Feat(Initial): Initial Go codebase

backend/internal/common/database.go

@@ -0,0 +1,81 @@
+package common
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"time"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+	"gorm.io/gorm/logger"
+)
+
+type Database struct {
+	*gorm.DB
+}
+
+var DB *gorm.DB
+
+// Opening a database and save the reference to `Database` struct.
+func InitDB() *gorm.DB {
+	host := os.Getenv("DB_HOST")
+	user := os.Getenv("DB_USER")
+	pass := os.Getenv("DB_PASS")
+	dbName := os.Getenv("DB_NAME")
+	port := os.Getenv("DB_PORT")
+
+	var sslMode string
+	if os.Getenv("DB_SSL") == "TRUE" {
+		sslMode = "enable"
+	} else {
+		sslMode = "disable"
+	}
+
+	// DB Logger config
+	newLogger := logger.New(
+		log.New(os.Stdout, "\r\n", log.LstdFlags), // io writer
+		logger.Config{
+			SlowThreshold:             time.Second,   // Slow SQL threshold
+			LogLevel:                  logger.Silent, // Log level
+			IgnoreRecordNotFoundError: true,          // Ignore ErrRecordNotFound error for logger
+			Colorful:                  true,          // Disable color
+		},
+	)
+
+	dsn := fmt.Sprintf("host=%s user=%s password=%s dbname=%s port=%s sslmode=%s TimeZone=Asia/Singapore", host, user, pass, dbName, port, sslMode)
+	db, err := gorm.Open(postgres.Open(dsn), &gorm.Config{
+		Logger: newLogger,
+	})
+	if err != nil {
+		fmt.Println("db err: (Init) ", err)
+	}
+	DB = db
+	return DB
+}
+
+// This function will create a temporarily database for running testing cases
+func TestDBInit() *gorm.DB {
+	testSQLDB, mock, err := sqlmock.New()
+	if err != nil {
+		panic(err)
+	}
+
+	testDB, err := gorm.Open(postgres.New(postgres.Config{
+		Conn: testSQLDB,
+	}), &gorm.Config{})
+
+	if err != nil {
+		fmt.Println("db err: (TestDBInit) ", err)
+	}
+
+	DB = testDB
+	_ = mock
+	return DB
+}
+
+// Using this function to get a connection, you can create your connection pool here.
+func GetDB() *gorm.DB {
+	return DB
+}

backend/internal/common/errresponse.go

@@ -0,0 +1,56 @@
+package common
+
+import (
+	"net/http"
+
+	"github.com/go-chi/render"
+)
+
+type ErrResponse struct {
+	Err            error `json:"-"` // low-level runtime error
+	HTTPStatusCode int   `json:"-"` // http response status code
+
+	StatusText string `json:"status"`          // user-level status message
+	AppCode    int64  `json:"code,omitempty"`  // application-specific error code
+	ErrorText  string `json:"error,omitempty"` // application-level error message, for debugging
+}
+
+func (e *ErrResponse) Render(w http.ResponseWriter, r *http.Request) error {
+	render.Status(r, e.HTTPStatusCode)
+	return nil
+}
+
+func ErrInvalidRequest(err error) render.Renderer {
+	return &ErrResponse{
+		Err:            err,
+		HTTPStatusCode: 400,
+		StatusText:     "Invalid request.",
+		ErrorText:      err.Error(),
+	}
+}
+
+func ErrValidationError(err error) render.Renderer {
+	return &ErrResponse{
+		Err:            err,
+		HTTPStatusCode: 422,
+		StatusText:     "Validation error.",
+		ErrorText:      err.Error(),
+	}
+}
+
+func ErrInternalError(err error) render.Renderer {
+	return &ErrResponse{
+		Err:            err,
+		HTTPStatusCode: 500,
+		StatusText:     "Invalid request.",
+		ErrorText:      err.Error(),
+	}
+}
+
+func ErrNotFound(err error) render.Renderer {
+	return &ErrResponse{
+		HTTPStatusCode: 404,
+		StatusText:     "Resource not found.",
+		ErrorText:      err.Error(),
+	}
+}

backend/internal/common/textresponse.go

@@ -0,0 +1,24 @@
+package common
+
+import (
+	"net/http"
+
+	"github.com/go-chi/render"
+)
+
+type TextResponse struct {
+	Status string `json:"status"` // user-level status message
+	Text   string `json:"text"`   // application-specific error code
+}
+
+func (e *TextResponse) Render(w http.ResponseWriter, r *http.Request) error {
+	render.Status(r, http.StatusOK)
+	return nil
+}
+
+func NewGenericTextResponse(status string, text string) render.Renderer {
+	return &TextResponse{
+		Status: status,
+		Text:   text,
+	}
+}