README.md

jsonrpc++

Leightweight C++ JSON-RPC 2.0 library

What it is

jsonrpc++ parses and constructs JSON-RPC 2.0 objects, like

• Request
  • Notification
  • Parameter
• Response
  • Error
• Batch

Example: Parsing a request

jsonrpcpp::entity_ptr entity = jsonrpcpp::Parser::do_parse(R"({"jsonrpc": "2.0", "method": "subtract", "params": {"subtrahend": 23, "minuend": 42}, "id": 3})");
if (entity->is_request())
{
    jsonrpcpp::request_ptr request = dynamic_pointer_cast<jsonrpcpp::Request>(entity);
    if (request->method() == "subtract")
    {
        int result = request->params().get<int>("minuend") - request->params().get<int>("subtrahend");
        jsonrpcpp::Response response(*request, result);
        cout << " Response: " << response.to_json().dump() << "\n";
        //will print: {"jsonrpc": "2.0", "result": 19, "id": 3}
    }
    else
        throw jsonrpcpp::MethodNotFoundException(*request);
}

What it not is

jsonrpc++ is completely transport agnostic, i.e. it doesn't care about transportation of the messages and there is no TCP client or server component shipped with this library.

As JSON backbone JSON for Modern C++ is used.

Some code example

jsonrpcpp::entity_ptr entity =
    jsonrpcpp::Parser::do_parse(R"({"jsonrpc": "2.0", "method": "subtract", "params": {"subtrahend": 23, "minuend": 42}, "id": 3})");
if (entity && entity->is_request())
{
    jsonrpcpp::request_ptr request = dynamic_pointer_cast<jsonrpcpp::Request>(entity);
    cout << " Request: " << request->method() << ", id: " << request->id() << ", has params: " << !request->params().is_null() << "\n";
    if (request->method() == "subtract")
    {
        int result;
        if (request->params().is_array())
            result = request->params().get<int>(0) - request->params().get<int>(1);
        else
            result = request->params().get<int>("minuend") - request->params().get<int>("subtrahend");

        jsonrpcpp::Response response(*request, result);
        cout << " Response: " << response.to_json().dump() << "\n";
    }
    else if (request->method() == "sum")
    {
        int result = 0;
        for (const auto& summand : request->params().param_array)
            result += summand.get<int>();
        jsonrpcpp::Response response(*request, result);
        cout << " Response: " << response.to_json().dump() << "\n";
    }
    else
    {
        throw jsonrpcpp::MethodNotFoundException(*request);
    }
}