---
title: RequestHandleCacheKey
summary: 'An extension trait for RequestHandles that adds methods for controlling cache keys. # Stability'
url: https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/experimental/trait.RequestHandleCacheKey/
---

**Kind:** Trait  
**Module:** [experimental](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/experimental/)  
**Package:** fastly 0.13.1  
**Source:** https://docs.rs/crate/fastly/0.13.1/source/src/experimental.rs#203

```rust
pub trait RequestHandleCacheKey {
    // Required method
    fn set_cache_key(&mut self, key: impl AsRef<[u8]>);
}
```

An extension trait for [`RequestHandle`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.RequestHandle/)s that adds methods for controlling cache
keys.
## Stability

This is part of an experimental API that is subject to change or removal even in minor versions of
this crate.

## Methods

### set_cache_key

**Source:** https://docs.rs/crate/fastly/0.13.1/source/src/experimental.rs#206

```rust
fn set_cache_key(&mut self, key: impl AsRef<[u8]>)
```

See [`RequestHandle::set_cache_key()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.RequestHandle/#impl-RequestHandleCacheKey).
#### Stability

This is part of an experimental API that is subject to change or removal even in minor versions of
this crate.

**Parameters**

- `self`: `&mut Self`
- `key`: `impl AsRef<[u8]>`