http/request: add constructor

include/opendht/http.h

@@ -212,6 +212,7 @@ public:
     using OnDataCb = std::function<void(const char* at, size_t length)>;
     using OnStateChangeCb = std::function<void(State state, const Response& response)>;
     using OnJsonCb = std::function<void(Json::Value value, unsigned int status_code)>;
+    using OnDoneCb = std::function<void(const Response& response)>;
 
     // resolves implicitly
     Request(asio::io_context& ctx, const std::string& url, const Json::Value& json, OnJsonCb jsoncb,
@@ -219,6 +220,7 @@ public:
     Request(asio::io_context& ctx, const std::string& url, std::shared_ptr<dht::Logger> logger = {});
     Request(asio::io_context& ctx, const std::string& host, const std::string& service,
             const bool ssl = false, std::shared_ptr<dht::Logger> logger = {});
+    Request(asio::io_context& ctx, const std::string& url, OnDoneCb onDone, std::shared_ptr<dht::Logger> logger = {});
 
     // user defined resolver
     Request(asio::io_context& ctx, std::shared_ptr<Resolver> resolver, sa_family_t family = AF_UNSPEC);

src/http.cpp

@@ -443,11 +443,13 @@ Request::Request(asio::io_context& ctx, const std::string& url, const Json::Valu
         if (state != Request::State::DONE)
             return;
         Json::Value json;
+        if (response.status_code != 0) {
             std::string err;
             Json::CharReaderBuilder rbuilder;
             auto reader = std::unique_ptr<Json::CharReader>(rbuilder.newCharReader());
             if (!reader->parse(response.body.data(), response.body.data() + response.body.size(), &json, &err) and logger_)
                 logger_->e("[http:request:%i] can't parse response to json", id_, err.c_str());
+        }
         if (jsoncb)
             jsoncb(json, response.status_code);
     });
@@ -460,6 +462,15 @@ Request::Request(asio::io_context& ctx, const std::string& url, std::shared_ptr<
     init_default_headers();
 }
 
+Request::Request(asio::io_context& ctx, const std::string& url, OnDoneCb onDone, std::shared_ptr<dht::Logger> logger)
+    : logger_(logger), id_(Request::ids_++), ctx_(ctx), resolver_(std::make_shared<Resolver>(ctx, url, logger))
+{
+    add_on_state_change_callback([this, onDone](State state, const Response& response){
+        if (state == Request::State::DONE)
+            onDone(response);
+    });
+}
+
 Request::Request(asio::io_context& ctx, const std::string& host, const std::string& service,
                  const bool ssl, std::shared_ptr<dht::Logger> logger)
     : logger_(logger), id_(Request::ids_++), ctx_(ctx),