Improve json unmarshalling performance

[camswords]

Summary

This pull request improves JSON unmarshalling performance by:

• Inlining the Chromium error response into the response struct so that json.Unmarshal only needs to be called once per message, and
• Replacing jsoniter with go-json as it is better maintained and seems to be more performant.

Benchmarks

The following test, benchmarked with the before and after versions of the code shows a 2.5x improvement on the sample data used. This is likely due to the reduced number of allocations.

goos: darwin
goarch: arm64
pkg: github.com/wirepair/gcd/v2
BenchmarkUnmarshalComputedStyleOld
BenchmarkUnmarshalComputedStyleOld-10    	   44449	     26598 ns/op	   10384 B/op	     551 allocs/op
BenchmarkUnmarshalComputedStyleNew
BenchmarkUnmarshalComputedStyleNew-10    	  111758	     10212 ns/op	    9760 B/op	     110 allocs/op

Test:

package gcd_test

import (
	"context"
	"github.com/wirepair/gcd/v2/gcdapi"
	"github.com/wirepair/gcd/v2/gcdmessage"
	"testing"
	"time"
)

func BenchmarkUnmarshalComputedStyleOld(b *testing.B) {
	var computedStyleJSON = []byte(`{"id":1015,"result":{"computedStyle":[{"name":"color","value":"rgb(255, 255, 255)"},{"name":"direction","value":"ltr"},{"name":"font-family","value":"\"Font Awesome 5 Free\""},{"name":"font-feature-settings","value":"normal"},{"name":"font-kerning","value":"auto"},{"name":"font-optical-sizing","value":"auto"},{"name":"font-palette","value":"normal"},{"name":"font-size","value":"22px"},{"name":"font-stretch","value":"100%"},{"name":"font-style","value":"normal"},{"name":"font-synthesis-small-caps","value":"auto"},{"name":"font-synthesis-style","value":"auto"},{"name":"font-synthesis-weight","value":"auto"},{"name":"font-variant-alternates","value":"normal"},{"name":"font-variant-caps","value":"normal"},{"name":"font-variant-east-asian","value":"normal"},{"name":"font-variant-ligatures","value":"normal"},{"name":"font-variant-numeric","value":"normal"},{"name":"font-variant-position","value":"normal"},{"name":"font-variation-settings","value":"normal"},{"name":"font-weight","value":"900"},{"name":"forced-color-adjust","value":"auto"},{"name":"text-orientation","value":"mixed"},{"name":"text-rendering","value":"auto"},{"name":"-webkit-font-smoothing","value":"antialiased"},{"name":"-webkit-locale","value":"\"en\""},{"name":"-webkit-text-orientation","value":"vertical-right"},{"name":"-webkit-writing-mode","value":"horizontal-tb"},{"name":"writing-mode","value":"horizontal-tb"},{"name":"zoom","value":"1"},{"name":"accent-color","value":"auto"},{"name":"align-content","value":"normal"},{"name":"align-items","value":"normal"},{"name":"align-self","value":"auto"},{"name":"alignment-baseline","value":"auto"},{"name":"all","value":""},{"name":"animation-composition","value":"replace"},{"name":"animation-delay","value":"0s"},{"name":"animation-direction","value":"normal"},{"name":"animation-duration","value":"0s"},{"name":"animation-fill-mode","value":"none"},{"name":"animation-iteration-count","value":"1"},{"name":"animation-name","value":"none"},{"name":"animation-play-state","value":"running"},{"name":"animation-range-end","value":"normal"},{"name":"animation-range-start","value":"normal"},{"name":"animation-timeline","value":"auto"},{"name":"animation-timing-function","value":"ease"},{"name":"app-region","value":"none"},{"name":"appearance","value":"none"},{"name":"aspect-ratio","value":"auto"},{"name":"backdrop-filter","value":"none"},{"name":"backface-visibility","value":"visible"},{"name":"background-attachment","value":"scroll"},{"name":"background-blend-mode","value":"normal"},{"name":"background-clip","value":"border-box"},{"name":"background-color","value":"rgba(0, 0, 0, 0)"},{"name":"background-image","value":"none"},{"name":"background-origin","value":"padding-box"},{"name":"background-position-x","value":"0%"},{"name":"background-position-y","value":"0%"},{"name":"background-repeat","value":"repeat"},{"name":"background-size","value":"auto"},{"name":"baseline-shift","value":"0px"},{"name":"baseline-source","value":"auto"},{"name":"block-size","value":"22px"},{"name":"border-block-end-color","value":"rgb(255, 255, 255)"},{"name":"border-block-end-style","value":"none"},{"name":"border-block-end-width","value":"0px"},{"name":"border-block-start-color","value":"rgb(255, 255, 255)"},{"name":"border-block-start-style","value":"none"},{"name":"border-block-start-width","value":"0px"},{"name":"border-bottom-color","value":"rgb(255, 255, 255)"},{"name":"border-bottom-left-radius","value":"0px"},{"name":"border-bottom-right-radius","value":"0px"},{"name":"border-bottom-style","value":"none"},{"name":"border-bottom-width","value":"0px"},{"name":"border-collapse","value":"separate"},{"name":"border-end-end-radius","value":"0px"},{"name":"border-end-start-radius","value":"0px"},{"name":"border-image-outset","value":"0"},{"name":"border-image-repeat","value":"stretch"},{"name":"border-image-slice","value":"100%"},{"name":"border-image-source","value":"none"},{"name":"border-image-width","value":"1"},{"name":"border-inline-end-color","value":"rgb(255, 255, 255)"},{"name":"border-inline-end-style","value":"none"},{"name":"border-inline-end-width","value":"0px"},{"name":"border-inline-start-color","value":"rgb(255, 255, 255)"},{"name":"border-inline-start-style","value":"none"},{"name":"border-inline-start-width","value":"0px"},{"name":"border-left-color","value":"rgb(255, 255, 255)"},{"name":"border-left-style","value":"none"},{"name":"border-left-width","value":"0px"},{"name":"border-right-color","value":"rgb(255, 255, 255)"},{"name":"border-right-style","value":"none"},{"name":"border-right-width","value":"0px"},{"name":"border-start-end-radius","value":"0px"},{"name":"border-start-start-radius","value":"0px"},{"name":"border-top-color","value":"rgb(255, 255, 255)"},{"name":"border-top-left-radius","value":"0px"},{"name":"border-top-right-radius","value":"0px"},{"name":"border-top-style","value":"none"},{"name":"border-top-width","value":"0px"},{"name":"bottom","value":"auto"},{"name":"box-shadow","value":"none"}]}}`)
	css := gcdapi.NewCSS(NewGCDFakeChromeTargeter(computedStyleJSON))
	ctx := context.Background()
	params := &gcdapi.CSSGetComputedStyleForNodeParams{NodeId: 1}

