fix: address code review feedback (log warnings, redact Redis URL credentials, add doc comment)

Agent-Logs-Url: https://github.com/katanemo/plano/sessions/6a75240b-4578-409d-b8c7-eff47dba8a03

Co-authored-by: adilhafeez <13196462+adilhafeez@users.noreply.github.com>

crates/brightstaff/src/main.rs

@@ -53,6 +53,29 @@ fn parse_semver(version: &str) -> (u32, u32, u32) {
     (major, minor, patch)
 }
 
+/// Redact the userinfo (username:password) from a URL string for safe logging.
+///
+/// `redis://user:secret@localhost:6379` → `redis://<redacted>@localhost:6379`
+///
+/// URLs without credentials are returned unchanged.
+fn redact_url_credentials(url: &str) -> String {
+    // Find "://" and then look for "@" before any "/" in the authority.
+    if let Some(after_scheme) = url.find("://").map(|i| i + 3) {
+        let authority = &url[after_scheme..];
+        if let Some(at_pos) = authority.find('@') {
+            // Only redact if the '@' comes before any path separator.
+            if !authority[..at_pos].contains('/') {
+                return format!(
+                    "{}<redacted>@{}",
+                    &url[..after_scheme],
+                    &authority[at_pos + 1..]
+                );
+            }
+        }
+    }
+    url.to_string()
+}
+
 /// CORS pre-flight response for the models endpoint.
 fn cors_preflight() -> Result<Response<BoxBody<Bytes, hyper::Error>>, hyper::Error> {
     let mut response = Response::new(empty());
@@ -412,8 +435,10 @@ async fn init_session_cache(
                 .and_then(|c| c.url.as_deref())
                 .ok_or("session_cache.url is required for redis session cache")?;
 
+            // Log only the host portion to avoid exposing credentials in plain-text logs.
+            let display_url = redact_url_credentials(url);
             debug!(url = %url, "redis session cache connection");
-            info!(cache_type = "redis", url = %url, "initializing session cache");
+            info!(cache_type = "redis", url = %display_url, "initializing session cache");
 
             Arc::new(
                 RedisSessionCache::new(url, ttl_secs)

crates/brightstaff/src/router/session_cache.rs

@@ -6,7 +6,7 @@ use std::collections::HashMap;
 use std::sync::Arc;
 use std::time::Duration;
 use tokio::sync::RwLock;
-use tracing::info;
+use tracing::{debug, info, warn};
 
 /// A cached routing decision stored by session ID.
 #[derive(Clone, Debug, Serialize, Deserialize)]
@@ -156,16 +156,27 @@ impl SessionCache for RedisSessionCache {
     }
 
     async fn put(&self, session_id: &str, route: CachedRoute) {
-        let Ok(json) = serde_json::to_string(&route) else {
-            return;
+        let json = match serde_json::to_string(&route) {
+            Ok(j) => j,
+            Err(e) => {
+                warn!(session_id = %session_id, error = %e, "failed to serialize CachedRoute for Redis");
+                return;
+            }
         };
         let mut conn = self.conn.write().await;
-        let _: redis::RedisResult<()> = conn.set_ex(session_id, json, self.ttl_secs).await;
+        if let Err(e) = conn
+            .set_ex::<_, _, ()>(session_id, json, self.ttl_secs)
+            .await
+        {
+            warn!(session_id = %session_id, error = %e, "failed to write session cache entry to Redis");
+        }
     }
 
     async fn remove(&self, session_id: &str) {
         let mut conn = self.conn.write().await;
-        let _: redis::RedisResult<()> = conn.del(session_id).await;
+        if let Err(e) = conn.del::<_, ()>(session_id).await {
+            debug!(session_id = %session_id, error = %e, "failed to delete session cache entry from Redis");
+        }
     }
 
     /// Redis handles expiry natively — this is a no-op.

crates/common/src/configuration.rs

@@ -18,6 +18,8 @@ pub enum SessionCacheType {
 pub struct SessionCacheConfig {
     #[serde(rename = "type")]
     pub cache_type: SessionCacheType,
+    /// Redis connection URL (e.g. `redis://localhost:6379`).
+    /// Required when `cache_type` is [`SessionCacheType::Redis`]; ignored otherwise.
     pub url: Option<String>,
 }