[util] Add method http_get

src/.formatted-files

@@ -154,6 +154,8 @@ unlimited.cpp
 unlimited.h
 util.cpp
 util.h
+utilhttp.cpp
+utilhttp.h
 utilmoneystr.cpp
 utilmoneystr.h
 utilstrencodings.cpp

src/Makefile.am

@@ -195,6 +195,7 @@ BITCOIN_CORE_H = \
   ui_interface.h \
   undo.h \
   unlimited.h \
+  utilhttp.h \
   stat.h \
   tweak.h \
   requestManager.h \
@@ -291,6 +292,7 @@ libbitcoin_server_a_SOURCES = \
   txorphanpool.cpp \
   tweak.cpp \
   unlimited.cpp \
+  utilhttp.cpp \
   requestManager.cpp \
   validation/forks.cpp \
   validation/validation.cpp \

src/utilhttp.cpp

@@ -0,0 +1,52 @@
+#include "utilhttp.h"
+#include "util.h"
+
+#include <boost/asio/connect.hpp>
+#include <boost/asio/ip/tcp.hpp>
+#include <boost/beast/core.hpp>
+#include <boost/beast/http.hpp>
+#include <boost/beast/version.hpp>
+#include <cstdlib>
+#include <iostream>
+#include <sstream>
+#include <stdexcept>
+
+using tcp = boost::asio::ip::tcp;
+namespace http = boost::beast::http;
+
+std::stringstream http_get(const std::string &host,
+    const std::string &service, /* aka port number */
+    const std::string &target)
+{
+    boost::asio::io_context ioc;
+    tcp::resolver resolver{ioc};
+    tcp::socket socket{ioc};
+
+    // resolve host
+    auto const results = resolver.resolve(host, service);
+
+    // send request
+    boost::asio::connect(socket, results.begin(), results.end());
+    int version = 11; // HTTP 1.1
+    http::request<http::string_body> req{http::verb::get, target, version};
+    req.set(http::field::host, host);
+    req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
+    http::write(socket, req);
+
+    // read response
+    boost::beast::flat_buffer buffer;
+    http::response<http::dynamic_body> res;
+    http::read(socket, buffer, res);
+    std::stringstream ss;
+    ss << res;
+
+    // close connection
+    boost::system::error_code ec;
+    socket.shutdown(tcp::socket::shutdown_both, ec);
+
+    // not_connected is supposedly ok to ignore
+    if (ec && ec != boost::system::errc::not_connected)
+        throw std::runtime_error(ec.message());
+
+    return ss;
+}

src/utilhttp.h

@@ -0,0 +1,11 @@
+#ifndef UTILHTTP_H
+#define UTILHTTP_H
+
+#include <sstream>
+#include <string>
+
+std::stringstream http_get(const std::string &host,
+    const std::string &service /* aka port */,
+    const std::string &target /* ex: /index.html */);
+
+#endif