Add try_get_with_entry to have access to whether an entry is fresh or not

[calavera]

👋 I have some code that requires to know whether an entry is fresh from the cache or not.

I decided to expose that functionality in a new public function try_get_with_entry. I'll appreciate it if this code could make it back into upstream. I think it's pretty trivial to maintain since it's just the code in try_get_with without the map exposed in a public function.

---

Summary by CodeRabbit

• New Features

  • Added a cache query that returns full entry objects (value plus metadata) for advanced caching scenarios.

• Refactor

  • Updated the existing value-only retrieval to delegate to the new entry-aware flow, simplifying control flow and making initialization and hashing paths consistent.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: c6ae000d-becb-4aa1-82ae-2667a778dcbb

📥 Commits

Reviewing files that changed from the base of the PR and between 863392b and 6faed13.

📒 Files selected for processing (1)

• src/future/cache.rs

🚧 Files skipped from review as they are similar to previous changes (1)

• src/future/cache.rs

---

📝 Walkthrough

Walkthrough

Added try_get_with_entry, an async method that returns Entry<K, V> (with init metadata) and refactored try_get_with to delegate to it and return only the value. Explicit generic where-clauses for F and E were added to try_get_with.

Changes

Cohort / File(s)	Summary
Cache Entry Accessor src/future/cache.rs	Added pub async fn try_get_with_entry<F, E>(&self, key: K, init: F) -> Result<Entry<K, V>, Arc<E>>; refactored pub async fn try_get_with<F, E>(&self, key: K, init: F) -> Result<V, Arc<E>> to call try_get_with_entry(...).await.map(Entry::into_value); introduced explicit bounds F: Future<Output = Result<V, E>> and E: Send + Sync + 'static.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐇 I hopped into cache, nose twitching with glee,

I found an Entry hiding a secret for me,
One method now yields, the other just peeks,
Values and metadata, tidy techniques,
🥕 code crumbs scattered, a rabbit's small feat.

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately summarizes the main change: adding a new try_get_with_entry method that allows callers to determine whether a cache entry is fresh or not.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

src/future/cache.rs (1)

1305-1333: ⚠️ Potential issue | 🔴 Critical

try_get_with_entry can return an Entry that panics on key()

At Line 1331, need_key is false, so this new public API can return Entry<K, V> with no key materialized. Calling Entry::key() then panics (Bug: Key is None), which is a correctness issue for the exposed method.

🔧 Suggested fix

 pub async fn try_get_with<F, E>(&self, key: K, init: F) -> Result<V, Arc<E>>
 where
     F: Future<Output = Result<V, E>>,
     E: Send + Sync + 'static,
 {
-    self.try_get_with_entry(key, init).await.map(Entry::into_value)
+    futures_util::pin_mut!(init);
+    let hash = self.base.hash(&key);
+    let key = Arc::new(key);
+    self.get_or_try_insert_with_hash_and_fun(key, hash, init, false)
+        .await
+        .map(Entry::into_value)
 }
 
 pub async fn try_get_with_entry<F, E>(&self, key: K, init: F) -> Result<Entry<K, V>, Arc<E>>
 where
     F: Future<Output = Result<V, E>>,
     E: Send + Sync + 'static,
 {
     futures_util::pin_mut!(init);
     let hash = self.base.hash(&key);
     let key = Arc::new(key);
-    self.get_or_try_insert_with_hash_and_fun(key, hash, init, false)
+    self.get_or_try_insert_with_hash_and_fun(key, hash, init, true)
         .await
 }

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@src/future/cache.rs` around lines 1305 - 1333, The public method
try_get_with_entry currently calls get_or_try_insert_with_hash_and_fun with
need_key set to false, which can return an Entry lacking the key and cause
Entry::key() to panic; change the call in try_get_with_entry to request the key
(set need_key = true) so the returned Entry always contains the key
materialized, ensuring Entry::key() is safe for callers (adjust
get_or_try_insert_with_hash_and_fun signature/usage if needed to accept the true
flag).

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Outside diff comments:
In `@src/future/cache.rs`:
- Around line 1305-1333: The public method try_get_with_entry currently calls
get_or_try_insert_with_hash_and_fun with need_key set to false, which can return
an Entry lacking the key and cause Entry::key() to panic; change the call in
try_get_with_entry to request the key (set need_key = true) so the returned
Entry always contains the key materialized, ensuring Entry::key() is safe for
callers (adjust get_or_try_insert_with_hash_and_fun signature/usage if needed to
accept the true flag).

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 75eaad1c-ac86-4633-b64c-7fed5144cd04

📥 Commits

Reviewing files that changed from the base of the PR and between 7006d8c and 863392b.

📒 Files selected for processing (1)

• src/future/cache.rs