1 files changed, 99 insertions, 0 deletions

diff --git a/server/src/log.cpp b/server/src/log.cpp
new file mode 100644
index 0000000..7fe725f
--- /dev/null
+++ b/server/src/log.cpp
@@ -0,0 +1,99 @@
+module routemon:log$impl;
+
+import :log;
+
+namespace routemon::log {
+
+auto operator<<(std::ostream& os, level lvl) -> std::ostream&
+{
+  switch (lvl)
+  {
+  case level::debug:
+    os << "dbg";
+    break;
+  case level::info:
+    os << "inf";
+    break;
+  case level::warn:
+    os << "wrn";
+    break;
+  case level::error:
+    os << "err";
+    break;
+  }
+  return os;
+}
+
+sink::sink(enum level lvl) : lvl_{lvl} {}
+
+auto sink::level() const -> enum level { return lvl_; }
+
+auto sink::set_level(enum level lvl) -> void { lvl_ = lvl; }
+
+auto sink::write(tmp_message msg) -> void
+{
+  auto sos = std::osyncstream{os_};
+  sos << "[" << msg.lvl;
+  if (!msg.component.empty())
+    sos << " " << msg.component;
+  sos << "] " << msg.txt;
+  for (auto const& [k, v] : msg.attrs)
+    sos << " " << k << "=" << std::quoted(v);
+  sos << '\n';
+}
+
+auto make_sink(level lvl) -> std::shared_ptr<sink>
+{
+  return std::shared_ptr<sink>{new sink{lvl}};
+}
+
+auto logger::log_at(log::level lvl, std::string_view fmt, std::format_args args)
+    -> logger&
+{
+  if (sink_->level() <= lvl)
+    sink_->write(
+        sink::tmp_message{
+          .lvl = lvl,
+          .component = component_,
+          .txt = std::vformat(fmt, args),
+          .attrs = attrs_,
+        });
+  return *this;
+}
+
+logger::logger(std::shared_ptr<sink> const& sink) : sink_{sink}
+{
+  if (!sink)
+  {
+    throw std::invalid_argument{"logger sink may not be null"};
+  }
+}
+
+auto logger::sub(std::string_view component) const -> logger
+{
+  auto l = *this;
+  if (l.component_.empty())
+  {
+    l.component_ = component;
+  }
+  else
+  {
+    l.component_ += ".";
+    l.component_ += component;
+  }
+  return l;
+}
+
+auto logger::with(std::string const& k, std::string&& v) const -> logger
+{
+  auto l = *this;
+  l.attrs_[k] = std::move(v);
+  return l;
+}
+
+auto logger::with(std::string const& k, std::string_view v) const -> logger
+{
+  return with(k, std::string{v});
+}
+
+} // namespace routemon::log