// Store a Model, and call SetKey after generating its key (if it doesn't
// have one already).
func PutModel(ctx appengine.Context, model models.Model) error {
modelKey, err := model.Key()
if err == models.NoKeyLoaded {
modelKey = datastore.NewIncompleteKey(ctx, model.Kind(), nil)
} else if err != nil {
panic(err)
}
key, err := datastore.Put(ctx, modelKey, model)
if err == nil {
model.SetKey(key)
}
return err
}