	results := make([][]*gcdapi.CSSCSSComputedStyleProperty, b.N)
	errors := make([]error, b.N)

	b.ReportAllocs()
	b.ResetTimer()

	for i := 0; i < b.N; i++ {
		results[i], errors[i] = css.GetComputedStyleForNodeWithParams(ctx, params)
	}

	b.StopTimer()

	for i := 0; i < b.N; i++ {
		if errors[i] != nil {
			b.Fatalf("failed to parse message %v", errors[i].Error())
		}

		if len(results[i]) != 106 {
			b.Fatalf("expected 106 results, got %d", len(results[i]))
		}
	}
}

type GCDFakeChromeTargeter struct {
	message *gcdmessage.Message
}

func NewGCDFakeChromeTargeter(responseData []byte) *GCDFakeChromeTargeter {
	return &GCDFakeChromeTargeter{
		message: &gcdmessage.Message{
			ReplyCh: nil,
			Id:      0,
			Data:    responseData,
			Method:  "",
			Target:  nil,
		},
	}
}

func (t *GCDFakeChromeTargeter) GetId() int64 {
	return 0
}

func (t *GCDFakeChromeTargeter) GetApiTimeout() time.Duration {
	return 0
}

func (t *GCDFakeChromeTargeter) GetSendCh() chan *gcdmessage.Message {
	return nil
}

func (t *GCDFakeChromeTargeter) GetDoneCh() chan struct{} {
	return make(chan struct{})
}

func (t *GCDFakeChromeTargeter) SendCustomReturn(_ context.Context, _ *gcdmessage.ParamRequest) (*gcdmessage.Message, error) {
	return t.message, nil
}

func (t *GCDFakeChromeTargeter) SendDefaultRequest(_ context.Context, _ *gcdmessage.ParamRequest) (*gcdmessage.ChromeResponse, error) {
	return nil, nil
}

[wirepair]

should this be "github.com/goccy/go-json" ?

[camswords]

eeep! It should be, cheers. I'll fix it.