From 8a234258269c4a06dc927088780fbb02dcb96e05 Mon Sep 17 00:00:00 2001
From: Andrey Chervyakov <cognioandrey@gmail.com>
Date: Tue, 16 Mar 2021 00:45:13 +0600
Subject: [PATCH] Add endpoint for updating link

---
 link/handlers.go   | 33 ++++++++++++++++++++++++++++-----
 link/repository.go | 33 +++++++++++++++++++++++++++++++++
 link/service.go    |  9 +++++++++
 3 files changed, 70 insertions(+), 5 deletions(-)

diff --git a/link/handlers.go b/link/handlers.go
index da5fc13..6892a35 100644
--- a/link/handlers.go
+++ b/link/handlers.go
@@ -5,6 +5,7 @@ import (
 	"github.com/jackc/pgx/v4/pgxpool"
 	"github.com/labstack/echo/v4"
 	"net/http"
+	"net/url"
 	"strconv"
 )
 
@@ -82,7 +83,7 @@ func allRetrievalHandler(c echo.Context, serv *PgService) error {
 	return c.JSON(http.StatusOK, models)
 }
 
-/*func updateHandler(c echo.Context, serv *PgService) error {
+func updateHandler(c echo.Context, serv *PgService) error {
 	linkId := c.Param("id")
 
 	var model UpdateModel
@@ -90,13 +91,35 @@ func allRetrievalHandler(c echo.Context, serv *PgService) error {
 		return echo.NewHTTPError(http.StatusBadRequest, "Invalid data format.")
 	}
 
-	l, err := serv.GetById(linkId)
+	updatingLink, err := serv.GetById(linkId)
 	if err != nil {
 		return err
 	}
 
+	hasChanges := false
+	switch {
+	case model.Name != "" && model.Name != updatingLink.Name:
+		updatingLink.Name = model.Name
+
+		hasChanges = true
+	case model.RedirectURL != "" && model.RedirectURL != updatingLink.RedirectURL.String():
+		if parsedUrl, err := url.Parse(model.RedirectURL); err != nil {
+			return echo.NewHTTPError(http.StatusBadRequest, "Invalid URL value.")
+		} else {
+			updatingLink.RedirectURL = *parsedUrl
+		}
+
+		hasChanges = true
+	}
+
+	if hasChanges {
+		if err = serv.Update(updatingLink); err != nil {
+			return err
+		}
+	}
+
 	return c.NoContent(http.StatusOK)
-}*/
+}
 
 func removalHandler(c echo.Context, serv *PgService) error {
 	linkId := c.Param("id")
@@ -126,9 +149,9 @@ func AddHandlers(s *echo.Echo, pool *pgxpool.Pool) {
 		return retrievalByIdHandler(ctx, &serv)
 	})
 
-	/*exactLinkGroup.PATCH("", func(ctx echo.Context) error {
+	exactLinkGroup.PATCH("", func(ctx echo.Context) error {
 		return updateHandler(ctx, &serv)
-	})*/
+	})
 
 	exactLinkGroup.DELETE("", func(ctx echo.Context) error {
 		return removalHandler(ctx, &serv)
diff --git a/link/repository.go b/link/repository.go
index f07792e..6ab2fb2 100644
--- a/link/repository.go
+++ b/link/repository.go
@@ -16,6 +16,7 @@ type Repository interface {
 	Save(link *Link) error
 	FindById(id string) (*Link, error)
 	FindAll(limit int, offset int) (Links, error)
+	Update(link *Link) error
 	DeleteById(id string) error
 }
 
@@ -135,6 +136,38 @@ func (r *PgRepository) FindAll(limit int, offset int) (Links, error) {
 	return links, nil
 }
 
+func (r *PgRepository) Update(link *Link) error {
+	if link.Id == "" {
+		return errors.New("link ID must not be empty")
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
+	defer cancel()
+
+	tx, err := r.pool.Begin(ctx)
+	if err != nil {
+		return err
+	}
+
+	sql := `
+		UPDATE links
+		SET name = $1, redirect_url = $2
+		WHERE id = $3
+	`
+
+	_, err = tx.Exec(ctx, sql, link.Name, link.RedirectURL.String(), link.Id)
+	if err != nil {
+		_ = tx.Rollback(ctx)
+		return err
+	}
+
+	if err = tx.Commit(ctx); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (r *PgRepository) DeleteById(id string) error {
 	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
 	defer cancel()
diff --git a/link/service.go b/link/service.go
index 3c89321..f6acee1 100644
--- a/link/service.go
+++ b/link/service.go
@@ -10,6 +10,7 @@ type Service interface {
 	Create(link *Link) error
 	GetById(id string) (*Link, error)
 	GetAll(limit int, offset int) (Links, error)
+	Update(data *Link) error
 	DeleteById(id string) error
 }
 
@@ -72,6 +73,14 @@ func (s *PgService) GetAll(limit int, offset int) (Links, error) {
 	return links, nil
 }
 
+func (s *PgService) Update(data *Link) error {
+	if err := s.rep.Update(data); err != nil {
+		return apperrors.UnknownError{Err: err}
+	}
+
+	return nil
+}
+
 func (s *PgService) DeleteById(id string) error {
 	s.cache.Delete(id)