package data import ( "database/sql" "errors" ) type Command struct { ID int `json:"id"` Name string `json:"name"` Text string `json:"text"` Level int `json:"level"` } type CommandModel struct { DB *sql.DB } func (c CommandModel) Get(name string) (*Command, error) { query := ` SELECT id, name, text, level FROM commands WHERE name = $1` var command Command err := c.DB.QueryRow(query, name).Scan( &command.ID, &command.Name, &command.Text, &command.Level, ) if err != nil { switch { case errors.Is(err, sql.ErrNoRows): return nil, ErrRecordNotFound default: return nil, err } } return &command, nil } func (c CommandModel) SetLevel(name string, level int) error { query := ` UPDATE commands SET level = $2 WHERE name = $1` result, err := c.DB.Exec(query, name, level) if err != nil { return err } rowsAffected, err := result.RowsAffected() if err != nil { return err } if rowsAffected == 0 { return ErrRecordNotFound } return nil } func (c CommandModel) Insert(name, text string) error { perms := 0 query := ` INSERT into commands(name, text, level) VALUES ($1, $2, $3) ON CONFLICT (name) DO NOTHING RETURNING id; ` args := []interface{}{name, text, perms} result, err := c.DB.Exec(query, args...) if err != nil { return err } rowsAffected, err := result.RowsAffected() if err != nil { return err } if rowsAffected == 0 { return ErrCommandRecordAlreadyExists } return nil } func (c CommandModel) Delete(name string) error { // Prepare the statement. query := ` DELETE FROM commands WHERE name = $1` // Execute the query returning the number of affected rows. result, err := c.DB.Exec(query, name) if err != nil { return err } // Check how many rows were affected. rowsAffected, err := result.RowsAffected() if err != nil { return err } // We want atleast 1, if it is 0 the entry did not exist. if rowsAffected == 0 { return ErrRecordNotFound } return nil }