package body type Message struct { MsgContent string `json:"msg_content"` Title string `json:"title,omitempty"` ContentType string `json:"content_type,omitempty"` Extras map[string]interface{} `json:"extras,omitempty"` } func (m *Message) SetMsgContent(c string) { m.MsgContent = c } func (m *Message) SetTitle(t string) { m.Title = t } func (m *Message) SetContentType(c string) { m.ContentType = c } func (m *Message) SetExtras(key string, value interface{}) { if m.Extras == nil { m.Extras = make(map[string]interface{}) } m.Extras[key] = value }