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/**
* @file
*
* @brief Demonstrates how to resolve JSON pointers against the current document
*
*/
#include <iostream>
#include <valijson/adapters/rapidjson_adapter.hpp>
#include <valijson/internal/json_pointer.hpp>
#include <valijson/internal/json_reference.hpp>
#include <valijson/utils/rapidjson_utils.hpp>
using std::cerr;
using std::cout;
using std::endl;
template<typename AdapterType>
std::string maybeResolveRef(const AdapterType &value, const AdapterType &root)
{
if (!value.isObject()) {
// Not an object, therefore not a JSON reference
return "";
}
const auto &object = value.getObject();
const auto itr = object.find("$ref");
if (itr == object.end()) {
// Object does not contain $ref property
return "";
}
const AdapterType maybeRef = itr->second;
if (!maybeRef.isString()) {
return "[$ref did not contain a string value]";
}
// Attempt to extract a JSON pointer
const std::string ref = maybeRef.getString();
const auto maybePointer = valijson::internal::json_reference::getJsonReferencePointer(ref);
if (!maybePointer) {
return "[$ref did not contain valid JSON pointer]";
}
const auto refAdapter = valijson::internal::json_pointer::resolveJsonPointer(root, *maybePointer);
if (!refAdapter.maybeString()) {
return "[$ref did not point to a string value]";
}
return refAdapter.asString();
}
template<typename AdapterType>
void iterateJsonObject(const AdapterType &adapter)
{
if (!adapter.maybeObject()) {
cout << "Not an object." << endl;
return;
}
cout << "Object members:" << endl;
// JSON objects are an unordered collection of key-value pairs,
// so the members of the object may be printed in an order that is
// different to that in the source JSON document.
for (auto member : adapter.asObject()) {
// The key is a std::string that can be accessed using 'first'
cout << " " << member.first << ": ";
// The value is just another Adapter, and can be accessed using 'second'
const AdapterType &value = member.second;
if (value.maybeString()) {
cout << value.asString();
} else {
cout << maybeResolveRef(value, adapter);
}
cout << endl;
}
}
void usingJsonCppWithTemplateFn(const char *filename)
{
rapidjson::Document document;
if (!valijson::utils::loadDocument(filename, document)) {
return;
}
valijson::adapters::RapidJsonAdapter adapter(document);
iterateJsonObject(adapter);
}
int main(int argc, char **argv)
{
if (argc != 2) {
cerr << "Usage: " << endl;
cerr << " " << argv[0] << " <filename>" << endl;
return 1;
}
// Load the document using jsoncpp and iterate over array using function template
cout << "-- Resolving JSON pointers using RapidJSON --" << endl;
usingJsonCppWithTemplateFn(argv[1]);
cout << endl;
return 0;
}
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