Return Values

According func or method’s return values, returnHandle will automatically write content to ResponseWriter.

The return value could be below types or interfaces:

• string Will convert string to []byte and write to ResponseWriter

• []byte Write to ResponseWriter

• error If error is not nil, Write header 500 and the content is error.Error()

• AbortError if AbortError, Write header AbortError.Code and the content is AbortError.Error()

And if you have an anonymous tango.JSON or tango.XML, the return value could be:

• error If it’s Json, will reproduce {“err”: err.Error()}

• map If it’s Json, will reproduce json

• slice

• structs will reproduce json

For example, we will write a json response.

type Action struct {
    tango.JSON
}

var i int
func (Action) Get() interface{} {
   if i == 0 {
       i = i + 1
       return map[string]interface{}{"i":i}
   }
   return errors.New("could not visit")
}

func main() {
    t := tango.Classic()
    t.Any("/", new(Action))
    t.Run()
}

Of course you can also add HTTP status on return values. For example,

type Action struct {
    tango.JSON
}

var i int
func (Action) Get() (int, interface{}) {
   if i == 0 {
       i = i + 1
       return 200, map[string]interface{}{"i":i}
   }
   return 500, errors.New("could not visit")
}

func main() {
    t := tango.Classic()
    t.Any("/", new(Action))
    t.Run()
}