package models import ( "errors" "fmt" "reflect" "strings" "time" "github.com/astaxie/beego/orm" ) type Post struct { Id int `orm:"column(id);pk"` Name string `orm:"column(name);null"` Data string `orm:"column(data)"` Meta string `orm:"column(meta)"` Created time.Time `orm:"column(created);type(timestamp with time zone);auto_now_add"` Modified time.Time `orm:"column(modified);type(timestamp with time zone);auto_now_add"` } func (t *Post) TableName() string { return "post" } func init() { orm.RegisterModel(new(Post)) } // AddPost insert a new Post into database and returns // last inserted Id on success. func AddPost(m *Post) (id int64, err error) { o := orm.NewOrm() id, err = o.Insert(m) return } // GetPostById retrieves Post by Id. Returns error if // Id doesn't exist func GetPostById(id int) (v *Post, err error) { o := orm.NewOrm() v = &Post{Id: id} if err = o.Read(v); err == nil { return v, nil } return nil, err } // GetAllPost retrieves all Post matches certain condition. Returns empty list if // no records exist func GetAllPost(query map[string]string, fields []string, sortby []string, order []string, offset int64, limit int64) (ml []interface{}, err error) { o := orm.NewOrm() qs := o.QueryTable(new(Post)) // query k=v for k, v := range query { // rewrite dot-notation to Object__Attribute k = strings.Replace(k, ".", "__", -1) if strings.Contains(k, "isnull") { qs = qs.Filter(k, (v == "true" || v == "1")) } else { qs = qs.Filter(k, v) } } // order by: var sortFields []string if len(sortby) != 0 { if len(sortby) == len(order) { // 1) for each sort field, there is an associated order for i, v := range sortby { orderby := "" if order[i] == "desc" { orderby = "-" + v } else if order[i] == "asc" { orderby = v } else { return nil, errors.New("Error: Invalid order. Must be either [asc|desc]") } sortFields = append(sortFields, orderby) } qs = qs.OrderBy(sortFields...) } else if len(sortby) != len(order) && len(order) == 1 { // 2) there is exactly one order, all the sorted fields will be sorted by this order for _, v := range sortby { orderby := "" if order[0] == "desc" { orderby = "-" + v } else if order[0] == "asc" { orderby = v } else { return nil, errors.New("Error: Invalid order. Must be either [asc|desc]") } sortFields = append(sortFields, orderby) } } else if len(sortby) != len(order) && len(order) != 1 { return nil, errors.New("Error: 'sortby', 'order' sizes mismatch or 'order' size is not 1") } } else { if len(order) != 0 { return nil, errors.New("Error: unused 'order' fields") } } var l []Post qs = qs.OrderBy(sortFields...) if _, err = qs.Limit(limit, offset).All(&l, fields...); err == nil { if len(fields) == 0 { for _, v := range l { ml = append(ml, v) } } else { // trim unused fields for _, v := range l { m := make(map[string]interface{}) val := reflect.ValueOf(v) for _, fname := range fields { m[fname] = val.FieldByName(fname).Interface() } ml = append(ml, m) } } return ml, nil } return nil, err } // UpdatePost updates Post by Id and returns error if // the record to be updated doesn't exist func UpdatePostById(m *Post) (err error) { o := orm.NewOrm() v := Post{Id: m.Id} // ascertain id exists in the database if err = o.Read(&v); err == nil { var num int64 if num, err = o.Update(m); err == nil { fmt.Println("Number of records updated in database:", num) } } return } // DeletePost deletes Post by Id and returns error if // the record to be deleted doesn't exist func DeletePost(id int) (err error) { o := orm.NewOrm() v := Post{Id: id} // ascertain id exists in the database if err = o.Read(&v); err == nil { var num int64 if num, err = o.Delete(&Post{Id: id}); err == nil { fmt.Println("Number of records deleted in database:", num) } } return }