fix: [TKC-3038] support brace escaping (#6106)

* fix: support brace escaping Signed-off-by: Vladislav Sukhin <[email protected]> * fixL change escaping Signed-off-by: Vladislav Sukhin <[email protected]> * fix: escape braces and double braces Signed-off-by: Vladislav Sukhin <[email protected]> * fix: add comments Signed-off-by: Vladislav Sukhin <[email protected]> --------- Signed-off-by: Vladislav Sukhin <[email protected]>
kubeshop · Jan 8, 2025 · a5a5555 · a5a5555
1 parent 4e6f2cb
commit a5a5555
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Showing 2 changed files with 42 additions and 1 deletion.
diff --git a/pkg/expressions/parse_test.go b/pkg/expressions/parse_test.go
@@ -210,6 +210,10 @@ func TestCompileEscapeTemplate(t *testing.T) {
 	assert.Equal(t, `foo{{"{{"}}barbaz{{"{{"}}`, MustCompileTemplate(`foo{{"{{bar"}}baz{{"{{"}}`).Template())
 }
 
+func TestCompileEscapeBrace(t *testing.T) {
+	assert.Equal(t, `foo{{"{"}}barbaz{{"{"}}`, MustCompileTemplate(`foo{{"{bar"}}baz{{"{"}}`).Template())
+}
+
 func TestCompileStandardLib(t *testing.T) {
 	assert.Equal(t, `false`, MustCompile(`bool(0)`).String())
 	assert.Equal(t, `true`, MustCompile(`bool(500)`).String())

diff --git a/pkg/expressions/static.go b/pkg/expressions/static.go
@@ -1,6 +1,7 @@
 package expressions
 
 import (
+	"bytes"
 	"encoding/json"
 	"strings"
 )
@@ -69,7 +70,43 @@ func (s *static) Template() string {
 		return ""
 	}
 	v, _ := s.StringValue()
-	return strings.ReplaceAll(v, "{{", "{{\"{{\"}}")
+	// Escape double braces
+	oldValue := strings.ReplaceAll(v, "{{", "{{\"{{\"}}")
+
+	// Escape single brace
+	newValue := oldValue
+	replacement := "{{\"{\"}}"
+	offset := 0
+	extension := 0
+	for index := strings.Index(oldValue[offset:], "{"); index != -1; index = strings.Index(oldValue[offset:], "{") {
+		// make sure no other brace before
+		if offset+index > 0 && string(oldValue[offset+index-1:offset+index]) == "{" {
+			offset += index + 1
+			continue
+		}
+		// make sure no other brace after
+		if offset+index < len(oldValue)-1 && string(oldValue[offset+index+1:offset+index+2]) == "{" {
+			offset += index + 1
+			continue
+		}
+
+		var value bytes.Buffer
+		if index+offset+extension > 0 {
+			value.WriteString(newValue[:index+offset+extension])
+		}
+
+		value.WriteString(replacement)
+
+		if index+offset+extension < len(newValue)-1 {
+			value.WriteString(newValue[index+offset+extension+1:])
+		}
+
+		newValue = value.String()
+		extension += len(replacement) - 1
+		offset += index + 1
+	}
+
+	return newValue
 }
 
 func (s *static) SafeResolve(_ ...Machine) (Expression, bool, error) {