refactor(http1): use LOG constant only with tracing

Author: seanmonstar

src/proto/h1/mod.rs

@@ -30,6 +30,7 @@ cfg_server! {
 pub(crate) trait Http1Transaction {
     type Incoming;
     type Outgoing: Default;
+    #[cfg(feature = "tracing")]
     const LOG: &'static str;
     fn parse(bytes: &mut BytesMut, ctx: ParseContext<'_>) -> ParseResult<Self::Incoming>;
     fn encode(enc: Encode<'_, Self::Outgoing>, dst: &mut Vec<u8>) -> crate::Result<Encoder>;

src/proto/h1/role.rs

@@ -104,6 +104,7 @@ pub(crate) enum Server {}
 impl Http1Transaction for Server {
     type Incoming = RequestLine;
     type Outgoing = StatusCode;
+    #[cfg(feature = "tracing")]
     const LOG: &'static str = "{role=server}";
 
     fn parse(buf: &mut BytesMut, ctx: ParseContext<'_>) -> ParseResult<RequestLine> {
@@ -964,6 +965,7 @@ trait HeaderNameWriter {
 impl Http1Transaction for Client {
     type Incoming = StatusCode;
     type Outgoing = RequestLine;
+    #[cfg(feature = "tracing")]
     const LOG: &'static str = "{role=client}";
 
     fn parse(buf: &mut BytesMut, ctx: ParseContext<'_>) -> ParseResult<StatusCode> {