Merge branch 'main' into change-/groups/{groupId}/users-route

model/stories.go

@@ -47,15 +47,20 @@ func GetStoryByID(db *gorm.DB, id int) (Story, error) {
 	return story, nil
 }
 
-func CreateStory(db *gorm.DB, story *Story) error {
-	err := db.
+func (s *Story) create(tx *gorm.DB) *gorm.DB {
+	return tx.
 		Preload(clause.Associations).
-		Create(story).
+		Create(s).
 		// Get associated Author. See
 		// https://github.com/go-gorm/gen/issues/618 on why
 		// a separate .First() is needed.
-		First(story).
-		Error
+		First(s)
+}
+
+func CreateStory(db *gorm.DB, story *Story) error {
+	err := db.Transaction(func(tx *gorm.DB) error {
+		return story.create(tx).Error
+	})
 	if err != nil {
 		return database.HandleDBError(err, "story")
 	}
@@ -109,14 +114,19 @@ func UpdateStory(db *gorm.DB, storyID int, newStory *Story) error {
 	return nil
 }
 
-func DeleteStory(db *gorm.DB, storyID int) (Story, error) {
-	var story Story
-	err := db.
+func (s *Story) delete(tx *gorm.DB, storyID uint) *gorm.DB {
+	return tx.
 		Preload(clause.Associations).
 		Where("id = ?", storyID).
-		First(&story). // store the value to be returned
-		Delete(&story).
-		Error
+		First(s). // store the value to be returned
+		Delete(s)
+}
+
+func DeleteStory(db *gorm.DB, storyID int) (Story, error) {
+	var story Story
+	err := db.Transaction(func(tx *gorm.DB) error {
+		return story.delete(tx, uint(storyID)).Error
+	})
 	if err != nil {
 		return story, database.HandleDBError(err, "story")
 	}

model/stories_test.go

@@ -9,6 +9,7 @@ import (
 	userenums "github.com/source-academy/stories-backend/internal/enums/users"
 	"github.com/source-academy/stories-backend/internal/testutils"
 	"github.com/stretchr/testify/assert"
+	"gorm.io/gorm"
 )
 
 // FIXME: Coupling with the other operations in the users database
@@ -40,6 +41,25 @@ var (
 	}
 )
 
+func TestCreate(t *testing.T) {
+	t.Run("", func(t *testing.T) {
+		db, cleanUp := testutils.SetupDBConnection(t, dbConfig, migrationPath)
+		defer cleanUp(t)
+
+		// Any number is fine because the statement is not executed,
+		// thus removing the coupling with an actual author having to be
+		// created prior.
+		story := &Story{
+			AuthorID: 1,
+			Content:  "The quick brown test content 5678.",
+		}
+		sql := db.ToSQL(func(tx *gorm.DB) *gorm.DB {
+			return story.create(tx)
+		})
+		assert.Contains(t, sql, "The quick brown test content 5678.", "Should contain the story content")
+	})
+}
+
 func TestCreateStory(t *testing.T) {
 	t.Run("should increase the total story count", func(t *testing.T) {
 		db, cleanUp := testutils.SetupDBConnection(t, dbConfig, migrationPath)
@@ -221,8 +241,8 @@ func TestStoryDB(t *testing.T) {
 		}
 		_ = CreateGroup(db, &group)
 
-		err := db.Exec(`INSERT INTO "stories" 
-		("created_at","updated_at","deleted_at","author_id","group_id","title","content","pin_order") 
+		err := db.Exec(`INSERT INTO "stories"
+		("created_at","updated_at","deleted_at","author_id","group_id","title","content","pin_order")
 		VALUES ('2023-08-08 22:17:28.085','2023-08-08 22:17:28.085',NULL,NULL,NULL,'','# Hi, This is a test story.',NULL)`).
 			Error
 		var pgerr *pgconn.PgError

model/users.go

@@ -31,16 +31,24 @@ func GetUserByID(db *gorm.DB, id int) (User, error) {
 	return user, err
 }
 
-func CreateUser(db *gorm.DB, user *User) error {
+func (u *User) create(tx *gorm.DB) *gorm.DB {
 	// TODO: If user already exists, but is soft-deleted, undelete the user
-	err := db.Create(user).Error
+	return tx.Create(u)
+}
+
+func CreateUser(db *gorm.DB, user *User) error {
+	err := db.Transaction(func(tx *gorm.DB) error {
+		return user.create(tx).Error
+	})
 	if err != nil {
 		return database.HandleDBError(err, "user")
 	}
 	return nil
 }
 
 func CreateUsers(db *gorm.DB, users *[]*User) (int64, error) {
+	// TODO: Use users.create() instead
+	// Blocked by `RowsAffected` not being accessible.
 	tx := db.Create(users)
 	rowCount := tx.RowsAffected
 	if err := tx.Error; err != nil {
@@ -49,21 +57,19 @@ func CreateUsers(db *gorm.DB, users *[]*User) (int64, error) {
 	return rowCount, nil
 }
 
