jmespathvsmxj
JMESPath (pronounced “james path”) allows you to declaratively specify how to extract elements from a JSON document.
In web scraping, jmespath is a powerful tool for parsing and reshaping large JSON datasets. Jmespath is fast and easily extendible following it's own powerful query language.
For more see the Json parsing introduction section.
mxj is a Go library for working with JSON and XML data. It allows you to convert between JSON and XML, merge JSON and XML documents, and extract values from JSON and XML using a simple and intuitive API.
One of the main features of mxj is its ability to work with JSON and XML data in a struct-like manner, allowing you to access values using dot notation.
Example Use
import jmespath
data = {
"data": {
"info": {
"products": [
{"price": {"usd": 1}, "_type": "product", "id": "123"},
{"price": {"usd": 2}, "_type": "product", "id": "345"}
]
}
}
}
# easily reshape nested dataset to flat structure:
jmespath.search("data.info.products[*].{id:id, price:price.usd}", data)
[{'id': '123', 'price': 1}, {'id': '345', 'price': 2}]
package main
import (
"fmt"
"github.com/clbanning/mxj"
)
func main() {
// Parse the JSON string
jsonData := []byte(`
{
"name": "John Doe",
"age": 30,
"address": {
"street": "Main St",
"city": "Anytown",
"state": "CA",
"zip": "12345"
},
"phones": [
"555-555-5555",
"555-555-5556"
]
}
`)
mv, err := mxj.NewMapJson(jsonData)
if err != nil {
fmt.Println("Error:", err)
return
}
// Extract the name
name, _ := mv.ValueForPath("name")
fmt.Println("name:", name) // "John Doe"
// Extract the city
city, _ := mv.ValueForPath("address.city")
fmt.Println("city:", city) // "Anytown"
// Extract all phone numbers
phones, _ := mv.ValuesForPath("phones")
for _, phone := range phones {
fmt.Println("phone:", phone)
}
// "555-555-5555"
// "555-555-5556"
}