Instagram API for Go

package main

import (
    "encoding/json"
    "fmt"
    "net/http"
    "net/url"
)

const (
    apiKey  = "your_access_key"
    baseURL = "https://api.hikerapi.com"
)

type User struct {
    PK            int64  `json:"pk"`
    Username      string `json:"username"`
    FullName      string `json:"full_name"`
    FollowerCount int    `json:"follower_count"`
    MediaCount    int    `json:"media_count"`
}

func getUser(username string) (*User, error) {
    params := url.Values{"username": {username}}
    req, _ := http.NewRequest("GET",
        baseURL+"/v1/user/by/username?"+params.Encode(), nil)
    req.Header.Set("x-access-key", apiKey)

    resp, err := http.DefaultClient.Do(req)
    if err != nil {
        return nil, err
    }
    defer resp.Body.Close()

    var user User
    json.NewDecoder(resp.Body).Decode(&user)
    return &user, nil
}

func main() {
    user, _ := getUser("instagram")
    fmt.Printf("%s: %d followers\n", user.Username, user.FollowerCount)
}

func getUsers(usernames []string) []*User {
    ch := make(chan *User, len(usernames))
    for _, u := range usernames {
        go func(username string) {
            user, _ := getUser(username)
            ch <- user
        }(u)
    }
    users := make([]*User, 0, len(usernames))
    for range usernames {
        users = append(users, <-ch)
    }
    return users
}