I have this post.go model
package models
type Post struct {
Id uint `json:"ID"`
Name string `json:"Name"`
Message string `gorm:"type:text; index" json:"Message"`
Status string `gorm:"type:varchar(255); index" json:"Status"`
Desc string `gorm:"type:text; index" json:"Desc"`
}
func (p *Post) BeforeCreate() (err error) {
p.Status = "todo"
return nil
}
I need when I create any record by default put the status into the todo value
in my controller:
config.DB.Model(&models.Post{}).Create(&posts)
The result is I got a null value in status in the database
BeforeCreate interface signature is incorrect it should be BeforeCreate(*gorm.DB) error
func (p *Post) BeforeCreate(tx *gorm.DB) (err error) {
p.Status = "todo"
return nil
}
Another way would be to add default-values to the post struct
type Post struct {
Id uint `json:"ID"`
Name string `json:"Name"`
Message string `gorm:"type:text; index" json:"Message"`
Status string `gorm:"type:varchar(255); index; default: todo" json:"Status"`
Desc string `gorm:"type:text; index" json:"Desc"`
}
Output:
db.Create(&Post{}) // INSERT INTO `posts` (`name`,`message`,`status`,`desc`) VALUES ("","","todo","") RETURNING `id`
Related
I have the following test function.
func (s *Suite) Test_delete() {
var (
id = uuid.New()
name = "test"
quantity = 2
)
s.mock.ExpectQuery(regexp.QuoteMeta(
`SELECT * FROM "items" WHERE code = $1 AND "items"."deleted_at" IS NULL`,
)).
WithArgs(id).
WillReturnRows(sqlmock.NewRows([]string{"code", "name", "quantity"}).
AddRow(id, name, quantity))
err := s.repository.DeleteItem(id.String())
require.NoError(s.T(), err)
}
Now the problem is trying to scan the id variable into the row for the column code. In my Product struct, I have code defined as follows.
type Item struct {
Code uuid.UUID `gorm:"type:uuid;primaryKey" json:"code"`
Name string `json:"name" validate:"required"`
Quantity int `json:"qty" validate:"required,min=0"`
DeletedAt gorm.DeletedAt `json:"-" gorm:"index"`
}
func (i *Item) BeforeCreate(tx *gorm.DB) (err error) {
if i.Code == uuid.Nil {
i.Code = uuid.New()
}
return
}
Now the problem is when I try to run the test function, it is somehow unable to scan uuid.UUID into UUID even though they are both the same types. Here is the exact error message.
msql: Scan error on column index 0, name "code": Scan: unable to scan type uuid.UUID into UUID
Could someone help me on this part?
Read this. I assume there is type casting error. Changing WillReturnRows(sqlmock.NewRows([]string{"code", "name", "quantity"}).AddRow(id, name, quantity))->WillReturnRows(sqlmock.NewRows([]string{"code", "name", "quantity"}).AddRow(id.String(), name, quantity)) may help.
I have two models and their BeforeSave() Hooks
type Store struct {
ID int `json:"id"`
Name string `json:"name"`
Products []*Product `json:"products"`
}
type Product struct {
ID int `json:"id"`
Name string `json:"name"`
}
func (s *Store) BeforeSave(db *gorm.DB) error {
.....
return nil
}
func (p *Product) BeforeSave(db *gorm.DB) error{
......
return nil
}
When I insert a new Store into database using Gorm db.Create(&product), both Hooks are invoked. Is there any way to skip hook of Product (which means only invoke Store's BeforeSave())?
When I try to insert to a table with gorm which has one to many relationship, I get this error:
Error 1452: Cannot add or update a child row: a foreign key constraint fails (`Todo`.`todos`, CONSTRAINT `fk_users_todo_list` FOREIGN KEY (`fk_id`) REFERENCES `users` (`id`) ON DELETE SET NULL ON UPDATE CASCADE)....
These are my models:
type Base struct {
ID uint `gorm:"primaryKey"`
CreatedAt time.Time
UpdatedAt time.Time
DeletedAt *time.Time `gorm:"index"`
}
type User struct {
Base
FirstName string `form:"first_name" gorm:"type:varchar(20)"`
LastName string `form:"last_name" gorm:"type:varchar(20)"`
UserName string `form:"user_name" gorm:"unique;type:varchar(20)"`
Email string `form:"email" gorm:"type:varchar(100)"`
Password string `form:"password" gorm:"type:varchar(30)"`
Gender types.UserGender `form:"gender" gorm:"type:smallint"`
TodoList []Todo `gorm:"foreignKey:FkID;constraint:onDelete:SET NULL,onUpdate:CASCADE" json:"omitempty"`
}
type Todo struct {
Base
Name string
Description string
Status types.TaskStatus
FkID uint
}
And this is the function that I wrote:
func (d *DB) AddTODO(todo *models.Todo, userName string) error {
user := &models.User{UserName: userName}
err := d.db.Model(&user).Where("user_name = ?", userName).Association("TodoList").
