Futher optimize json parsing and editing performance

ajson/filter.go

@@ -1,21 +1,18 @@
-package json
+package ajson
 
 import (
 	"bytes"
-	"crypto/sha1"
+
+	"github.com/cespare/xxhash/v2"
 )
 
 func Filter(w *bytes.Buffer, b []byte, keys []string) error {
-	state := expectKey
 	var err error
 
-	kmap := make(map[[20]byte]struct{}, len(keys))
+	kmap := make(map[uint64]struct{}, len(keys))
 
-	for _, k := range keys {
+	for i := range keys {
-		h := sha1.Sum([]byte(k))
+		kmap[xxhash.Sum64String(keys[i])] = struct{}{}
-		if _, ok := kmap[h]; !ok {
-			kmap[h] = struct{}{}
-		}
 	}
 
 	// is an list
@@ -29,7 +26,8 @@ func Filter(w *bytes.Buffer, b []byte, keys []string) error {
 
 	s, e, d := 0, 0, 0
 
-	kf := false
+	var k []byte
+	state := expectKey
 
 	for i := 0; i < len(b); i++ {
 		if state == expectObjClose || state == expectListClose {
@@ -67,8 +65,7 @@ func Filter(w *bytes.Buffer, b []byte, keys []string) error {
 			}
 		case state == expectKeyClose && b[i] == '"':
 			state = expectColon
-			k := b[(s + 1):i]
+			k = b[(s + 1):i]
-			_, kf = kmap[sha1.Sum(k)]
 
 		case state == expectColon && b[i] == ':':
 			state = expectValue
@@ -115,7 +112,7 @@ func Filter(w *bytes.Buffer, b []byte, keys []string) error {
 			cb := b[s:(e + 1)]
 			e = 0
 
-			if !kf {
+			if _, ok := kmap[xxhash.Sum64(k)]; !ok {
 				continue
 			}
 

ajson/get.go

@@ -1,7 +1,7 @@
-package json
+package ajson
 
 import (
-	"crypto/sha1"
+	"github.com/cespare/xxhash/v2"
 )
 
 const (
@@ -21,27 +21,35 @@ type Field struct {
 	Value []byte
 }
 
+func Value(b []byte) []byte {
+	e := (len(b) - 1)
+	switch {
+	case b[0] == '"' && b[e] == '"':
+		return b[1:(len(b) - 1)]
+	case b[0] == '[' && b[e] == ']':
+		return nil
+	case b[0] == '{' && b[e] == '}':
+		return nil
+	default:
+		return b
+	}
+}
+
 func Get(b []byte, keys [][]byte) []Field {
-	s := 0
+	kmap := make(map[uint64]struct{}, len(keys))
-	state := expectKey
 
-	kmap := make(map[[20]byte]struct{}, len(keys))
+	for i := range keys {
-
+		kmap[xxhash.Sum64(keys[i])] = struct{}{}
-	for _, k := range keys {
-		h := sha1.Sum(k)
-		if _, ok := kmap[h]; !ok {
-			kmap[h] = struct{}{}
-		}
 	}
 
-	prealloc := 20
+	res := make([]Field, 20)
-	res := make([]Field, prealloc)
 
 	s, e, d := 0, 0, 0
 
-	var kf bool
 	var k []byte
+	state := expectKey
 
+	n := 0
 	for i := 0; i < len(b); i++ {
 		if state == expectObjClose || state == expectListClose {
 			switch b[i] {
@@ -60,7 +68,6 @@ func Get(b []byte, keys [][]byte) []Field {
 		case state == expectKeyClose && b[i] == '"':
 			state = expectColon
 			k = b[(s + 1):i]
-			_, kf = kmap[sha1.Sum(k)]
 
 		case state == expectColon && b[i] == ':':
 			state = expectValue
@@ -110,13 +117,11 @@ func Get(b []byte, keys [][]byte) []Field {
 		}
 
 		if e != 0 {
-			if kf {
+			_, ok := kmap[xxhash.Sum64(k)]
-				if len(res) == cap(res) {
+
-					r := make([]Field, 0, (len(res) * 2))
+			if ok {
-					copy(r, res)
+				res[n] = Field{k, b[s:(e + 1)]}
-					res = r
+				n++
-				}
-				res = append(res, Field{k, b[s:(e + 1)]})
 			}
 
 			state = expectKey
@@ -124,5 +129,5 @@ func Get(b []byte, keys [][]byte) []Field {
 		}
 	}
 
