Function json_query_examples

examples/src/jsonpath_examples.cpp:24–95

namespace jsonpointer = jsoncons::jsonpointer;

void json_query_examples() 
{
    std::ifstream is("./input/store.json");
    auto booklist = jsoncons::json::parse(is);

    // The authors of books that are cheaper than $10
    jsoncons::json result1 = jsonpath::json_query(booklist, "$.store.book[?(@.price < 10)].author");
    std::cout << "(1) " << result1 << "\n";

    // The number of books
    jsoncons::json result2 = jsonpath::json_query(booklist, "length($..book)");
    std::cout << "(2) " << result2 << "\n";

    // The third book
    jsoncons::json result3 = jsonpath::json_query(booklist, "$..book[2]");
    std::cout << "(3)\n" << pretty_print(result3) << "\n";

    // All books whose author's name starts with Evelyn
    jsoncons::json result4 = jsonpath::json_query(booklist, "$.store.book[?(@.author =~ /Evelyn.*?/)]");
    std::cout << "(4)\n" << pretty_print(result4) << "\n";

    // The titles of all books that have isbn number
    jsoncons::json result5 = jsonpath::json_query(booklist, "$..book[?(@.isbn)].title");
    std::cout << "(5) " << result5 << "\n";

    // All authors and titles of books
    jsoncons::json result6 = jsonpath::json_query(booklist, "$['store']['book']..['author','title']");
    std::cout << "(6)\n" << pretty_print(result6) << "\n";

    // Union of two ranges of book titles
    jsoncons::json result7 = jsonpath::json_query(booklist, "$..book[1:2,2:4].title");
    std::cout << "(7) " << result7 << "\n";

    // Union of a subset of book titles identified by index
    jsoncons::json result8 = jsonpath::json_query(booklist, "$.store[@.book[0].title,@.book[1].title,@.book[3].title]");
    std::cout << "(8) " << result8 << "\n";

    // Union of third book title and all book titles with price > 10
    jsoncons::json result9 = jsonpath::json_query(booklist, "$.store[@.book[3].title,@.book[?(@.price > 10)].title]");
    std::cout << "(9) " << result9 << "\n";

    // Intersection of book titles with category fiction and price < 15
    jsoncons::json result10 = jsonpath::json_query(booklist, "$.store.book[?(@.category == 'fiction' && @.price < 15)].title");
    std::cout << "(10) " << result10 << "\n";

    // Normalized path expressions
    jsoncons::json result11 = jsonpath::json_query(booklist, "$.store.book[?(@.author =~ /Evelyn.*?/)]", jsonpath::result_options::path);
    std::cout << "(11) " << result11 << "\n";

    // All titles whose author's second name is 'Waugh'
    jsoncons::json result12 = jsonpath::json_query(booklist,"$.store.book[?(tokenize(@.author,'\\\\s+')[1] == 'Waugh')].title");
    std::cout << "(12) " << result12 << "\n";

    // All keys in the second book
    jsoncons::json result13 = jsonpath::json_query(booklist,"keys($.store.book[1])");
    std::cout << "(13) " << result13 << "\n";

    jsoncons::json result14 = jsonpath::json_query(booklist,"$.store.book[?(ceil(@.price) == 9)]");