id  parentId    name		leaf
001	000 root	      	0
002 001 Shooping	    0
003	002	Housewares	0
004	003	Kitchen		1
005	003	Officer		1
006	002	Remodeling	0
007	006	Retile kitchen  1
008	006	Paint bedroom   1
009	008	Ceiling         1	
010	006	Other		1
011 001	Misc		1

{
"name": "root", 
"children": [
{
"name": "Shopping", 
"children": [
{
"name": "Housewares",
"children": [
{
"name": "Kitchen",
"leaf": "1"
},
{
"name": "Officer",
"leaf": "1"
}
]
},
{
"name": "Remodeling",
"children": [
{
"name": "Retile kitchen",
"leaf": "1"
},
{
"name": "Paint bedroom",
"children": [
{
"name": "Ceiling",
"leaf": "1"
}
]
},
{
"name": "Other",
"leaf": "1"
}
]
}
]
},
{
"name": "Misc",
"leaf": "1"
}
]
}

package main
import (
"fmt"
"encoding/json"
)
type Node struct {
ID string
Name    string `json:"name"`
Children []*Node  `json:"children"`
Leaf  string 	`json:"leaf"`
}
var rootNode *Node
func SaveTreetoJson(node []Node, parent string, depth int) {
for _, r := range node {
if r.parentID == parent {
for i := 0; i < depth; i++ {
AddtoJson(rootNode)//how to deal with the "AddtoJson" function  and the rootNode?
}
fmt.Print(r.Name, "\n\n")
SaveTreetoJson(node, r.ID, depth+1)
}
}
}
func main() {
data := []Node{
{"001","000","root","0"},
{"002","001","Shooping","0"},
{"003","002","Housewares","0"},
{"004","003","Kitchen","1"},
{"005","003","Officer","1"},
{"006","002","Remodeling","0"},
{"007","006","Retile kitchen","1"},
{"008","006","Paint bedroom","1"},
{"009","008","Ceiling","1"},	
{"010","006","Other","1"},
{"011","001","Misc","1"},
}
SaveTreetoJson(data, "root", 0)
bytes, _:= json.Marshal(rootNode)
fmt.Println(string(bytes)) 
}

type Node struct {
Id       string  `json:"-"`
ParentId string  `json:"-"`
Name     string  `json:"name"`
Leaf     string  `json:"leaf,omitempty"`
Children []*Node `json:"children,omitempty"`
}
func (this *Node) Size() int {
var size int = len(this.Children)
for _, c := range this.Children {
size += c.Size()
}
return size
}
func (this *Node) Add(nodes... *Node) bool {
var size = this.Size();
for _, n := range nodes {
if n.ParentId == this.Id {
this.Children = append(this.Children, n)
} else { 
for _, c := range this.Children {
if c.Add(n) {
break
}
}
}
}
return this.Size() == size + len(nodes)
}