Maintain keyexpr type in interceptors (#1851)

* Cache keyexpr as `OwnedKeyExpr` instead of `String`

* Rebase against main

* Fix test build

* Fix low pass interceptor

* Add `Resource::keyexpr`

* Clippy errors (1)

Author: fuzzypixelz

zenoh/src/net/routing/dispatcher/face.rs

@@ -42,16 +42,13 @@ use super::{
     resource::*,
     tables::TablesLock,
 };
-use crate::{
-    api::key_expr::KeyExpr,
-    net::{
-        primitives::{McastMux, Mux, Primitives},
-        routing::{
-            dispatcher::interests::finalize_pending_interests,
-            interceptor::{
-                EgressInterceptor, IngressInterceptor, InterceptorFactory, InterceptorTrait,
-                InterceptorsChain,
-            },
+use crate::net::{
+    primitives::{McastMux, Mux, Primitives},
+    routing::{
+        dispatcher::interests::finalize_pending_interests,
+        interceptor::{
+            EgressInterceptor, IngressInterceptor, InterceptorFactory, InterceptorTrait,
+            InterceptorsChain,
         },
     },
 };
@@ -157,8 +154,8 @@ impl FaceState {
             .map(|itor| itor.load())
             .and_then(|is| is.is_empty().not().then_some(is))
         {
-            if let Ok(expr) = KeyExpr::try_from(res.expr().to_string()) {
-                let cache = interceptor.compute_keyexpr_cache(&expr);
+            if let Some(expr) = res.keyexpr() {
+                let cache = interceptor.compute_keyexpr_cache(expr);
                 get_mut_unchecked(
                     get_mut_unchecked(res)
                         .session_ctxs
@@ -176,8 +173,8 @@ impl FaceState {
             .map(|mux| mux.interceptor.load())
             .and_then(|is| is.is_empty().not().then_some(is))
         {
-            if let Ok(expr) = KeyExpr::try_from(res.expr().to_string()) {
-                let cache = interceptor.compute_keyexpr_cache(&expr);
+            if let Some(expr) = res.keyexpr() {
+                let cache = interceptor.compute_keyexpr_cache(expr);
                 get_mut_unchecked(
                     get_mut_unchecked(res)
                         .session_ctxs
@@ -195,8 +192,8 @@ impl FaceState {
             .map(|mux| mux.interceptor.load())
             .and_then(|is| is.is_empty().not().then_some(is))
         {
-            if let Ok(expr) = KeyExpr::try_from(res.expr().to_string()) {
-                let cache = interceptor.compute_keyexpr_cache(&expr);
+            if let Some(expr) = res.keyexpr() {
+                let cache = interceptor.compute_keyexpr_cache(expr);
                 get_mut_unchecked(
                     get_mut_unchecked(res)
                         .session_ctxs

zenoh/src/net/routing/dispatcher/resource.rs

@@ -79,10 +79,7 @@ impl InterceptorCache {
     ) -> Option<InterceptorCacheValueType> {
         self.0
             .value(interceptor.version, || {
-                // Safety: resource expr is always a valid keyexpr
-                let ke = unsafe { keyexpr::from_str_unchecked(resource.expr()) };
-                let key_expr = ke.into();
-                interceptor.compute_keyexpr_cache(&key_expr)
+                interceptor.compute_keyexpr_cache(resource.keyexpr()?)
             })
             .ok()
     }
@@ -323,6 +320,15 @@ impl Resource {
         &self.expr
     }
 
+    pub fn keyexpr(&self) -> Option<&keyexpr> {
+        if self.parent.is_none() {
+            None
+        } else {
+            // SAFETY: non-root resources are valid keyexprs
+            unsafe { Some(keyexpr::from_str_unchecked(&self.expr)) }
+        }
+    }
+
     pub fn suffix(&self) -> &str {
         &self.expr[self.suffix..]
     }