From c57f97b8c1d97ee5d23a6cac4c84fe0af1a19b36 Mon Sep 17 00:00:00 2001
From: Marcelo Zimbres <mzimbres@gmail.com>
Date: Sat, 6 Aug 2022 23:12:32 +0200
Subject: [PATCH] Improvements in the examples.

---
 examples/chat_room.cpp              | 27 ++++++++---------
 examples/subscriber.cpp             |  4 +--
 examples/subscriber_sync.cpp        | 47 +++++++++++++++--------------
 include/aedis/experimental/sync.hpp | 15 +++++++++
 4 files changed, 54 insertions(+), 39 deletions(-)

diff --git a/examples/chat_room.cpp b/examples/chat_room.cpp
index 867f6f1a..789f7171 100644
--- a/examples/chat_room.cpp
+++ b/examples/chat_room.cpp
@@ -31,7 +31,7 @@ using response_type = std::vector<aedis::resp3::node<std::string>>;
 //
 // To see the message traffic.
 
-net::awaitable<void> reader(std::shared_ptr<connection> db)
+net::awaitable<void> subscriber(std::shared_ptr<connection> db)
 {
    request req;
    req.push("SUBSCRIBE", "chat-channel");
@@ -54,19 +54,14 @@ net::awaitable<void> reader(std::shared_ptr<connection> db)
 }
 
 net::awaitable<void>
-run(net::posix::stream_descriptor& in, std::shared_ptr<connection> db)
+publisher(net::posix::stream_descriptor& in, std::shared_ptr<connection> db)
 {
-   try {
-      for (std::string msg;;) {
-         std::size_t n = co_await net::async_read_until(in, net::dynamic_buffer(msg, 1024), "\n", net::use_awaitable);
-         request req;
-         req.push("PUBLISH", "chat-channel", msg);
-         co_await db->async_exec(req);
-         msg.erase(0, n);
-      }
-
-   } catch (std::exception const& e) {
-      std::cerr << "Error: " << e.what() << std::endl;
+   for (std::string msg;;) {
+      std::size_t n = co_await net::async_read_until(in, net::dynamic_buffer(msg, 1024), "\n", net::use_awaitable);
+      request req;
+      req.push("PUBLISH", "chat-channel", msg);
+      co_await db->async_exec(req);
+      msg.erase(0, n);
    }
 }
 
@@ -75,17 +70,19 @@ int main()
    try {
       net::io_context ioc{1};
       net::posix::stream_descriptor in{ioc, ::dup(STDIN_FILENO)};
+
       auto db = std::make_shared<connection>(ioc);
       db->get_config().enable_events = true;
-      co_spawn(ioc, run(in, db), net::detached);
-      co_spawn(ioc, reader(db), net::detached);
 
+      co_spawn(ioc, publisher(in, db), net::detached);
+      co_spawn(ioc, subscriber(db), net::detached);
       db->async_run([](auto ec) {
          std::cout << ec.message() << std::endl;
       });
 
       net::signal_set signals(ioc, SIGINT, SIGTERM);
       signals.async_wait([&](auto, auto){ ioc.stop(); });
+
       ioc.run();
    } catch (std::exception const& e) {
       std::cerr << e.what() << std::endl;
diff --git a/examples/subscriber.cpp b/examples/subscriber.cpp
index 4a33dfb7..062069f9 100644
--- a/examples/subscriber.cpp
+++ b/examples/subscriber.cpp
@@ -58,8 +58,8 @@ net::awaitable<void> receiver(std::shared_ptr<connection> db)
          break;
 
          case connection::event::hello:
-         // Subscribes to the channels again after stablishing a new
-         // connection.
+         // Subscribes to the channels when a new connection is
+         // stablished.
          co_await db->async_exec(req);
          break;
 
diff --git a/examples/subscriber_sync.cpp b/examples/subscriber_sync.cpp
index 450be56f..9dc23da8 100644
--- a/examples/subscriber_sync.cpp
+++ b/examples/subscriber_sync.cpp
@@ -24,6 +24,30 @@ using event = connection::event;
 
 // See subscriber.cpp for more info about how to run this example.
 
+void subscriber(connection& conn)
+{
+   request req;
+   req.push("SUBSCRIBE", "channel");
+
+   for (std::vector<node<std::string>> resp;;) {
+      auto const ev = receive_event(conn, aedis::adapt(resp));
+      switch (ev) {
+         case connection::event::push:
+         print_push(resp);
+         resp.clear();
+         break;
+
+         case connection::event::hello:
+         // Subscribes to the channels when a new connection is
+         // stablished.
+         exec(conn, req);
+         break;
+
+         default:;
+      }
+   }
+}
+
 int main()
 {
    try {
@@ -38,28 +62,7 @@ int main()
          ioc.run();
       }};
 
-      request req;
-      req.push("SUBSCRIBE", "channel");
-
-      for (std::vector<node<std::string>> resp;;) {
-         boost::system::error_code ec;
-         auto const ev = receive_event(conn, aedis::adapt(resp), ec);
-         switch (ev) {
-            case connection::event::push:
-            print_push(resp);
-            resp.clear();
-            break;
-
-            case connection::event::hello:
-            // Subscribes to the channels again after stablishing a
-            // new connection.
-            exec(conn, req);
-            break;
-
-            default:;
-         }
-      }
-
+      subscriber(conn);
       thread.join();
 
    } catch (std::exception const& e) {
diff --git a/include/aedis/experimental/sync.hpp b/include/aedis/experimental/sync.hpp
index debfd277..d24d906b 100644
--- a/include/aedis/experimental/sync.hpp
+++ b/include/aedis/experimental/sync.hpp
@@ -130,6 +130,21 @@ auto receive_event(
    return ev;
 }
 
+/// TODO
+template <
+   class Connection,
+   class ResponseAdapter = aedis::detail::response_traits<void>::adapter_type>
+auto receive_event(
+   Connection& conn,
+   ResponseAdapter adapter = aedis::adapt())
+{
+   boost::system::error_code ec;
+   auto const res = receive_event(conn, adapter, ec);
+   if (ec)
+      throw std::system_error(ec);
+   return res;
+}
+
 } // experimental
 } // aedis