feat: reuse compiled expressions (#478)

* feat: reuse compiled expressions

Signed-off-by: Charles-Edouard Brétéché <charles.edouard@nirmata.com>

* todo

Signed-off-by: Charles-Edouard Brétéché <charles.edouard@nirmata.com>

* path

Signed-off-by: Charles-Edouard Brétéché <charles.edouard@nirmata.com>

* ast

Signed-off-by: Charles-Edouard Brétéché <charles.edouard@nirmata.com>

* parsing

Signed-off-by: Charles-Edouard Brétéché <charles.edouard@nirmata.com>

---------

Signed-off-by: Charles-Edouard Brétéché <charles.edouard@nirmata.com>

pkg/engine/assert/assert_test.go

@@ -10,25 +10,20 @@ import (
 )
 
 func TestAssert(t *testing.T) {
-	type args struct {
-		assertion Assertion
+	tests := []struct {
+		name      string
+		assertion any
 		value     any
 		bindings  binding.Bindings
-	}
-	tests := []struct {
-		name    string
-		args    args
-		want    field.ErrorList
-		wantErr bool
+		want      field.ErrorList
+		wantErr   bool
 	}{{
 		name: "nil vs empty object",
-		args: args{
-			assertion: Parse(context.TODO(), map[string]any{
-				"foo": map[string]any{},
-			}),
-			value: map[string]any{
-				"foo": nil,
-			},
+		assertion: map[string]any{
+			"foo": map[string]any{},
+		},
+		value: map[string]any{
+			"foo": nil,
 		},
 		want: field.ErrorList{
 			&field.Error{
@@ -40,22 +35,22 @@ func TestAssert(t *testing.T) {
 		wantErr: false,
 	}, {
 		name: "not nil vs empty object",
-		args: args{
-			assertion: Parse(context.TODO(), map[string]any{
-				"foo": map[string]any{},
-			}),
-			value: map[string]any{
-				"foo": map[string]any{
-					"bar": 42,
-				},
+		assertion: map[string]any{
+			"foo": map[string]any{},
+		},
+		value: map[string]any{
+			"foo": map[string]any{
+				"bar": 42,
 			},
 		},
 		want:    nil,
 		wantErr: false,
 	}}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, err := Assert(context.TODO(), nil, tt.args.assertion, tt.args.value, tt.args.bindings)
+			parsed, err := Parse(context.TODO(), nil, tt.assertion)
+			tassert.NoError(t, err)
+			got, err := Assert(context.TODO(), nil, parsed, tt.value, tt.bindings)
 			if tt.wantErr {
 				tassert.Error(t, err)
 			} else {

pkg/engine/assert/expression.go

@@ -4,7 +4,9 @@ import (
 	"context"
 	"reflect"
 	"regexp"
+	"sync"
 
+	"github.com/jmespath-community/go-jmespath/pkg/parsing"
 	reflectutils "github.com/kyverno/kyverno-json/pkg/utils/reflect"
 )
 
@@ -21,6 +23,7 @@ type expression struct {
 	statement   string
 	binding     string
 	engine      string
+	ast         func() (parsing.ASTNode, error)
 }
 
 func parseExpressionRegex(_ context.Context, in string) *expression {
@@ -61,5 +64,12 @@ func parseExpression(ctx context.Context, value any) *expression {
 	if reflectutils.GetKind(value) != reflect.String {
 		return nil
 	}
-	return parseExpressionRegex(ctx, reflect.ValueOf(value).String())
+	exp := parseExpressionRegex(ctx, reflect.ValueOf(value).String())
+	if exp != nil && exp.engine == "jp" {
+		exp.ast = sync.OnceValues(func() (parsing.ASTNode, error) {
+			parser := parsing.NewParser()
+			return parser.Parse(exp.statement)
+		})
+	}
+	return exp
 }