Marshal JSON field in database to struct using Pop - go

Question

I'm using Go Buffalo's ORM Pop and want to store JSON in a field and be able to marshal it into a struct.
e.g.
schema.sql
CREATE TABLE tree (
id uuid PRIMARY KEY,
name text NOT NULL,
fruit json,
);
main.go
type Tree struct {
ID uuid.UUID `json:"id" db:"id"`
Name string `json:"name" db:"name"`
Fruit []Fruit `json:"fruit" db:"fruit"`
}
type Fruit struct {
ID int `json:"id"`
Name string `json:"name"`
}
I get the following error:
sql: converting argument $25 type: unsupported type []Fruit, a slice of struct
UPDATE
Based on feedback added the following methods:
type Fruits []Fruit
// Value implements the driver.Valuer interface
func (f Fruits) Value() (driver.Value, error) {
return json.Marshal(of)
}
// Scan implements the sql.Scanner interface
func (f * Fruits) Scan(value interface{}) error {
var data []byte
if b, ok := value.([]byte); !ok {
data = b
return errors.New("type assertion to []byte for Fruit failed")
}
return json.Unmarshal(data, &of)
}
Now receive the error:
Cannot fetch from database: unable to fetch records: sql: Scan error on column index 26, name "fruit": unexpected end of JSON input
Update 2
Updated Scan method to the following and fixed error:
// Scan implements the sql.Scanner interface
func (f * Fruits) Scan(value interface{}) error {
var data = []byte(value.([]uint8))
return json.Unmarshal(data, &of)
}

Answer 1

Based on the help provided by #mkopriva
You need to provide Value and Scan methods for your struct
// Tree tall tree with many fruit
type Tree struct {
ID uuid.UUID `json:"id" db:"id"`
Name string `json:"name" db:"name"`
Fruit []Fruit `json:"fruit" db:"fruit"`
}
// Fruit fruit found on a tree
type Fruit struct {
ID int `json:"id"`
Name string `json:"name"`
}
// Creates a splice of Fruit
type Fruits []Fruit
// Value implements the driver.Valuer interface
func (f Fruits) Value() (driver.Value, error) {
return json.Marshal(of)
}
// Scan implements the sql.Scanner interface
func (f * Fruits) Scan(value interface{}) error {
var data = []byte(value.([]uint8))
return json.Unmarshal(data, &f)
}