Read Handler
Setup the onReadRequest handler of the CommonBackend class to handle read events. Processing a read request for a non-remote system in direct read mode is the same as non-direct read mode.
This handler takes a protobuf message of type FrontendRequest. You can
process multiple read requests in parallel threads where each read request has its own
ID.
Example
commonBackend.onReadRequest([&](const FrontendRequest& request)
{
logDebug("Backend processes onReadRequest request: \n" + request.DebugString());
if (doExit || !request.has_query())
{
return;
}
// function to send a response to WinCC OA
const auto sendReadResponseFunc = [&](const ReadResponse& response)
{
commonBackend.makeReadResponseSender().sendReadResponse(request, response);
};
ReadHandler::processReadRequest(sendReadResponseFunc, request);
});
All active backends accept read requests (even if they do not contain the requested DPEs).
