support non-local remote transports (#57)

* support non-local remote transports

* fix LogosResult

* allow getting client over specific transport

* fix ssl

* investiage ssl error

* pr comments

* allow transport set configuration on any module

* pr comments

* add docs

* pr comments

* propagate only non-qt dependencies

* restore ABI compatibility

cpp/implementations/plain/json_codec.cpp

@@ -0,0 +1,28 @@
+#include "json_codec.h"
+#include "json_mapping.h"
+
+#include <nlohmann/json.hpp>
+
+namespace logos::plain {
+
+using json = nlohmann::json;
+
+std::vector<uint8_t> JsonCodec::encode(const AnyMessage& msg)
+{
+    const json j = messageToJson(msg);
+    const std::string s = j.dump();
+    return std::vector<uint8_t>(s.begin(), s.end());
+}
+
+AnyMessage JsonCodec::decode(MessageType tag, const uint8_t* data, std::size_t len)
+{
+    json j;
+    try {
+        j = json::parse(data, data + len);
+    } catch (const std::exception& e) {
+        throw CodecError(std::string("json parse failed: ") + e.what());
+    }
+    return jsonToMessage(tag, j);
+}
+
+} // namespace logos::plain