func runFunc(c appengine.Context, w http.ResponseWriter, req *http.Request) {
defer req.Body.Close()
var inv invocation
if err := gob.NewDecoder(req.Body).Decode(&inv); err != nil {
c.Errorf("delay: failed decoding task payload: %v", err)
c.Warningf("delay: dropping task")
return
}
f := funcs[inv.Key]
if f == nil {
c.Errorf("delay: no func with key %q found", inv.Key)
c.Warningf("delay: dropping task")
return
}
ft := f.fv.Type()
in := []reflect.Value{reflect.ValueOf(c)}
for _, arg := range inv.Args {
var v reflect.Value
if arg != nil {
v = reflect.ValueOf(arg)
} else {
// Task was passed a nil argument, so we must construct
// the zero value for the argument here.
n := len(in) // we're constructing the nth argument
var at reflect.Type
if !ft.IsVariadic() || n < ft.NumIn()-1 {
at = ft.In(n)
} else {
at = ft.In(ft.NumIn() - 1).Elem()
}
v = reflect.Zero(at)
}
in = append(in, v)
}
out := f.fv.Call(in)
if n := ft.NumOut(); n > 0 && ft.Out(n-1) == errorType {
if errv := out[n-1]; !errv.IsNil() {
c.Errorf("delay: func failed (will retry): %v", errv.Interface())
w.WriteHeader(http.StatusInternalServerError)
return
}
}
}