1 files changed, 101 insertions, 0 deletions
diff --git a/src/log_bridge.rs b/src/log_bridge.rs
new file mode 100644
index 0000000..35bcb01
--- /dev/null
+++ b/src/log_bridge.rs
@@ -0,0 +1,101 @@
+// TODO Temporary file until we have a better logging setup for slog
+
+use slog::{Drain, KV};
+use std::fmt::{self, Arguments, Write};
+
+pub struct LogBridge<T>(pub T);
+
+impl<T: log::Log> Drain for LogBridge<T> {
+    type Ok = ();
+    type Err = slog::Error;
+
+    fn log(&self, record: &slog::Record, kvs: &slog::OwnedKVList) -> Result<(), Self::Err> {
+        let mut target = record.tag();
+        if target.is_empty() {
+            target = record.module();
+        }
+
+        let lazy = LazyLog::new(record, kvs);
+
+        self.0.log(
+            &log::Record::builder()
+                .args(format_args!("{}", lazy))
+                .level(level_to_log(record.level()))
+                .target(target)
+                .module_path_static(Some(record.module()))
+                .file_static(Some(record.file()))
+                .line(Some(record.line()))
+                .build(),
+        );
+
+        Ok(())
+    }
+
+    fn is_enabled(&self, level: slog::Level) -> bool {
+        let meta = log::Metadata::builder().level(level_to_log(level)).build();
+
+        self.0.enabled(&meta)
+    }
+}
+
+fn level_to_log(level: slog::Level) -> log::Level {
+    match level {
+        slog::Level::Critical | slog::Level::Error => log::Level::Error,
+        slog::Level::Warning => log::Level::Warn,
+        slog::Level::Info => log::Level::Info,
+        slog::Level::Debug => log::Level::Debug,
+        slog::Level::Trace => log::Level::Trace,
+    }
+}
+
+struct LazyLog<'a> {
+    record: &'a slog::Record<'a>,
+    kvs: &'a slog::OwnedKVList,
+}
+
+impl<'a> LazyLog<'a> {
+    fn new(record: &'a slog::Record, kvs: &'a slog::OwnedKVList) -> Self {
+        LazyLog { record, kvs }
+    }
+}
+
+impl<'a> fmt::Display for LazyLog<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.record.msg())?;
+
+        let mut ser = StringSerializer::new();
+
+        self.kvs
+            .serialize(self.record, &mut ser)
+            .map_err(|_| fmt::Error)?;
+        self.record
+            .kv()
+            .serialize(self.record, &mut ser)
+            .map_err(|_| fmt::Error)?;
+
+        write!(f, "{}", ser.finish())
+    }
+}
+
+struct StringSerializer {
+    inner: String,
+}
+
+impl StringSerializer {
+    fn new() -> Self {
+        StringSerializer {
+            inner: String::new(),
+        }
+    }
+
+    fn finish(self) -> String {
+        self.inner
+    }
+}
+
+impl slog::Serializer for StringSerializer {
+    fn emit_arguments(&mut self, key: slog::Key, value: &Arguments) -> slog::Result {
+        write!(self.inner, ", {}: {}", key, value)?;
+        Ok(())
+    }
+}