-	return res
+	return res[:n]
 }

ajson/json_test.go

@@ -1,4 +1,4 @@
-package json
+package ajson
 
 import (
 	"bytes"
@@ -130,7 +130,7 @@ var (
 	}`
 
 	input4 = `
-	[{
+	{ "users" : [{
 		"id": 1,
 		"full_name": "Sidney Stroman",
 		"email": "user0@demo.com",
@@ -148,7 +148,7 @@ var (
 		"full_name": "Jerry Dickinson",
 		"email": "user1@demo.com",
 		"__twitter_id": [{ "name": "hello" }, { "name": "world"}]
-	}]`
+	}] }`
 )
 
 func TestGet(t *testing.T) {
@@ -194,6 +194,28 @@ func TestGet(t *testing.T) {
 	}
 }
 
+func TestValue(t *testing.T) {
+	v1 := []byte("12345")
+	if !bytes.Equal(Value(v1), v1) {
+		t.Fatal("Number value invalid")
+	}
+
+	v2 := []byte(`"12345"`)
+	if !bytes.Equal(Value(v2), []byte(`12345`)) {
+		t.Fatal("String value invalid")
+	}
+
+	v3 := []byte(`{ "hello": "world" }`)
+	if Value(v3) != nil {
+		t.Fatal("Object value is not nil", Value(v3))
+	}
+
+	v4 := []byte(`[ "hello", "world" ]`)
+	if Value(v4) != nil {
+		t.Fatal("List value is not nil")
+	}
+}
+
 func TestFilter(t *testing.T) {
 	var b bytes.Buffer
 	Filter(&b, []byte(input2), []string{"id", "full_name", "embed"})
@@ -206,13 +228,22 @@ func TestFilter(t *testing.T) {
 }
 
 func TestStrip(t *testing.T) {
-	value := Strip([]byte(input3), []string{"data", "users"})
+	path1 := [][]byte{[]byte("data"), []byte("users")}
+	value1 := Strip([]byte(input3), path1)
 
 	expected := []byte(`[{"id":1,"embed":{"id":8}},{"id":2},{"id":3},{"id":4},{"id":5},{"id":6},{"id":7},{"id":8},{"id":9},{"id":10},{"id":11},{"id":12},{"id":13}]`)
 
-	if bytes.Equal(value, expected) == false {
+	if bytes.Equal(value1, expected) == false {
-		t.Log(value)
+		t.Log(value1)
-		t.Error("Does not match expected json")
+		t.Error("[Valid path] Does not match expected json")
+	}
+
+	path2 := [][]byte{[]byte("boo"), []byte("hoo")}
+	value2 := Strip([]byte(input3), path2)
+
+	if bytes.Equal(value2, []byte(input3)) == false {
+		t.Log(value2)
+		t.Error("[Invalid path] Does not match expected json")
 	}
 }
 
@@ -229,7 +260,7 @@ func TestReplace(t *testing.T) {
 		{[]byte("some_list"), []byte(`[{"id":1,"embed":{"id":8}},{"id":2},{"id":3},{"id":4},{"id":5},{"id":6},{"id":7},{"id":8},{"id":9},{"id":10},{"id":11},{"id":12},{"id":13}]`)},
 	}
 
