convert query sql to gorm

README.md

@@ -204,4 +204,4 @@ Don't confuse the project level `/src` directory with the `/src` directory Go us
 
 ## Notes
 
-A more opinionated project template with sample/reusable configs, scripts and code is a WIP.
+A more opinionated project template with sample/reusable configs, scripts and code is a WIP.

go.mod

@@ -9,8 +9,24 @@ require (
 	gorm.io/gorm v1.25.1
 )
 
+require (
+	github.com/fsnotify/fsnotify v1.5.4 // indirect
+	github.com/hashicorp/hcl v1.0.0 // indirect
+	github.com/magiconair/properties v1.8.6 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/pelletier/go-toml v1.9.5 // indirect
+	github.com/spf13/afero v1.8.2 // indirect
+	github.com/spf13/cast v1.5.0 // indirect
+	github.com/spf13/jwalterweatherman v1.1.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/subosito/gotenv v1.4.1 // indirect
+	gopkg.in/ini.v1 v1.67.0 // indirect
+	gopkg.in/yaml.v2 v2.4.0 // indirect
+)
+
 require (
 	github.com/bytedance/sonic v1.8.0 // indirect
+	github.com/caarlos0/env v3.5.0+incompatible
 	github.com/cespare/xxhash/v2 v2.1.2 // indirect
 	github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
@@ -26,9 +42,10 @@ require (
 	github.com/klauspost/cpuid/v2 v2.0.9 // indirect
 	github.com/leodido/go-urn v1.2.1 // indirect
 	github.com/mattn/go-isatty v0.0.17 // indirect
-	github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pelletier/go-toml/v2 v2.0.6 // indirect
+	github.com/spf13/viper v1.13.0
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/ugorji/go/codec v1.2.9 // indirect
 	golang.org/x/arch v0.0.0-20210923205945-b76863e36670 // indirect
@@ -38,4 +55,5 @@ require (
 	golang.org/x/text v0.7.0 // indirect
 	google.golang.org/protobuf v1.28.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
+
 )

internal/sqlclient/sqlclient.go

@@ -0,0 +1,93 @@
+package sqlclient
+
+import (
+	"errors"
+	"fmt"
+	"gorm.io/driver/mysql"
+	"gorm.io/gorm"
+	"log"
+)
+
+const (
+	MYSQL = "mysql"
+)
+
+type ISqlClientConn interface {
+	GetDB() *gorm.DB
+	GetDriver() string
+}
+
+type SqlConfig struct {
+	Driver       string
+	Host         string
+	Port         int
+	Database     string
+	Username     string
+	Password     string
+	Timeout      int
+	DialTimeout  int
+	ReadTimeout  int
+	WriteTimeout int
+	PoolSize     int
+	MaxIdleConns int
+	MaxOpenConns int
+}
+
+type SqlClientConn struct {
+	SqlConfig
+	DB *gorm.DB
+}
+
+func NewSqlClient(config SqlConfig) ISqlClientConn {
+	client := &SqlClientConn{}
+	client.SqlConfig = config
+	if err := client.Connect(); err != nil {
+		log.Fatal(err)
+		return nil
+	}
+	//ping to check connection in gorm
+	sqlDB, err := client.DB.DB()
+	if err != nil {
+		log.Fatal(err)
+		return nil
+	}
+	if err := sqlDB.Ping(); err != nil {
+		log.Fatal(err)
+		return nil
+	}
+
+	return client
+}
+
+func (c *SqlClientConn) Connect() error {
+	switch c.Driver {
+	case MYSQL:
+		//username:password@protocol(address)/dbname?param=value
+		connectionString := fmt.Sprintf("%s:%s@tcp(%s:%d)/%s?parseTime=true&timeout=%ds", c.Username, c.Password, c.Host, c.Port, c.Database, c.Timeout)
+		db, err := gorm.Open(mysql.Open(connectionString), &gorm.Config{})
+		if err != nil {
+			log.Fatal(err)
+			return err
+		}
+		sqlDB, err := db.DB()
+		if err != nil {
+			log.Fatal(err)
+			return err
+		}
+		sqlDB.SetMaxIdleConns(c.MaxIdleConns)
+		sqlDB.SetMaxOpenConns(c.MaxOpenConns)
+		c.DB = db
+		return nil
+	default:
+		log.Fatal("driver is missing")
+		return errors.New("driver is missing")
+	}
+}
+
+func (c *SqlClientConn) GetDB() *gorm.DB {
+	return c.DB
+}
+
+func (c *SqlClientConn) GetDriver() string {
+	return c.Driver
+}

