgRepository{pool: pool})
+
 	gr := s.Group("/links")
 
 	gr.POST("", func(ctx echo.Context) error {
-		return creationHandler(ctx, pool)
+		return creationHandler(ctx, &serv)
 	})
 
 	gr.GET("", func(ctx echo.Context) error {
-		return allRetrievalHandler(ctx, pool)
+		return allRetrievalHandler(ctx, &serv)
 	})
 
 	gr.GET("/:id", func(ctx echo.Context) error {
-		return retrievalByIdHandler(ctx, pool)
+		return retrievalByIdHandler(ctx, &serv)
 	})
 
 	gr.DELETE("/:id", func(ctx echo.Context) error {
-		return removalHandler(ctx, pool)
+		return removalHandler(ctx, &serv)
 	})
 
 	s.GET("/:id", func(ctx echo.Context) error {
-		return redirectHandler(ctx, pool)
+		return redirectHandler(ctx, &serv)
 	})
 }

link/service.go

@@ -2,6 +2,8 @@ package link
 
 import (
 	apperrors "cgnolink/errors"
+	"github.com/patrickmn/go-cache"
+	"time"
 )
 
 type Service interface {
@@ -12,7 +14,15 @@ type Service interface {
 }
 
 type PgService struct {
-	rep PgRepository
+	rep   PgRepository
+	cache *cache.Cache
+}
+
+func NewPgService(rep PgRepository) PgService {
+	return PgService{
+		rep:   rep,
+		cache: cache.New(1*time.Hour, 90*time.Minute),
+	}
 }
 
 func (s *PgService) Create(link *Link) error {
@@ -33,6 +43,12 @@ func (s *PgService) Create(link *Link) error {
 }
 
 func (s *PgService) GetById(id string) (*Link, error) {
+	if v, found := s.cache.Get(id); found {
+		if link, ok := v.(*Link); ok {
+			return link, nil
+		}
+	}
+
 	link, err := s.rep.FindById(id)
 	if err != nil {
 		return nil, apperrors.UnknownError{Err: err}
@@ -42,6 +58,8 @@ func (s *PgService) GetById(id string) (*Link, error) {
 		return nil, apperrors.NotFoundError{Message: "Link with given ID was not found."}
 	}
 
+	s.cache.Set(id, link, 0)
+
 	return link, nil
 }
 
@@ -55,6 +73,8 @@ func (s *PgService) GetAll(limit int, offset int) (Links, error) {
 }
 
 func (s *PgService) DeleteById(id string) error {
+	s.cache.Delete(id)
+
 	if err := s.rep.DeleteById(id); err != nil {
 		return apperrors.UnknownError{Err: err}
 	}