feat(interpolate): add helper (#6266)

sdk/interpolate/interpolate_helper.go

@@ -11,6 +11,7 @@ import (
 	"net/url"
 	"path"
 	"reflect"
+	"strconv"
 	"strings"
 	"text/template"
 
@@ -66,6 +67,7 @@ func init() {
 		"b64enc":       base64encode,
 		"b64dec":       base64decode,
 		"escape":       escape,
+		"stringQuote":  stringQuote,
 		"add": func(i ...interface{}) int64 {
 			var a int64 = 0
 			for _, b := range i {
@@ -375,6 +377,13 @@ func escape(s string) string {
 	return s1
 }
 
+func stringQuote(s string) string {
+	x := strconv.Quote(s)
+	x = strings.TrimPrefix(x, `"`)
+	x = strings.TrimSuffix(x, `"`)
+	return x
+}
+
 func ternary(v, v2, a interface{}) interface{} {
 	if cast.ToBool(a) {
 		return v

sdk/interpolate/interpolate_test.go

@@ -673,3 +673,12 @@ func TestDashReplacementWithµµµ(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, "result.headers.x-cache is a", got)
 }
+
+func TestStringQuote(t *testing.T) {
+	vars := map[string]string{
+		"content": `{"foo": "{\"bar\":\"baz\"}"}`,
+	}
+	got, err := Do("content is {{.content | stringQuote}}", vars)
+	assert.NoError(t, err)
+	assert.Equal(t, `content is {\"foo\": \"{\\\"bar\\\":\\\"baz\\\"}\"}`, got)
+}