validator: escape json-pointer-field when appending

src/json-schema.hpp

@@ -116,6 +116,12 @@ public:
 
 	const std::string url() const;
 
+	// decode and encode strings for ~ and % escape sequences
+	static std::string unescape(const std::string &);
+	static std::string escape(const std::string &);
+
+	// create a new json_uri based in this one and the given uri
+	// resolves relative changes (pathes or pointers) and resets part if proto or hostname changes
 	json_uri derive(const std::string &uri) const
 	{
 		json_uri u = *this;
@@ -123,6 +129,7 @@ public:
 		return u;
 	}
 
+	// append a pointer-field to the pointer-part of this uri
 	json_uri append(const std::string &field) const
 	{
 		json_uri u = *this;
@@ -145,7 +152,6 @@ public:
 	friend std::ostream &operator<<(std::ostream &os, const json_uri &u);
 };
 
-//
 namespace json_schema_draft4
 {
 

src/json-uri.cpp

@@ -25,7 +25,8 @@
  */
 #include "json-schema.hpp"
 
-namespace nlohmann {
+namespace nlohmann
+{
 
 void json_pointer::from_string(const std::string &r)
 {
@@ -124,4 +125,63 @@ std::ostream &operator<<(std::ostream &os, const json_uri &u)
 	return os << u.to_string();
 }
 
+std::string json_uri::unescape(const std::string &src)
+{
+	std::string l = src;
+	std::size_t pos = src.size() - 1;
+
+	do {
+		pos = l.rfind('~', pos);
+
+		if (pos == std::string::npos)
+			break;
+
+		if (pos < l.size() - 1) {
+			switch (l[pos + 1]) {
+			case '0':
+				l.replace(pos, 2, "~");
+				break;
+
+			case '1':
+				l.replace(pos, 2, "/");
+				break;
+
+			default:
+				break;
 			}
+		}
+
+		if (pos == 0)
+			break;
+		pos--;
+	} while (pos != std::string::npos);
+
+	// TODO - percent handling
+
+	return l;
+}
+
+std::string json_uri::escape(const std::string &src)
+{
+	std::vector<std::pair<std::string, std::string>> chars = {
+	    {"~", "~0"},
+	    {"/", "~1"},
+	    {"%", "%25"}};
+
+	std::string l = src;
+
+	for (const auto &c : chars) {
+		std::size_t pos = 0;
+		do {
+			pos = l.find(c.first, pos);
+			if (pos == std::string::npos)
+				break;
+			l.replace(pos, 1, c.second);
+			pos += c.second.size();
+		} while (1);
+	}
+
+	return l;
+}
+
+} // nlohmann

src/json-validator.cpp

@@ -57,12 +57,12 @@ class resolver
 			switch (i.value().type()) {
 
 			case json::value_t::object: // child is object, it is a schema
-				resolve(i.value(), id.append(i.key()));
+				resolve(i.value(), id.append( json_uri::escape(i.key())) );
 				break;
 
 			case json::value_t::array: {
 				std::size_t index = 0;
-				auto child_id = id.append(i.key());
+				auto child_id = id.append(json_uri::escape(i.key()));
 				for (auto &v : i.value()) {
 					if (v.type() == json::value_t::object) // array element is object
 						resolve(v, child_id.append(std::to_string(index)) );