Append([]models.Todo{*todo})
if err != nil {
return err
}
return nil
}
I'm using MariaDB.
It want user from gorm result. Change your method maybe like this:
// arg user is from gorm result somewhere
func (d *DB) AddTODO(user *models.User, todo *models.Todo) error {
return d.db.Model(user).Association("TodoList").Append([]models.Todo{*todo})
}
TodoList lack references keyword. It should be like this.
type User struct {
Base
FirstName string `form:"first_name" gorm:"type:varchar(20)"`
LastName string `form:"last_name" gorm:"type:varchar(20)"`
UserName string `form:"user_name" gorm:"unique;type:varchar(20)"`
Email string `form:"email" gorm:"type:varchar(100)"`
Password string `form:"password" gorm:"type:varchar(30)"`
Gender types.UserGender `form:"gender" gorm:"type:smallint"`
TodoList []Todo `gorm:"foreignKey:FkID;references:ID;constraint:onDelete:SET NULL,onUpdate:CASCADE" json:"omitempty"`
}
I have a query that fetches rows from jobs table and its author (each job has an author), but I want to select specific fields.
type User struct {
ID uint `gorm:"primarykey" json:"-"`
UUID uuid.UUID `gorm:"type:uuid not null" json:"-"`
Email string `gorm:"type:varchar(255); not null" json:"email"`
Name string `gorm:"type:varchar(255); not null" json:"name"`
AvatarURL string `gorm:"type:varchar(255); not null" json:"avatar_url"`
Provider string `gorm:"type:varchar(255); not null" json:"provider"`
ProviderID string `gorm:"type:varchar(255); not null" json:"-"`
Jobs []Job `json:"-"`
}
type Job struct {
ID uint `gorm:"primarykey" json:"id"`
Title string `gorm:"type:varchar(255); not null" json:"title"`
Content string `gorm:"not null" json:"content"`
UserID uint `json:"-"`
User User `json:"author"`
}
func (jobRepo repository) FindAll() ([]entity.Job, error) {
var jobs []entity.Job
if dbc := jobRepo.db.Preload("User", func(db *gorm.DB) *gorm.DB {
return db.Select("Name", "Email")
}).Find(&jobs); dbc.Error != nil {
return nil, dbc.Error
}
return jobs, nil
}
The custom preload does not behave as desired. If I do not specify concrete fields, the query works and returns everything. Otherwise, If I specify some fields, it returns nothing.
This is because you didn't select primary key. Add "ID" into select clause:
func(db *gorm.DB) *gorm.DB {
return db.Select("ID", "Name", "Email")
}
Otherwise GORM doesn't know how to join users to jobs.
I'm using Go Buffalo's ORM Pop and want to store JSON in a field and be able to marshal it into a struct.
e.g.
schema.sql
CREATE TABLE tree (
id uuid PRIMARY KEY,
name text NOT NULL,
fruit json,
);
main.go
type Tree struct {
ID uuid.UUID `json:"id" db:"id"`
Name string `json:"name" db:"name"`
Fruit []Fruit `json:"fruit" db:"fruit"`
}
type Fruit struct {
ID int `json:"id"`
Name string `json:"name"`
}
I get the following error:
sql: converting argument $25 type: unsupported type []Fruit, a slice of struct
UPDATE
Based on feedback added the following methods:
type Fruits []Fruit
// Value implements the driver.Valuer interface
func (f Fruits) Value() (driver.Value, error) {
return json.Marshal(of)
}
// Scan implements the sql.Scanner interface
func (f * Fruits) Scan(value interface{}) error {
var data []byte
if b, ok := value.([]byte); !ok {
data = b
return errors.New("type assertion to []byte for Fruit failed")
}
return json.Unmarshal(data, &of)
}
Now receive the error:
Cannot fetch from database: unable to fetch records: sql: Scan error on column index 26, name "fruit": unexpected end of JSON input
Update 2
Updated Scan method to the following and fixed error:
// Scan implements the sql.Scanner interface
func (f * Fruits) Scan(value interface{}) error {
var data = []byte(value.([]uint8))
return json.Unmarshal(data, &of)
}
Based on the help provided by #mkopriva
You need to provide Value and Scan methods for your struct
// Tree tall tree with many fruit
type Tree struct {
ID uuid.UUID `json:"id" db:"id"`
Name string `json:"name" db:"name"`
Fruit []Fruit `json:"fruit" db:"fruit"`
}
// Fruit fruit found on a tree
type Fruit struct {
ID int `json:"id"`
Name string `json:"name"`
}
// Creates a splice of Fruit
type Fruits []Fruit
// Value implements the driver.Valuer interface
func (f Fruits) Value() (driver.Value, error) {
return json.Marshal(of)
}
// Scan implements the sql.Scanner interface
func (f * Fruits) Scan(value interface{}) error {
var data = []byte(value.([]uint8))
return json.Unmarshal(data, &f)
}