This is a Go package to treat xml as a native database. You can access, modify or replace node
-
Declare Database.
var DB *xmlDB.Database = new(xmlDB.Database) -
Load Database.
xmlDB.Load_db(DB, "sample.html")
Content of sample.html
<!DOCTYPE html>
<html>
<head>
<title>This is document title</title>
</head>
<body style="123">
<h1>This is a heading</h1>
<p>Hello World!</p>
</body>
</html>
-
Identifying Nodes using Query.
identifiedNodes, _ := xmlDB.GetNode(DB, 0, "head*/title[This is document title]")- 'identifiedNodes' contains list of nodes ids(
<head>) identified under parent node with id '0' (<html> ..</html>). - '*' marks the node we require.
- [] encloses attribute or value of the node as additional search criteria.
- 'identifiedNodes' contains list of nodes ids(
-
Getting Content of identified nodes.
for _,node:=range identifiedNodes {
fmt.Printf("\n%s",xmlDB.GetNodeContents(DB, node))
}
Output
<head>
<title>This is document title</title>
</head>
- Getting Value of identified nodes.
identifiedNodes, _ := xmlDB.GetNode(DB, 0, "head/title*")
for _,node:=range identifiedNodes {
fmt.Printf("\n%s",xmlDB.GetNodeValue(DB, node))
}
Output
This is document title
-
Searching using attribute value.
identifiedNodes, _ = xmlDB.GetNode(DB, 0, "<x>*[style=\"123\"]/h1") -
Updating node
fmt.Printf("\n### Updating node ##\n")
identifiedNodes, _ = xmlDB.GetNode(DB, 0, "head/title")
for _, node := range identifiedNodes {
newnodes := xmlDB.ReplaceNode(DB, node, "<title>test</title>")
fmt.Printf("After updation\n")
fmt.Printf("old node value- %s", xmlDB.GetNodeValue(DB, node)) //no output, existing id is removed and new id added
fmt.Printf("\nnew node value- %s", xmlDB.GetNodeValue(DB, newnodes[0]))
}
fmt.Printf("\n### Updating node attribute##\n")
identifiedNodes, _ = xmlDB.GetNode(DB, 0, "<x>*[style=\"123\"]/h1")
for _, node := range identifiedNodes {
fmt.Printf("\n%s", xmlDB.GetNodeAttribute(DB, node, "style"))
xmlDB.UpdateAttributevalue(DB, node, "style", "test2")
fmt.Printf("\nafter updating Attribute-\n%s", xmlDB.GetNodeContents(DB, node))
xmlDB.UpdateAttributevalue(DB, node, "label", "value")
fmt.Printf("\nafter adding Attribute-\n%s", xmlDB.GetNodeContents(DB, node))
}
Output
### Updating node ##
After updation
Warning :node doesnot exist
old node value-
new node value- test
### Updating node attribute##
123
after updating Attribute-
<body style="test2">
<h1>This is a heading with style</h1>
<p>Hello World!</p>
</body>
after adding Attribute-
<body style="test2" label="value">
<h1>This is a heading with style</h1>
<p>Hello World!</p>
</body>
-
Recursive search.
identifiedNodes, _ = xmlDB.GetNode(DB, 0, "../h1")
Also see Example :"https://github.com/LIJUCHACKO/ods2csv". I have used this library to parse ods xml content.
<!DOCTYPE html>
<html>
<head><title>This is document title</title></head>
<body style="123">
<h1>This is a heading</h1>
<p>Hello World!</p>
</body>
</html>
| global_dbLines | global_ids | global_paths | global_values | global_attributes |
|---|---|---|---|---|
<!DOCTYPE html> |
-1 | |||
<head> |
0 | /head | ||
<title>This is document title</title> |
1 | /head/title | This is document title | |
<\head> |
2 | /head/~ | ||
<body style="123" font="arial"> |
3 | /body | style="123"|| font="arial" | |
<h1>This is a heading</h1> |
4 | /body/h1 | ||
<p>Hello World!</p> |
5 | /body/p | This is a heading | |
</body> |
6 | /body/~ | Hello World! | |
Note:- If a new node is inserted in between, global_id '7' will be assigned to it. global_id will be unique and will be retained till the node is deleted.
| index/global_id | nodeNoToLineno[index] |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 4 |
| index/global_id | Nodeendlookup[index] |
|---|---|
| 0 | 2 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 4 |
| 5 | 5 |
-Say the path is '/head/title' then hash is calculated for 'title'.
-Corresponding to the hash value a list of global_ids ,arranged in the increasing order of lineno, is stored.
| Hash no | global id list corresponding to the hash |
|---|---|
| 0 | |
| 1 | |
| 2 | [id1,id2,id3,id4] |
-Binary search is utilised to find ids, under a parent node, from this list.