Passing dynamic array struct to a function Golang - mongodb

Question

I want to create function that accept 'dynamic array struct' and use it to map a data from database *mgodb
type Cats struct {
Meow string
}
func getCatsPagination() {
mapStructResult("Animality","Cat_Col", Cats)
}
type Dogs struct {
Bark string
}
func getDogsPagination() {
mapStructResult("Animality","Dog_Col", Dogs)
}
func mapStructResult(db string, collection string, model interface{}) {
result := []model{} //gets an error here
err := con.Find(param).Limit(int(limit)).Skip(int(offset)).All(&result) // map any database result to 'any' struct provided
if err != nil {
log.Fatal(err)
}
}
and gets an error as "model is not a type", why is it?
any answer will be highly appreciated !

Answer 1

Pass the ready slice to the mapStructResult function.
type Cats struct {
Meow string
}
func getCatsPagination() {
cats := []Cats{}
mapStructResult("Animality", "Cat_Col", &cats)
}
type Dogs struct {
Bark string
}
func getDogsPagination() {
dogs := []Dogs{}
mapStructResult("Animality", "Dog_Col", &dogs)
}
func mapStructResult(db string, collection string, model interface{}) {
err := con.Find(param).Limit(int(limit)).Skip(int(offset)).All(result) // map any database result to 'any' struct provided
if err != nil {
log.Fatal(err)
}
}

Answer 2

First of all there is no term in go called dynamic struct. Struct fields are declared before using them and cannot be changed. We can use bson type to handle the data. Bson type is like map[string]interface{} used to save the data dynamically.
func mapStructResult(db string, collection string, model interface{}) {
var result []bson.M // bson.M works like map[string]interface{}
err := con.Find(param).Limit(int(limit)).Skip(int(offset)).All(&result) // map any database result to 'any' struct provided
if err != nil {
log.Fatal(err)
}
}
For more information on bson type. Look this godoc for BSON