Map JSON array value to struct specific variable - json

Question

Let's say I have this JSON structure:
{
"name":"repo",
"tags":["1.0","2.0","3.0"]
}
And I would like to map it to this Go struct:
type Repository struct {
Name string `json:"name"`
Tags []struct {
Tag string `json:"??"`
Sha256 string
}
}
How can I link the "tags" array JSON value to a struct field?
EDIT: The idea will be to access the tags array value like this
repository.Tags[0].Tag.

Answer 1

Implement json.Unmarshaler on a Tag type:
package main
import (
"encoding/json"
"log"
)
type Repository struct {
Name string
Tags []Tag
}
type Tag struct {
Tag string
Sha256 string
}
func (t *Tag) UnmarshalJSON(b []byte) error {
var s string
if err := json.Unmarshal(b, &s); err != nil {
return err
}
t.Tag = s
return nil
}
func main() {
b := []byte(`{ "name":"repo", "tags":["1.0","2.0","3.0"] }`)
var r Repository
err := json.Unmarshal(b, &r)
if err != nil {
log.Fatal(err)
}
log.Printf("%+v\n", r)
}
Try it on the playground: https://play.golang.org/p/ExwWhis0w0V
Marshaling back to JSON is left as an exercise for the reader.