Use libvariant to validate JSON schema against JSON data

schema_validate.cpp

// c++ -I/usr/local/include -L/usr/local/lib -lVariant schema_validate.cpp

#include <cstdio>
#include <iostream>
#include <iomanip>
#include <algorithm>
#include <fstream>
#include <sstream>
#include <iterator>
#include <memory>

#include <libgen.h>

#include <Variant/Schema.h>
#include <Variant/Variant.h>
#include <Variant/Parser.h>
#include <Variant/ParserInput.h>

using namespace libvariant;
using namespace std;

void dump(const string& filename, ostream& out) {
    ifstream in(filename.c_str());
    in.unsetf(ios::skipws);
    copy(istream_iterator<char>(in)
         , istream_iterator<char>()
         , ostream_iterator<char>(out));
    out << endl;
}

int main(int argc, const char * argv[]) {
    if(argc < 3) {
        cerr << "usage: " << basename((char*)argv[0]) << " <schema-file> <test-file>" << endl;
        exit(EXIT_FAILURE);
    }

    const std::string schema_file = argv[1];
    const std::string test_file = argv[2];

    clog << "Schema:" << endl;
    dump(schema_file, cout);

    Variant schema;
    try {
        schema = DeserializeJSONFile(schema_file.c_str());
    } catch(const exception& e) {
        cerr << e.what() << endl;
        exit(EXIT_FAILURE);
    }

    clog << "Test:" << endl;
    dump(test_file, cout);

    Variant test;
    try {
        test = DeserializeJSONFile(test_file.c_str());
    } catch(const exception& e) {
        cerr << e.what() << endl;
        exit(EXIT_FAILURE);
    }


    SchemaResult r = SchemaValidate(schema, test);
    if(r.Error()) {
        cerr << r.PrettyPrintMessage() << endl;
    } else {
        cout << "validation success!" << endl;
    }

    return EXIT_SUCCESS;
}