-	expected := `[{
+	expected := `{ "users" : [{
 		"id": 1,
 		"full_name": "Sidney Stroman",
 		"email": "user0@demo.com",
@@ -247,7 +278,7 @@ func TestReplace(t *testing.T) {
 		"full_name": "Jerry Dickinson",
 		"email": "user1@demo.com",
 		"__twitter_id":"1234567890"
-	}]`
+	}] }`
 
 	err := Replace(&buf, []byte(input4), from, to)
 	if err != nil {
@@ -255,6 +286,23 @@ func TestReplace(t *testing.T) {
 	}
 
 	if buf.String() != expected {
+		t.Log(buf.String())
+		t.Error("Does not match expected json")
+	}
+}
+
+func TestReplaceEmpty(t *testing.T) {
+	var buf bytes.Buffer
+
+	json := `{ "users" : [{"id":1,"full_name":"Sidney Stroman","email":"user0@demo.com","__users_twitter_id":"2048666903444506956"}, {"id":2,"full_name":"Jerry Dickinson","email":"user1@demo.com","__users_twitter_id":"2048666903444506956"}, {"id":3,"full_name":"Kenna Cassin","email":"user2@demo.com","__users_twitter_id":"2048666903444506956"}, {"id":4,"full_name":"Mr. Pat Parisian","email":"rodney@kautzer.biz","__users_twitter_id":"2048666903444506956"}, {"id":5,"full_name":"Bette Ebert","email":"janeenrath@goyette.com","__users_twitter_id":"2048666903444506956"}, {"id":6,"full_name":"Everett Kiehn","email":"michael@bartoletti.com","__users_twitter_id":"2048666903444506956"}, {"id":7,"full_name":"Katrina Cronin","email":"loretaklocko@framivolkman.org","__users_twitter_id":"2048666903444506956"}, {"id":8,"full_name":"Caroll Orn Sr.","email":"joannarau@hegmann.io","__users_twitter_id":"2048666903444506956"}, {"id":9,"full_name":"Gwendolyn Ziemann","email":"renaytoy@rutherford.co","__users_twitter_id":"2048666903444506956"}, {"id":10,"full_name":"Mrs. Rosann Fritsch","email":"holliemosciski@thiel.org","__users_twitter_id":"2048666903444506956"}, {"id":11,"full_name":"Arden Koss","email":"cristobalankunding@howewelch.org","__users_twitter_id":"2048666903444506956"}, {"id":12,"full_name":"Brenton Bauch PhD","email":"renee@miller.co","__users_twitter_id":"2048666903444506956"}, {"id":13,"full_name":"Daine Gleichner","email":"andrea@nienow.co","__users_twitter_id":"2048666903444506956"}] }`
+
+	err := Replace(&buf, []byte(json), []Field{}, []Field{})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if buf.String() != json {
+		t.Log(buf.String())
 		t.Error("Does not match expected json")
 	}
 }
@@ -284,10 +332,11 @@ func BenchmarkFilter(b *testing.B) {
 }
 
 func BenchmarkStrip(b *testing.B) {
+	path := [][]byte{[]byte("data"), []byte("users")}
 	b.ReportAllocs()
 
 	for n := 0; n < b.N; n++ {
-		Strip([]byte(input3), []string{"data", "users"})
+		Strip([]byte(input3), path)
 	}
 }
 

ajson/replace.go

@@ -1,9 +1,10 @@
-package json
+package ajson
 
 import (
 	"bytes"
-	"crypto/sha1"
 	"errors"
+
+	"github.com/cespare/xxhash/v2"
 )
 
 func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
@@ -11,31 +12,25 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 		return errors.New("'from' and 'to' must be of the same length")
 	}
 
-	fmap := make(map[[20]byte]int, (len(from) * 2))
+	h := xxhash.New()
-	tmap := make(map[[20]byte]int, (len(from)))
+	tmap := make(map[uint64]int, len(from))
 
 	for i, f := range from {
-		h1 := sha1.Sum(f.Key)
+		h.Write(f.Key)
-		n, ok := fmap[h1]
+		h.Write(f.Value)
-		if !ok {
-			fmap[h1] = i
-			n = i
-		}
 
-		h2 := sha1.Sum(f.Value)
+		tmap[h.Sum64()] = i
-		fmap[h2] = n
+		h.Reset()
-		tmap[h2] = i
 	}
 
-	state := expectKey
-	ws, we := 0, len(b)
-
 	s, e, d := 0, 0, 0
-	fi := -1
+
+	state := expectKey
+	ws, we := -1, len(b)
 
 	for i := 0; i < len(b); i++ {
 		// skip any left padding whitespace
-		if ws == 0 && (b[i] == '{' || b[i] == '[') {
+		if ws == -1 && (b[i] == '{' || b[i] == '[') {
 			ws = i
 		}
 
