Merge branch 'allow-escaped-json' into envoy-gloo

Author: jbohanon

include/inja/config.hpp

@@ -80,6 +80,7 @@ struct ParserConfig {
  */
 struct RenderConfig {
   bool throw_at_missing_includes {true};
+  bool escape_strings {};
 };
 
 } // namespace inja

include/inja/environment.hpp

@@ -88,6 +88,11 @@ class Environment {
     lexer_config.notation = notation;
   }
 
+  /// Sets the config for rendering strings raw or escaped
+  void set_escape_strings(bool escape_strings) {
+      render_config.escape_strings = escape_strings;
+  }
+
   /// Sets the element notation syntax
   void set_search_included_templates_in_files(bool search_in_files) {
     parser_config.search_included_templates_in_files = search_in_files;

include/inja/renderer.hpp

@@ -55,7 +55,20 @@ class Renderer : public NodeVisitor {
 
   void print_data(const std::shared_ptr<json> value) {
     if (value->is_string()) {
-      *output_stream << value->get_ref<const json::string_t&>();
+      std::string val;
+      if (config.escape_strings) {
+        // get the value as a dump() to properly escape values
+        val = value->dump();
+
+        // strip the leading and trailing " characters that are added by dump()
+        // if C++20 is adopted, val.starts_with and val.ends_with would clean this up a bit
+        val = val.substr(0,1) == "\"" && val.substr(val.length()-1,1) == "\""
+            ? val.substr(1, val.length()-2)
+            : val;
+      } else {
+        val = value->get_ref<const json::string_t&>();
+      }
+      *output_stream << val;
     } else if (value->is_number_integer()) {
       *output_stream << value->get<const json::number_integer_t>();
     } else if (value->is_null()) {

single_include/inja/inja.hpp

@@ -906,6 +906,7 @@ struct ParserConfig {
  */
 struct RenderConfig {
   bool throw_at_missing_includes {true};
+  bool escape_strings {};
 };
 
 } // namespace inja
@@ -2150,7 +2151,16 @@ class Renderer : public NodeVisitor {
 
   void print_data(const std::shared_ptr<json> value) {
     if (value->is_string()) {
-      *output_stream << value->get_ref<const json::string_t&>();
+      std::string val;
+      if (config.escape_strings) {
+        val = value->dump();
+        val = val.substr(0,1) == "\"" && val.substr(val.length()-1,1) == "\""
+            ? val.substr(1, val.length()-2)
+            : val;
+      } else {
+        val = value->get_ref<const json::string_t&>();
+      }
+      *output_stream << val;
     } else if (value->is_number_integer()) {
       *output_stream << value->get<const json::number_integer_t>();
     } else if (value->is_null()) {
@@ -2803,6 +2813,11 @@ class Environment {
     lexer_config.notation = notation;
   }
 
+  /// Sets the config for rendering strings raw or escaped
+  void set_escape_strings(bool escape_strings) {
+      render_config.escape_strings = escape_strings;
+  }
+
   /// Sets the element notation syntax
   void set_search_included_templates_in_files(bool search_in_files) {
     parser_config.search_included_templates_in_files = search_in_files;

test/test-renderer.cpp

@@ -21,6 +21,7 @@ TEST_CASE("types") {
   data["json_pointers"]["example.com"] = "online";
   data["json_pointers"]["and/or"] = "slash";
   data["json_pointers"]["and~or"] = "tilde";
+  data["quoted"] = "\"quoted value\"";
 
   SUBCASE("basic") {
     CHECK(env.render("", data) == "");
@@ -48,6 +49,11 @@ TEST_CASE("types") {
     CHECK(env.render("{{ json_pointers/and~0or }}", data) == "tilde");
     env.set_element_notation(inja::ElementNotation::Dot);
 
+    CHECK(env.render(R"EOF({"Value":"{{ quoted }}"})EOF", data) == R"EOF({"Value":""quoted value""})EOF");
+    env.set_escape_strings(true);
+    CHECK(env.render(R"EOF({"Value":"{{ quoted }}"})EOF", data) == R"EOF({"Value":"\"quoted value\""})EOF");
+    env.set_escape_strings(false);
+
     CHECK_THROWS_WITH(env.render("{{unknown}}", data), "[inja.exception.render_error] (at 1:3) variable 'unknown' not found");
   }