-func DeleteUser(db *gorm.DB, userID int) (User, error) {
-	var user User
-	err := db.
-		Model(&user).
+func (u *User) delete(tx *gorm.DB, userID uint) *gorm.DB {
+	return tx.
+		Model(u).
 		Where("id = ?", userID).
-		First(&user).
-		Error
-	if err != nil {
-		return user, database.HandleDBError(err, "user")
-	}
+		First(u). // store the value to be returned
+		Delete(u)
+}
 
-	err = db.
-		Model(&user).
-		Delete(&user).
-		Error
+func DeleteUser(db *gorm.DB, userID int) (User, error) {
+	var user User
+	err := db.Transaction(func(tx *gorm.DB) error {
+		return user.delete(tx, uint(userID)).Error
+	})
 	if err != nil {
 		return user, database.HandleDBError(err, "user")
 	}

scripts/create_db.go

@@ -4,101 +4,47 @@ import (
 	"errors"
 	"fmt"
 
-	"github.com/source-academy/stories-backend/internal/config"
-	"gorm.io/driver/postgres"
 	"gorm.io/gorm"
 )
 
-func connectAnonDB(conf config.DatabaseConfig) (*gorm.DB, error) {
-	conf.DatabaseName = ""
-	dsn := conf.ToDataSourceName()
-	return connectDBHelper(dsn)
-}
-
-func connectDB(conf config.DatabaseConfig) (*gorm.DB, error) {
-	dsn := conf.ToDataSourceName()
-	return connectDBHelper(dsn)
-}
-
-func connectDBHelper(dsn string) (*gorm.DB, error) {
-	driver := postgres.Open(dsn)
-
-	db, err := gorm.Open(driver, &gorm.Config{})
-	if err != nil {
-		return nil, err
-	}
-
-	dbName, err := getConnectedDBName(db)
-	if err != nil {
-		panic(err)
-	}
-	fmt.Println(blueSandwich, "Connected to database", dbName+".")
-
-	return db, nil
-}
-
-func closeDBConnection(d *gorm.DB) {
-	db, err := d.DB()
-	if err != nil {
-		panic(err)
-	}
-
-	dbName, err := getConnectedDBName(d)
-	if err != nil {
-		panic(err)
-	}
-	fmt.Println(blueSandwich, "Closing connection with database", dbName+".")
-
-	if err := db.Close(); err != nil {
-		panic(err)
-	}
-}
-
-func createDB(db *gorm.DB, dbconf *config.DatabaseConfig) error {
-	if dbconf.DatabaseName == "" {
+func createDB(db *gorm.DB, dbName string) error {
+	if dbName == "" {
 		return errors.New("Failed to create database: no database name provided.")
 	}
 
 	// check if db exists
-	fmt.Println(yellowChevron, "Checking if database", dbconf.DatabaseName, "exists.")
-	result := db.Raw("SELECT * FROM pg_database WHERE datname = ?", dbconf.DatabaseName)
+	fmt.Println(yellowChevron, "Checking if database", dbName, "exists.")
+	result := db.Raw("SELECT * FROM pg_database WHERE datname = ?", dbName)
 	if result.Error != nil {
 		return result.Error
 	}
 
 	// if not exists create it
 	rec := make(map[string]interface{})
-	if result.Find(rec); len(rec) == 0 {
-		fmt.Println(yellowChevron, "Database", dbconf.DatabaseName, "does not exist. Creating...")
-
-		create_command := fmt.Sprintf("CREATE DATABASE %s", dbconf.DatabaseName)
-		result := db.Exec(create_command)
-
-		if result.Error != nil {
-			return result.Error
-		}
+	if result.Find(rec); len(rec) != 0 {
+		fmt.Println(greenTick, "Database", dbName, "already exists.")
+		return nil
 	}
 
-	fmt.Println(yellowChevron, "Database", dbconf.DatabaseName, "exists.")
+	fmt.Println(yellowChevron, "Database", dbName, "does not exist. Creating...")
+	create_command := fmt.Sprintf("CREATE DATABASE %s", dbName)
+	err := db.Exec(create_command).Error
+	if err != nil {
+		return err
+	}
 
+	fmt.Println(greenTick, "Created database:", dbName)
 	return nil
 }
 
-func dropDB(db *gorm.DB, dbconf *config.DatabaseConfig) error {
-	drop_command := fmt.Sprintf("DROP DATABASE IF EXISTS %s;", dbconf.DatabaseName)
-	result := db.Exec(drop_command)
-	if result.Error != nil {
-		return result.Error
-	}
-
-	return nil
+func dropDB(db *gorm.DB, dbName string) error {
+	drop_command := fmt.Sprintf("DROP DATABASE IF EXISTS %s;", dbName)
+	err := db.Exec(drop_command).Error
+	return err
 }
 
-func getConnectedDBName(db *gorm.DB) (string, error) {
+func getDBName(db *gorm.DB) (string, error) {
 	var dbName string
-	result := db.Raw("SELECT current_database();").Scan(&dbName)
-	if result.Error != nil {
-		return "", result.Error
-	}
-	return dbName, nil
+	err := db.Raw("SELECT current_database();").Scan(&dbName).Error
+	return dbName, err
 }