Golang Benchmark for Slice Map Decoder of DynamoDB result on github.com/evalphobia/aws-sdk-go-wrapper

benchmark_test.go

package dynamodb

import (
	"fmt"
	"testing"

	"github.com/aws/aws-sdk-go/service/dynamodb/dynamodbattribute"
)

func BenchmarkToSliceMap_old(b *testing.B) {
	res, err := getQueryResultForBenchmark()
	if err != nil {
		b.Errorf("%s", err.Error())
		return
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		v := res.ToSliceMap_old()
		if len(v) == 0 {
			b.Errorf("Error on ToSliceMap_old")
		}
	}
}

func BenchmarkToSliceMap_dynamodbattribute(b *testing.B) {
	res, err := getQueryResultForBenchmark()
	if err != nil {
		b.Errorf("%s", err.Error())
		return
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		v := res.ToSliceMap_dynamodbattribute()
		if len(v) == 0 {
			b.Errorf("Error on ToSliceMap_dynamodbattribute")
		}
	}
}

func BenchmarkToSliceMap_dynamodbattributeNumber(b *testing.B) {
	res, err := getQueryResultForBenchmark()
	if err != nil {
		b.Errorf("%s", err.Error())
		return
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		v := res.ToSliceMap_dynamodbattributeNumber()
		if len(v) == 0 {
			b.Errorf("Error on ToSliceMap_dynamodbattributeNumber")
		}
	}
}

func BenchmarkToSliceMap_new(b *testing.B) {
	res, err := getQueryResultForBenchmark()
	if err != nil {
		b.Errorf("%s", err.Error())
		return
	}

	b.ResetTimer()
	for i := 0; i < b.N; i++ {
		v := res.ToSliceMap_new()
		if len(v) == 0 {
			b.Errorf("Error on ToSliceMap_new")
		}
	}
}

func getQueryResultForBenchmark() (QueryResult, error) {
	res := QueryResult{}
	for _, v := range testData {
		attrs, err := dynamodbattribute.MarshalMap(&v)
		if err != nil {
			return res, fmt.Errorf("Initializing error on dynamodbattribute.MarshalMap: [%v]", err)
		}
		res.Items = append(res.Items, attrs)
	}
	return res, nil
}

var testData = []map[string]interface{}{
	{
		"A_int":    100,
		"B_int64":  int64(100),
		"C_string": "abcdefgf1",
		"D_bool":   true,
	},
	{
		"A_int":    200,
		"B_int64":  int64(200),
		"C_string": "abcdefgf2",
		"D_bool":   true,
	},
	{
		"A_int":    300,
		"B_int64":  int64(300),
		"C_string": "abcdefgf3",
		"D_bool":   true,
	},
	{
		"A_int":    400,
		"B_int64":  int64(400),
		"C_string": "abcdefgf4",
		"D_bool":   true,
	},
	{
		"A_int":    105,
		"B_int64":  int64(105),
		"C_string": "abcdefgf5",
		"D_bool":   true,
	},
}

query_result.go

package dynamodb

import (
	SDK "github.com/aws/aws-sdk-go/service/dynamodb"
	"github.com/aws/aws-sdk-go/service/dynamodb/dynamodbattribute"
)

func (r QueryResult) ToSliceMap_old() []map[string]interface{} {
	m := make([]map[string]interface{}, len(r.Items))
	for i, item := range r.Items {
		m[i] = UnmarshalAttributeValue(item)
	}
	return m
}

func (r QueryResult) ToSliceMap_new() []map[string]interface{} {
	m := make([]map[string]interface{}, len(r.Items))
	for i, item := range r.Items {
		var v customeValues
		err := dynamodbattribute.UnmarshalMap(item, &v)
		if err != nil {
			continue
		}
		m[i] = v.ToMap()
	}
	return m
}

type customeValues map[string]customeValue

func (v customeValues) ToMap() map[string]interface{} {
	m := make(map[string]interface{}, len(v))
	for key, val := range v {
		m[key] = val.Value
	}
	return m
}

func (r QueryResult) ToSliceMap_dynamodbattribute() []map[string]interface{} {
	m := make([]map[string]interface{}, len(r.Items))
	for i, item := range r.Items {
		var v map[string]interface{}
		err := dynamodbattribute.UnmarshalMap(item, &v)
		if err != nil {
			continue
		}
		m[i] = v
	}
	return m
}

func (r QueryResult) ToSliceMap_dynamodbattributeNumber() []map[string]interface{} {
	decoder := dynamodbattribute.NewDecoder(func(d *dynamodbattribute.Decoder) {
		d.UseNumber = true
	})

	m := make([]map[string]interface{}, len(r.Items))
	for i, item := range r.Items {
		var v map[string]interface{}
		err := decoder.Decode(&SDK.AttributeValue{M: item}, &v)
		if err != nil {
			continue
		}
		m[i] = v
	}
	return m
}

$ go test  -bench . -benchmem

goos: darwin
goarch: amd64
pkg: github.com/evalphobia/aws-sdk-go-wrapper/dynamodb

BenchmarkToSliceMap_old-8                       	  482179	      2505 ns/op	    1888 B/op	      26 allocs/op
BenchmarkToSliceMap_dynamodbattribute-8         	  111409	     10594 ns/op	    3688 B/op	      91 allocs/op
BenchmarkToSliceMap_dynamodbattributeNumber-8   	  121496	      9796 ns/op	    3640 B/op	      87 allocs/op
BenchmarkToSliceMap_new-8                       	   79880	     14838 ns/op	    5688 B/op	     111 allocs/op