@@ -55,11 +50,8 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 
 		case state == expectKeyClose && b[i] == '"':
 			state = expectColon
-			h1 := sha1.Sum(b[(s + 1):i])
+			h.Write(b[(s + 1):i])
-			if n, ok := fmap[h1]; ok {
 			we = s
-				fi = n
-			}
 
 		case state == expectColon && b[i] == ':':
 			state = expectValue
@@ -109,43 +101,58 @@ func Replace(w *bytes.Buffer, b []byte, from, to []Field) error {
 		if e != 0 {
 			e++
 
-			h2 := sha1.Sum(b[s:e])
+			h.Write(b[s:e])
-			replace := false
+			n, ok := tmap[h.Sum64()]
+			h.Reset()
 
-			if n, ok1 := fmap[h2]; ok1 && n == fi {
+			if ok {
-				ti, ok2 := tmap[h2]
-
-				if ok2 {
 				if _, err := w.Write(b[ws:(we + 1)]); err != nil {
 					return err
 				}
-					if _, err := w.Write(to[ti].Key); err != nil {
+
+				if len(to[n].Key) != 0 {
+					var err error
+
+					if _, err := w.Write(to[n].Key); err != nil {
 						return err
 					}
 					if _, err := w.WriteString(`":`); err != nil {
 						return err
 					}
-					if _, err := w.Write(to[ti].Value); err != nil {
+					if len(to[n].Value) != 0 {
+						_, err = w.Write(to[n].Value)
+					} else {
+						_, err = w.WriteString("null")
+					}
+					if err != nil {
 						return err
 					}
-					replace = true
+
+					ws = e
+				} else if b[e] == ',' {
+					ws = e + 1
+				} else {
 					ws = e
 				}
 			}
 
-			if !replace && (b[s] == '[' || b[s] == '{') {
+			if !ok && (b[s] == '[' || b[s] == '{') {
 				// the i++ in the for loop will add 1 so we account for that (s - 1)
 				i = s - 1
 			}
 
 			state = expectKey
 			we = len(b)
-			fi = -1
 			e = 0
 			d = 0
 		}
 	}
 
+	if ws == -1 || (ws == 0 && we == len(b)) {
+		w.Write(b)
+	} else {
 		w.Write(b[ws:we])
+	}
+
 	return nil
 }

ajson/strip.go

@@ -1,21 +1,16 @@
-package json
+package ajson
 
 import (
 	"bytes"
 )
 
-func Strip(b []byte, path []string) []byte {
+func Strip(b []byte, path [][]byte) []byte {
-	s := 0
-	state := expectKey
-
-	kb := make([][]byte, 0, len(path))
-	for _, k := range path {
-		kb = append(kb, []byte(k))
-	}
-
 	s, e, d := 0, 0, 0
-	ki := 0
+
+	ob := b
+	pi := 0
 	pm := false
+	state := expectKey
 
 	for i := 0; i < len(b); i++ {
 		if state == expectObjClose || state == expectListClose {
@@ -34,12 +29,12 @@ func Strip(b []byte, path []string) []byte {
 
 		case state == expectKeyClose && b[i] == '"':
 			state = expectColon
-			if ki == len(kb) {
+			if pi == len(path) {
-				ki = 0
+				pi = 0
 			}
-			pm = bytes.Equal(b[(s+1):i], kb[ki])
+			pm = bytes.Equal(b[(s+1):i], path[pi])
 			if pm {
-				ki++
+				pi++
 			}
 
 		case state == expectColon && b[i] == ':':
@@ -92,7 +87,7 @@ func Strip(b []byte, path []string) []byte {
 				b = b[s:(e + 1)]
 				i = 0
 
-				if ki == len(kb) {
+				if pi == len(path) {
 					return b
 				}
 			}
@@ -102,5 +97,5 @@ func Strip(b []byte, path []string) []byte {
 		}
 	}
 
-	return nil
+	return ob
 }