Golang-从MySQL检索多个结果，然后将其显示为JSON

Recently, I'm learning about Go (Golang). I'm trying to make a simple web service using Martini and jwt-go. I didn't find any difficulty in retrieving a single row data and put in JSON as the response. But, when dealing with multiple-rows, it's a whole different story. Basically, I refer to the accepted answer here.

Here is the piece of my code:

m.Get("/users", func(params martini.Params, r render.Render) {
    db, err := sql.Open("mysql", "root:@/sirat_v2")
    if err != nil {
        panic(err.Error())
    }
    defer db.Close()

    rows, err := db.Query("SELECT user_id, nama FROM `users` WHERE password = ?", "asdfasdf")
    defer rows.Close()

    cols, err := rows.Columns()
    if err != nil {
        panic(err.Error())
    }

    partages := make([]*Partage, 0, 10)
    var user_id int
    var nama string
    for rows.Next() {
        err = rows.Scan(&user_id, &nama)
        if err != nil { /* error handling */
        }
        partages = append(partages, &Partage{user_id, nama})
    }
})

When trying to build, there's an error said that Partage is undefined.

The error showing up because you use struct Partage to create an object, but you haven't declared it.

type Partage struct {
    user_id string
    nama string
}

But how do I display the result as JSON response? I've tried r.JSON(200, partages) but the results aren't displayed

In martini you can use r.JSON() to print rows as JSON

m.Get("/users", func(params martini.Params, r render.Render) {
    // ... 

    r.JSON(200, map[string]interface{}{
        data: rows
    })
})