main.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"errors"
+	"github.com/EngineerProOrg/BE-K01/internal/sqlclient"
+	"github.com/EngineerProOrg/BE-K01/pkg/repository"
+	"github.com/caarlos0/env"
+	"github.com/spf13/viper"
+	"gorm.io/gorm"
+	"log"
+	"time"
+)
+
+type Config struct {
+	Dir string `env:"CONFIG_DIR" envDefault:"configs/config.json"`
+	DB  bool
+}
+
+var config Config
+var sqlClient sqlclient.ISqlClientConn
+
+func init() {
+	loc, err := time.LoadLocation("Asia/Ho_Chi_Minh")
+	if err != nil {
+		log.Fatal(err)
+	}
+	time.Local = loc
+
+	if err := env.Parse(&config); err != nil {
+		log.Fatal(err)
+	}
+	viper.SetConfigFile(config.Dir)
+	if err := viper.ReadInConfig(); err != nil {
+		log.Println(err.Error())
+		panic(err)
+	}
+
+	cfg := Config{
+		Dir: config.Dir,
+		DB:  viper.GetBool(`main.db`),
+	}
+
+	if cfg.DB {
+		sqlClientConfig := sqlclient.SqlConfig{
+			Driver:       "mysql",
+			Host:         viper.GetString(`db.host`),
+			Database:     viper.GetString(`db.database`),
+			Username:     viper.GetString(`db.username`),
+			Password:     viper.GetString(`db.password`),
+			Port:         viper.GetInt(`db.port`),
+			DialTimeout:  20,
+			ReadTimeout:  30,
+			WriteTimeout: 30,
+			Timeout:      30,
+			PoolSize:     10,
+			MaxIdleConns: 10,
+			MaxOpenConns: 10,
+		}
+		sqlClient = sqlclient.NewSqlClient(sqlClientConfig)
+		if sqlClient == nil {
+			panic(errors.New("sqlClient is nil"))
+		} else {
+			CreateOrUpdateGradeView(sqlClient.GetDB())
+		}
+	}
+
+}
+
+func CreateOrUpdateGradeView(db *gorm.DB) error {
+	query := `
+		CREATE OR REPLACE VIEW Grade AS
+		SELECT e.class_id, e.stud_id,
+		       CASE e.grade
+		           WHEN 'A' THEN 10
+		           WHEN 'B' THEN 8
+		           WHEN 'C' THEN 6
+		           WHEN 'D' THEN 4
+		           WHEN 'E' THEN 2
+		           WHEN 'F' THEN 0
+		           ELSE 0
+		       END
+		    AS Grade
+		FROM enrolls e
+	`
+	err := db.Exec(query).Error
+	return err
+}
+
+func main() {
+	stuRepo := repository.NewStudentRepository(sqlClient.GetDB())
+	courses, err := stuRepo.GetAvgGradeOfCourse()
+	if err != nil {
+		log.Fatal(err)
+	}
+	log.Println(courses)
+}

pkg/repository/course.go

@@ -0,0 +1,51 @@
+package repository
+
+import (
+	"github.com/EngineerProOrg/BE-K01/pkg/types"
+	"gorm.io/gorm"
+)
+
+type CourseRepository interface {
+	GetCourseWithProfessorTeaching() ([]string, error)
+	GetCourseWithStudentStudying() ([]string, error)
+}
+
+func NewCourseRepository(db *gorm.DB) CourseRepository {
+	return &CourseRepo{
+		db: db,
+	}
+}
+
+type CourseRepo struct {
+	db *gorm.DB
+}
+
+func (c CourseRepo) GetCourseWithStudentStudying() ([]string, error) {
+	var courses []string
+	c.db.Model(&types.Course{}).
+		Select("DISTINCT(course_name)").
+		Joins("JOIN Class ON Course.course_id = Class.course_id").
+		Joins("JOIN Enroll ON Class.class_id = Enroll.class_id").
+		Scan(&courses)
+	if err := c.db.Error; err != nil {
+		return nil, err
+	}
+	return courses, nil
+}
+
+type a struct {
+	s int
+}
+
+func (c CourseRepo) GetCourseWithProfessorTeaching() ([]string, error) {
+	var courses []string
+	c.db.Model(&types.Course{}).
+		Select("DISTINCT(course_name)").
+		Joins("JOIN classes ON courses.course_id = classes.course_id").
+		Scan(&courses)
+
+	if err := c.db.Error; err != nil {
+		return nil, err
+	}
+	return courses, nil
+}

pkg/repository/professor.go

@@ -0,0 +1,50 @@
+package repository
+
+import (
+	"github.com/EngineerProOrg/BE-K01/pkg/types"
+	"gorm.io/gorm"
+)
+
+type ProfessorRepository interface {
+	GetProfessorStudentClassNames() ([]QueryResult, error)
+}
+
+type ProfessorRepoDb struct {
+	db *gorm.DB
+}
+
+type ProfessorStudentClass struct {
+	ProfName    string `gorm:"column:professors Name"`
+	StudentName string `gorm:"column:Student Name"`
+	ClassName   string `gorm:"column:classes Name"`
+}
+
+type QueryResult struct {
+	ProfessorsName string `gorm:"column:Professor Name"`
+	StudentName    string `gorm:"column:Student Name"`
+	ClassName      string `gorm:"column:Class Name"`
+}
+
+func (p ProfessorRepoDb) GetProfessorStudentClassNames() ([]QueryResult, error) {
+	var result []QueryResult
+
+	p.db.Model(&types.Professor{}).
+		Select("CONCAT(professors.prof_fname, ' ', professors.prof_lname) AS 'Professor Name'",
+			"CONCAT(students.stud_fname, ' ', students.stud_lname) AS 'Student Name'",
+			"classes.class_name AS 'Class Name'").
+		Joins("JOIN classes ON professors.prof_id = classes.prof_id").
+		Joins("JOIN enrolls ON classes.class_id = enrolls.class_id").
+		Joins("JOIN students ON enrolls.stud_id = students.stud_id").
+		Scan(&result)
+
+	if err := p.db.Error; err != nil {
+		return nil, err
+	}
+	return result, nil
+}
+
+func NewProfessorRepository(db *gorm.DB) ProfessorRepository {
+	return &ProfessorRepoDb{
+		db: db,
+	}
+}