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|
package json_test
import (
"context"
"fmt"
"log"
"github.com/goccy/go-json"
)
type User struct {
ID int64
Name string
Age int
Address UserAddressResolver
}
type UserAddress struct {
UserID int64
PostCode string
City string
Address1 string
Address2 string
}
type UserRepository struct {
uaRepo *UserAddressRepository
}
func NewUserRepository() *UserRepository {
return &UserRepository{
uaRepo: NewUserAddressRepository(),
}
}
type UserAddressRepository struct{}
func NewUserAddressRepository() *UserAddressRepository {
return &UserAddressRepository{}
}
type UserAddressResolver func(context.Context) (*UserAddress, error)
func (resolver UserAddressResolver) MarshalJSON(ctx context.Context) ([]byte, error) {
address, err := resolver(ctx)
if err != nil {
return nil, err
}
return json.MarshalContext(ctx, address)
}
func (r *UserRepository) FindByID(ctx context.Context, id int64) (*User, error) {
user := &User{ID: id, Name: "Ken", Age: 20}
// resolve relation from User to UserAddress
user.Address = func(ctx context.Context) (*UserAddress, error) {
return r.uaRepo.FindByUserID(ctx, user.ID)
}
return user, nil
}
func (*UserAddressRepository) FindByUserID(ctx context.Context, id int64) (*UserAddress, error) {
return &UserAddress{
UserID: id,
City: "A",
Address1: "foo",
Address2: "bar",
}, nil
}
func Example_fieldQuery() {
ctx := context.Background()
userRepo := NewUserRepository()
user, err := userRepo.FindByID(ctx, 1)
if err != nil {
log.Fatal(err)
}
query, err := json.BuildFieldQuery(
"Name",
"Age",
json.BuildSubFieldQuery("Address").Fields(
"City",
),
)
if err != nil {
log.Fatal(err)
}
ctx = json.SetFieldQueryToContext(ctx, query)
b, err := json.MarshalContext(ctx, user)
if err != nil {
log.Fatal(err)
}
fmt.Println(string(b))
// Output:
// {"Name":"Ken","Age":20,"Address":{"City":"A"}}
}
|
