1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
package json
import (
"bytes"
"encoding/json"
"io"
"sort"
"strconv"
)
// A NodeType is the type of a Node.
type NodeType uint
const (
// DocumentNode the root of the document tree.
DocumentNode NodeType = iota
// ElementNode is an element.
ElementNode
// TextNode is the text content of a node.
TextNode
)
var NodeNames = map[NodeType]string{
DocumentNode: "DocumentNode",
ElementNode: "ElementNode",
TextNode: "TextNode",
}
// A Node consists of a NodeType and some Data (tag name for
// element nodes, content for text) and are part of a tree of Nodes.
type Node struct {
Parent, PrevSibling, NextSibling, FirstChild, LastChild *Node
Type NodeType
Data string
DataType string
level int
}
// ChildNodes gets all child nodes of the node.
func (n *Node) ChildNodes() []*Node {
var a []*Node
for nn := n.FirstChild; nn != nil; nn = nn.NextSibling {
a = append(a, nn)
}
return a
}
// InnerText gets the value of the node and all its child nodes.
func (n *Node) InnerText() string {
var output func(*bytes.Buffer, *Node)
output = func(buf *bytes.Buffer, n *Node) {
if n.Type == TextNode {
buf.WriteString(n.Data)
return
}
for child := n.FirstChild; child != nil; child = child.NextSibling {
output(buf, child)
}
}
var buf bytes.Buffer
output(&buf, n)
return buf.String()
}
// SelectElement finds the first of child elements with the
// specified name.
func (n *Node) SelectElement(name string) *Node {
for nn := n.FirstChild; nn != nil; nn = nn.NextSibling {
if nn.Data == name {
return nn
}
}
return nil
}
func parseValue(x interface{}, top *Node, level int) {
addNode := func(n *Node) {
if n.level == top.level {
top.NextSibling = n
n.PrevSibling = top
n.Parent = top.Parent
if top.Parent != nil {
top.Parent.LastChild = n
}
} else if n.level > top.level {
n.Parent = top
if top.FirstChild == nil {
top.FirstChild = n
top.LastChild = n
} else {
t := top.LastChild
t.NextSibling = n
n.PrevSibling = t
top.LastChild = n
}
}
}
// TODO check for null
switch v := x.(type) {
case []interface{}:
for _, vv := range v {
n := &Node{Type: ElementNode, level: level, DataType: "array"}
addNode(n)
parseValue(vv, n, level+1)
}
case map[string]interface{}:
// The Go’s map iteration order is random.
// (https://blog.golang.org/go-maps-in-action#Iteration-order)
var keys []string
for key := range v {
keys = append(keys, key)
}
sort.Strings(keys)
for _, key := range keys {
n := &Node{Data: key, Type: ElementNode, level: level, DataType: "object"}
addNode(n)
parseValue(v[key], n, level+1)
}
case string:
n := &Node{Data: v, Type: TextNode, level: level, DataType: "string"}
addNode(n)
case float64:
s := strconv.FormatFloat(v, 'f', -1, 64)
n := &Node{Data: s, Type: TextNode, level: level, DataType: "number"}
addNode(n)
case bool:
s := strconv.FormatBool(v)
n := &Node{Data: s, Type: TextNode, level: level, DataType: "boolean"}
addNode(n)
}
}
// Parse JSON document.
func Parse(r io.Reader) (*Node, error) {
var v interface{}
decoder := json.NewDecoder(r)
if err := decoder.Decode(&v); err != nil {
return nil, err
}
doc := &Node{Type: DocumentNode}
parseValue(v, doc, 1)
return doc, nil
}
|
