godiff (Data structure diff for GoLang)

This library is compatible with Go 1.17+

Please refer to CHANGELOG.md if you encounter breaking changes.

• Motivation
• Usage
• Contribution
• License

Motivation

The goal of this library is to both produce diff and patch for arbitrary data structure in GoLang in performant manner

Other project for diffing golang structures and values:

• r3labs/diff

See 3rd party differ performance comparison.

• Benchmark

Usage

package godiff_test

import (
	"fmt"
	"github.com/viant/godiff"
	"log"
	"reflect"
	"testing"
)

type Flag struct {
	Value int
}
type Record struct {
	Id        int
	Name      string
	Dep       *Record
	Transient string `diff:"-"`
	Flags     []Flag
}

//ExampleNew shows basic differ usage
func ExampleNew() {

    record1 := &Record{
    Id:    1,
    Name:  "Rec1",
    Flags: []Flag{{Value: 3}, {Value: 15}},
    }
    
    record2 := &Record{
    Id:    2,
    Name:  "Rec1",
    Dep:   &Record{Id: 10},
    Flags: []Flag{{Value: 12}},
    }
    
    diff, err := godiff.New(reflect.TypeOf(record1), reflect.TypeOf(record2))
    if err != nil {
    log.Fatal(err)
    }
    changeLog := diff.Diff(record1, record2)
    fmt.Println(changeLog.String())
}

Supported tags:

• name - optional name in the change log
• indexBy - index elements before comparing
• sort - sort elements before comparing
• whitespace - remove specified whitespace chars when converting string to list or map
• pairSeparator - pair separator to convert string to a map comparison
• pairDelimiter - pair delimiter
• itemSeparator - item separator to convert string to a slice comparison
• '-' (ignore)

Work in progress tag:

• timeLayout
• precision

Config option

• WithTagName
• WithRegistry
• NullifyEmpty
• WithConfig

Diff option

• WithPresence
• WithShallow

Benchmark

GoDiff is around 5x faster than s3lab diff.

pkg: github.com/viant/godiff/bench
cpu: Intel(R) Core(TM) i9-9980HK CPU @ 2.40GHz
Benchmark_GoDiff
Benchmark_GoDiff-16       	 1432188	       815.9 ns/op	     768 B/op	      14 allocs/op
Benchmark_S3LabDiff
Benchmark_S3LabDiff-16    	  288633	      4531 ns/op	    2262 B/op	      42 allocs/op

Contributing to godiff

godiff is an open source project and contributors are welcome!

See TODO list

License

The source code is made available under the terms of the Apache License, Version 2, as stated in the file LICENSE.

Individual files may be made available under their own specific license, all compatible with Apache License, Version 2. Please see individual files for details.

Credits and Acknowledgements

Library Author: Adrian Witas