Hook
特性允许我们对特性的Model
绑定CURD
钩子处理。
相关定义
相关Hook
函数:
type (
HookFuncSelect func(ctx context.Context, in *HookSelectInput) (result Result, err error)
HookFuncInsert func(ctx context.Context, in *HookInsertInput) (result sql.Result, err error)
HookFuncUpdate func(ctx context.Context, in *HookUpdateInput) (result sql.Result, err error)
HookFuncDelete func(ctx context.Context, in *HookDeleteInput) (result sql.Result, err error)
)
// HookHandler manages all supported hook functions for Model.
type HookHandler struct {
Select HookFuncSelect
Insert HookFuncInsert
Update HookFuncUpdate
Delete HookFuncDelete
}
Hook
注册方法:
// Hook sets the hook functions for current model.
func (m *Model) Hook(hook HookHandler) *Model
使用示例
查询birth_day
字段时,同时计算出当前用户的年龄:
// Hook function definition.
var hook = gdb.HookHandler{
Select: func(ctx context.Context, in *gdb.HookSelectInput) (result gdb.Result, err error) {
result, err = in.Next(ctx)
if err != nil {
return
}
for i, record := range result {
if !record["birth_day"].IsEmpty() {
age := gtime.Now().Sub(record["birth_day"].GTime()).Hours() / 24 / 365
record["age"] = gvar.New(age)
}
result[i] = record
}
return
},
}
// It registers hook function, creates and returns a new `model`.
model := g.Model("user").Hook(hook)
// The hook function takes effect on each ORM operation when using the `model`.
all, err := model.Where("status", "online").OrderAsc(`id`).All()