Products app

products/app/api/dto.go

@@ -0,0 +1,5 @@
+package api
+
+type PingDto struct {
+	Message string `json:"message"`
+}

products/app/api/helpers.go

@@ -0,0 +1,37 @@
+package api
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+)
+
+func isError(c *gin.Context, err error) bool {
+	if err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{
+			"details": err.Error(),
+		})
+		return true
+	}
+	return false
+}
+
+func raiseError(c *gin.Context, errCode int, message string) {
+	c.AbortWithStatusJSON(errCode, gin.H{
+		"details": message,
+	})
+}
+
+func raiseBadRequestError(c *gin.Context, message string) {
+	raiseError(c, http.StatusBadRequest, message)
+}
+
+func raiseNotFoundError(c *gin.Context, message string) {
+	raiseError(c, http.StatusNotFound, message)
+}
+
+func raiseInternalError(c *gin.Context, message string) {
+	c.AbortWithStatusJSON(http.StatusInternalServerError, gin.H{
+		"details": "Internal server error. We will we will fix it!",
+	})
+}

products/app/api/response.go

@@ -0,0 +1,7 @@
+package api
+
+import "products/app/db"
+
+type GetProductsResponse struct {
+	Products []db.Product `json:"products"`
+}

products/app/api/router.go

@@ -0,0 +1,75 @@
+package api
+
+import (
+	"fmt"
+	"net/http"
+	"products/app/db"
+	"strconv"
+
+	"github.com/gin-gonic/gin"
+	"gorm.io/gorm"
+)
+
+const HOST = "0.0.0.0"
+const PORT = 3000
+
+func handlePing(c *gin.Context) {
+	c.JSON(
+		http.StatusOK,
+		PingDto{
+			Message: "Pong!",
+		},
+	)
+}
+
+func handleGetProducts(dbConn *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		products := db.GetProducts(dbConn)
+
+		c.JSON(
+			http.StatusOK,
+			GetProductsResponse{
+				Products: *products,
+			},
+		)
+	}
+}
+
+func handleGetProduct(dbConn *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		productId, err := strconv.Atoi(c.Param("productId"))
+		if err != nil {
+			raiseBadRequestError(c, "Invalid productId parameter")
+			return
+		}
+
+		product, err := db.GetProduct(dbConn, productId)
+		if err != nil {
+			raiseNotFoundError(c, "Product not found")
+			return
+		}
+
+		c.JSON(
+			http.StatusOK,
+			product,
+		)
+	}
+}
+
+func initRouter(dbConn *gorm.DB) *gin.Engine {
+	gin.SetMode(gin.ReleaseMode)
+	router := gin.Default()
+
+	router.GET("/ping", handlePing)
+	router.GET("/", handleGetProducts(dbConn))
+	router.GET("/:productId", handleGetProduct(dbConn))
+
+	return router
+}
+
+func Serve(dbConn *gorm.DB) {
+	serverAddr := fmt.Sprintf("%s:%d", HOST, PORT)
+
+	router := initRouter(dbConn)
+	router.Run(serverAddr)
+}

products/app/cfg/config.go

@@ -0,0 +1,24 @@
+package cfg
+
+import (
+	"github.com/kelseyhightower/envconfig"
+)
+
+type configStruct struct {
+	DbHost     string `default:"localhost"`
+	DbPort     int    `default:"55432"`
+	DbName     string `default:"komponiranje"`
+	DbUser     string `default:"pero"`
+	DbPassword string `default:"pero.000"`
+}
+
+const ENV_PREFIX = ""
+
+var Config configStruct
+
+func init() {
+	err := envconfig.Process(ENV_PREFIX, &Config)
+	if err != nil {
+		panic(err)
+	}
+}

products/app/db/db.go

@@ -0,0 +1,30 @@
+package db
+
+import (
+	"fmt"
+	"products/app/cfg"
+
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	gormLogger "gorm.io/gorm/logger"
+)
+
+func ConnectDb() *gorm.DB {
+	var connectionString = fmt.Sprintf("postgres://%s:%s@%s:%d/%s?sslmode=disable",
+		cfg.Config.DbUser,
+		cfg.Config.DbPassword,
+		cfg.Config.DbHost,
+		cfg.Config.DbPort,
+		cfg.Config.DbName,
+	)
+
+	var err error
+	dbConn, err := gorm.Open(postgres.Open(connectionString), &gorm.Config{
+		Logger: gormLogger.Default.LogMode(gormLogger.Info),
+	})
+	if err != nil {
+		panic("Error connecting to database: " + err.Error())
+	}
+
+	return dbConn
+}

products/app/db/models.go

@@ -0,0 +1,12 @@
+package db
+
+type Product struct {
+	Id          int    `json:"id"`
+	Name        string `json:"name"`
+	Description string `json:"description"`
+	Image       string `json:"image"`
+}
+
+func (m *Product) TableName() string {
+	return "products"
+}

products/app/db/repository.go

@@ -0,0 +1,22 @@
+package db
+
+import "gorm.io/gorm"
+
+func GetProducts(dbConn *gorm.DB) *[]Product {
+	var products []Product
+
+	dbConn.Order("name").Find(&products)
+
+	return &products
+}
+
+func GetProduct(dbConn *gorm.DB, id int) (*Product, error) {
+	var product Product
+
+	result := dbConn.Order("name").Where("id = ?", id).First(&product)
+	if result.Error != nil {
+		return nil, result.Error
+	}
+
+	return &product, nil
+}

products/app/main.go

@@ -0,0 +1,11 @@
+package main
+
+import (
+	"products/app/api"
+	"products/app/db"
+)
+
+func main() {
+	dbConn := db.ConnectDb()
+	api.Serve(dbConn)
+}