feat: Promote rpxy-lib/sticky-cookie to top-level feature

.. and fix compile warnings when disabled

rpxy-bin/Cargo.toml

@@ -13,10 +13,10 @@ publish.workspace = true
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-# default = ["http3-quinn", "cache", "rustls-backend", "acme", "post-quantum"]
-# default = ["http3-s2n", "cache", "rustls-backend", "acme", "post-quantum"]
-default = ["http3-quinn", "cache", "rustls-backend", "acme"]
-# default = ["http3-s2n", "cache", "rustls-backend", "acme"]
+# default = ["http3-quinn", "cache", "rustls-backend", "acme", "sticky-cookie", "post-quantum"]
+# default = ["http3-s2n", "cache", "rustls-backend", "acme", "sticky-cookie", "post-quantum"]
+default = ["http3-quinn", "cache", "rustls-backend", "acme", "sticky-cookie"]
+# default = ["http3-s2n", "cache", "rustls-backend", "acme", "sticky-cookie"]
 http3-quinn = ["rpxy-lib/http3-quinn"]
 http3-s2n = ["rpxy-lib/http3-s2n"]
 native-tls-backend = ["rpxy-lib/native-tls-backend"]
@@ -25,11 +25,10 @@ webpki-roots = ["rpxy-lib/webpki-roots"]
 cache = ["rpxy-lib/cache"]
 acme = ["rpxy-lib/acme", "rpxy-acme"]
 post-quantum = ["rpxy-lib/post-quantum"]
+sticky-cookie = ["rpxy-lib/sticky-cookie"]
 
 [dependencies]
-rpxy-lib = { path = "../rpxy-lib/", default-features = false, features = [
-  "sticky-cookie",
-] }
+rpxy-lib = { path = "../rpxy-lib/", default-features = false }
 
 mimalloc = { version = "*", default-features = false }
 anyhow = "1.0.91"

rpxy-lib/src/backend/load_balance/load_balance_main.rs

@@ -131,6 +131,4 @@ impl LoadBalance {
 pub struct LoadBalanceContext {
   #[cfg(feature = "sticky-cookie")]
   pub sticky_cookie: StickyCookie,
-  #[cfg(not(feature = "sticky-cookie"))]
-  pub sticky_cookie: (),
 }

rpxy-lib/src/backend/load_balance/mod.rs

@@ -4,6 +4,7 @@ mod load_balance_sticky;
 #[cfg(feature = "sticky-cookie")]
 mod sticky_cookie;
 
+#[cfg(feature = "sticky-cookie")]
 use super::upstream::Upstream;
 use thiserror::Error;
 
@@ -16,6 +17,7 @@ pub use load_balance_sticky::LoadBalanceStickyBuilder;
 pub use sticky_cookie::{StickyCookie, StickyCookieValue};
 
 /// Result type for load balancing
+#[cfg(feature = "sticky-cookie")]
 type LoadBalanceResult<T> = std::result::Result<T, LoadBalanceError>;
 /// Describes things that can go wrong in the Load Balance
 #[derive(Debug, Error)]

rpxy-lib/src/message_handler/handler_main.rs

@@ -6,7 +6,7 @@ use super::{
   utils_request::InspectParseHost,
 };
 use crate::{
-  backend::{BackendAppManager, LoadBalanceContext},
+  backend::BackendAppManager,
   error::*,
   forwarder::{ForwardRequest, Forwarder},
   globals::Globals,
@@ -25,7 +25,7 @@ use tokio::io::copy_bidirectional;
 /// Context object to handle sticky cookies at HTTP message handler
 pub(super) struct HandlerContext {
   #[cfg(feature = "sticky-cookie")]
-  pub(super) context_lb: Option<LoadBalanceContext>,
+  pub(super) context_lb: Option<crate::backend::LoadBalanceContext>,
   #[cfg(not(feature = "sticky-cookie"))]
   pub(super) context_lb: Option<()>,
 }

rpxy-lib/src/message_handler/utils_headers.rs

@@ -3,7 +3,7 @@ use crate::{
   backend::{UpstreamCandidates, UpstreamOption},
   log::*,
 };
-use anyhow::{anyhow, ensure, Result};
+use anyhow::{anyhow, Result};
 use bytes::BufMut;
 use http::{header, HeaderMap, HeaderName, HeaderValue, Uri};
 use std::{borrow::Cow, net::SocketAddr};
@@ -22,6 +22,8 @@ pub(super) fn takeout_sticky_cookie_lb_context(
   headers: &mut HeaderMap,
   expected_cookie_name: &str,
 ) -> Result<Option<LoadBalanceContext>> {
+  use anyhow::ensure;
+
   let mut headers_clone = headers.clone();
 
   match headers_clone.entry(header::COOKIE) {