Normalize JSON

normalize_json.go

package main

import (
	"encoding/json"
	"fmt"
	"io"
	"os"
	"sort"
)

// normalizeJSON recursively processes JSON data and returns a normalized version
func normalizeJSON(data interface{}) interface{} {
	switch v := data.(type) {
	case map[string]interface{}:
		// For objects, sort keys and normalize values
		normalized := make(map[string]interface{})
		keys := make([]string, 0, len(v))

		// Collect all keys
		for k := range v {
			keys = append(keys, k)
		}

		// Sort keys
		sort.Strings(keys)

		// Process each value recursively
		for _, k := range keys {
			normalized[k] = normalizeJSON(v[k])
		}
		return normalized

	case []interface{}:
		// For arrays, normalize each element
		normalized := make([]interface{}, len(v))
		for i, val := range v {
			normalized[i] = normalizeJSON(val)
		}
		return normalized

	default:
		// For primitive types, return as-is
		return v
	}
}

func main() {
	// Read JSON from stdin
	input, err := io.ReadAll(os.Stdin)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error reading input: %v\n", err)
		os.Exit(1)
	}

	// Parse JSON
	var data interface{}
	if err := json.Unmarshal(input, &data); err != nil {
		fmt.Fprintf(os.Stderr, "Error parsing JSON: %v\n", err)
		os.Exit(1)
	}

	// Normalize the JSON
	normalized := normalizeJSON(data)

	// Marshal back to JSON with indentation
	output, err := json.MarshalIndent(normalized, "", "  ")
	if err != nil {
		fmt.Fprintf(os.Stderr, "Error encoding JSON: %v\n", err)
		os.Exit(1)
	}

	// Write to stdout
	fmt.Println(string(output))
}