ujson: examples

0_simplest.go

package main

import "fmt"
import "github.com/olvrng/ujson"

func main() {
	input0 := []byte(`true`)
	ujson.Walk(input0, func(level int, key, value []byte) bool {
		fmt.Printf("level=%v key=%s value=%s\n", level, key, value)
		return true
	})
	// output:
	//   level=0 key= value=true

	input1 := []byte(`{ "key": 42 }`)
	ujson.Walk(input1, func(level int, key, value []byte) bool {
		fmt.Printf("level=%v key=%s value=%s\n", level, key, value)
		return true
	})
	// output:
	//   level=0 key= value={
	//   level=1 key="key" value=42
	//   level=0 key= value=}

	input2 := []byte(`[ true ]`)
	ujson.Walk(input2, func(level int, key, value []byte) bool {
		fmt.Printf("level=%v key=%s value=%s\n", level, key, value)
		return true
	})
	// output:
	//   level=0 key= value=[
	//   level=1 key= value=true
	//   level=0 key= value=]
}

1_print_keys.go

package main	

import "fmt"	
import "github.com/olvrng/ujson"	

func main() {	
	input := []byte(`{	
    		"id": 12345,	
		"name": "foo",	
		"numbers": ["one", "two"],	
		"tags": {"color": "red", "priority": "high"},	
		"active": true	
	}`)	
	ujson.Walk(input, func(level int, key, value []byte) bool {	
		fmt.Printf("%2v% 12s : %s\n", level, key, value)	
		return true	
	})	
}

1_print_keys_output.txt

 0             : {
 1        "id" : 12345
 1      "name" : "foo"
 1   "numbers" : [
 2             : "one"
 2             : "two"
 1             : ]
 1      "tags" : {
 2     "color" : "red"
 2  "priority" : "high"
 1             : }
 1    "active" : true
 0             : }

2_reformat.go

package main

import "fmt"
import "github.com/olvrng/ujson"

func main() {
	input := []byte(`{"id":12345,"name":"foo","numbers":["one","two"],"tags":{"color":"red","priority":"high"},"active":true}`)

	b := make([]byte, 0, 1024)
	err := ujson.Walk(input, func(level int, key, value []byte) bool {
		if len(b) != 0 && ujson.ShouldAddComma(value, b[len(b)-1]) {
			b = append(b, ',')
		}
		b = append(b, '\n')
		for i := 0; i < level; i++ {
			b = append(b, '\t')
		}
		if len(key) > 0 {
			b = append(b, key...)
			b = append(b, `: `...)
		}
		b = append(b, value...)
		return true
	})
	if err != nil {
		panic(err)
	}
	fmt.Printf("%s\n", b)
}

2_reformat_output.txt

{
        "id": 12345,
        "name": "foo",
        "numbers": [
                "one",
                "two"
        ],
        "tags": {
                "color": "red",
                "priority": "high"
        },
        "active": true
}

3_blacklist.go

package main

import "bytes"
import "fmt"
import "github.com/olvrng/ujson"

func main() {
	input := []byte(`{
    		"id": 12345,
		"name": "foo",
		"numbers": ["one", "two"],
		"tags": {"color": "red", "priority": "high"},
		"active": true
	}`)

	blacklistFields := [][]byte{
		[]byte(`"numbers"`), // note the quotes
		[]byte(`"active"`),
	}
	b := make([]byte, 0, 1024)
	err := ujson.Walk(input, func(_ int, key, value []byte) bool {
		for _, blacklist := range blacklistFields {
			if bytes.Equal(key, blacklist) {
				// remove the key and value from the output
				return false
			}
		}

		// write to output
		if len(b) != 0 && ujson.ShouldAddComma(value, b[len(b)-1]) {
			b = append(b, ',')
		}
		if len(key) > 0 {
			b = append(b, key...)
			b = append(b, ':')
		}
		b = append(b, value...)
		return true
	})
	if err != nil {
		panic(err)
	}
	fmt.Printf("%s\n", b)
}

3_blacklist_input.json

{
  "responseHeader": {
    "status": 0,
    "QTime": 0,
    "params": {
      "q": "solo",
      "wt": "json"
    }
  },
  "response": {
    "numFound": 2,
    "start": 0,
    "docs": [
      { "name": "foo" },
      { "name": "bar" }
    ]
  }
}

3_blacklist_output.txt

{"id":12345,"name":"foo","tags":{"color":"red","priority":"high"}}

4_wrap_int64.go

package main

import "bytes"
import "fmt"
import "github.com/olvrng/ujson"

func main() {
	input := []byte(`{"order_id": 12345678901234, "number": 12, "item_id": 12345678905678, "counting": [1,"2",3]}`)

	suffix := []byte(`_id"`) // note the ending quote "
	b := make([]byte, 0, 256)
	err := ujson.Walk(input, func(_ int, key, value []byte) bool {
		// Test for keys with suffix _id" and value is an int64 number. For valid json,
		// values will never be empty, so we can safely test only the first byte.
		shouldWrap := bytes.HasSuffix(key, suffix) && value[0] > '0' && value[0] <= '9'

		// transform the input, wrap values in double quotes
		if len(b) != 0 && ujson.ShouldAddComma(value, b[len(b)-1]) {
			b = append(b, ',')
		}
		if len(key) > 0 {
			b = append(b, key...)
			b = append(b, ':')
		}
		if shouldWrap {
			b = append(b, '"')
		}
		b = append(b, value...)
		if shouldWrap {
			b = append(b, '"')
		}
		return true
	})
	if err != nil {
		panic(err)
	}
	fmt.Printf("%s\n", b)
}

4_wrap_int64_output.txt

{"order_id":"12345678901234","number":12,"item_id":"12345678905678","counting":[1,"2",3]}