--- title: PendingRequestHandle summary: A handle to a pending asynchronous request returned by RequestHandle::sendasync() or RequestHandle::sendasync_streaming(). url: https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.PendingRequestHandle/ --- **Kind:** Struct **Module:** [handle](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/) **Package:** fastly 0.13.1 **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#22 ```rust pub struct PendingRequestHandle { /* private fields */ } ``` A handle to a pending asynchronous request returned by [`RequestHandle::send_async()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.RequestHandle/#method-send_async) or [`RequestHandle::send_async_streaming()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.RequestHandle/#method-send_async_streaming). A handle can be evaluated using [`PendingRequestHandle::poll()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.PendingRequestHandle/#method-poll), [`PendingRequestHandle::wait()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.PendingRequestHandle/#method-wait), or [`select_handles()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/fn.select_handles/). It can also be discarded if the request was sent for effects it might have, and the response is unimportant. ## Methods ### append_response_header **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#93 ```rust fn append_response_header(&self, name: impl ToHeaderName, value: impl ToHeaderValue, target: PendingResponseKind) ``` Append a header on the `Response` once it is ready, leaving any existing entries of the same name in place. **Parameters** - `self`: `&Self` - `name`: `impl ToHeaderName` - `value`: `impl ToHeaderValue` - `target`: `PendingResponseKind` ### as_u32 **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#78 ```rust fn as_u32(&self) -> u32 ``` Get the underlying representation of the handle. This should only be used when calling the raw ABI directly, and care should be taken not to reuse or alias handle values. **Parameters** - `self`: `&Self` **Returns** `u32` ### poll **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#197 ```rust fn poll(self) -> PollHandleResult ``` Try to get the result of a pending request without blocking. This function returns immediately with a [`PollHandleResult`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/enum.PollHandleResult/); if you want to block until a result is ready, use [`wait()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.PendingRequestHandle/#method-wait). **Parameters** - `self`: `Self` **Returns** `PollHandleResult` ### remove_response_header **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#148 ```rust fn remove_response_header(&self, name: impl ToHeaderName, target: PendingResponseKind) ``` Remove a header from the `Response` once it is ready. **Parameters** - `self`: `&Self` - `name`: `impl ToHeaderName` - `target`: `PendingResponseKind` ### send_to_client **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#187 ```rust fn send_to_client(self) ``` Move processing of the [PendingRequestHandle](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.PendingRequestHandle/) to the background and forward its eventual response to the downstream client. If an error is encountered while sending the request (for example, a [SendErrorCause::ConnectionRefused](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/http/request/enum.SendErrorCause/) due to the server being unavailable), then an appropriate 5XX response will be sent instead. Using this allows the sandbox to terminate early so that its resources may be freed up for other incoming requests. **Parameters** - `self`: `Self` ### set_response_header **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#121 ```rust fn set_response_header(&self, name: impl ToHeaderName, value: impl ToHeaderValue, target: PendingResponseKind) ``` Set a header on the `Response` once it is ready, replacing any existing entries of the same name. **Parameters** - `self`: `&Self` - `name`: `impl ToHeaderName` - `value`: `impl ToHeaderValue` - `target`: `PendingResponseKind` ### wait **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#245 ```rust fn wait(self) -> Result<(ResponseHandle, BodyHandle), SendErrorCause> ``` Block until the result of a pending request is ready. If you want check whether the result is ready without blocking, use [`poll()`](https://www.fastly.com/documentation/reference/compute/sdks/rust/fastly/handle/struct.PendingRequestHandle/#method-poll). **Parameters** - `self`: `Self` **Returns** `Result<(ResponseHandle, BodyHandle), SendErrorCause>` ## Trait implementations ### impl Debug for PendingRequestHandle #### fmt **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#19 ```rust fn fmt(&self, f: &mut Formatter<'_>) -> Result ``` **Parameters** - `self`: `&Self` - `f`: `&mut $crate::fmt::Formatter` **Returns** `$crate::fmt::Result` ### impl From for PendingRequestHandle #### from **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#27 ```rust fn from(pr: PendingRequest) -> Self ``` **Parameters** - `pr`: `PendingRequest` **Returns** `Self` ### impl Hash for PendingRequestHandle #### hash **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#20 ```rust fn hash<__H: Hasher>(&self, state: &mut __H) ``` **Parameters** - `self`: `&Self` - `state`: `&mut __H` ### impl PartialEq for PendingRequestHandle #### eq **Source:** https://docs.rs/crate/fastly/0.13.1/source/src/http/request/pending/handle.rs#20 ```rust fn eq(&self, other: &Self) -> bool ``` **Parameters** - `self`: `&Self` - `other`: `&Self` **Returns** `bool` ## Auto trait implementations - `Freeze` - `RefUnwindSafe` - `Send` - `Sync` - `Unpin` - `UnsafeUnpin` - `UnwindSafe` ## Blanket implementations - `Any` - `Borrow` - `BorrowMut` - `Downcast` - `DowncastSync` - `Equivalent` - `ErasedDestructor` - `From` - `Into` - `IntoEither` - `Same` - `TryFrom` - `TryInto`