Struct erkpht_tower::builder::ServiceBuilder

pub struct ServiceBuilder<L> { /* fields omitted */ }

Declaratively construct Service values.

ServiceBuilder provides a builder-like interface for composing layers to be applied to a Service.

Service

A Service is a trait representing an asynchronous function of a request to a response. It is similar to async fn(Request) -> Result<Response, Error>.

A Service is typically bound to a single transport, such as a TCP connection. It defines how all inbound or outbound requests are handled by that connection.

Order

The order in which layers are added impacts how requests are handled. Layers that are added first will be called with the request first. The argument to service will be last to see the request.

#[cfg(all(feature = "buffer", feature = "limit"))]
ServiceBuilder::new()
    .buffer(100)
    .concurrency_limit(10)
    .service(svc)

In the above example, the buffer layer receives the request first followed by concurrency_limit. buffer enables up to 100 request to be in-flight on top of the requests that have already been forwarded to the next layer. Combined with concurrency_limit, this allows up to 110 requests to be in-flight.

#[cfg(all(feature = "buffer", feature = "limit"))]
ServiceBuilder::new()
    .concurrency_limit(10)
    .buffer(100)
    .service(svc)

The above example is similar, but the order of layers is reversed. Now, concurrency_limit applies first and only allows 10 requests to be in-flight total.

Examples

A Service stack with a single layer:

#[cfg(feature = "limit")]
ServiceBuilder::new()
    .concurrency_limit(5)
    .service(svc);

A Service stack with multiple layers that contain rate limiting, in-flight request limits, and a channel-backed, clonable Service:

#[cfg(all(feature = "buffer", feature = "limit"))]
ServiceBuilder::new()
    .buffer(5)
    .concurrency_limit(5)
    .rate_limit(5, Duration::from_secs(1))
    .service(svc);

Methods

impl ServiceBuilder<Identity>

pub fn new() -> Self

Create a new ServiceBuilder.

impl<L> ServiceBuilder<L>

pub fn layer<T>(self, layer: T) -> ServiceBuilder<Stack<T, L>>

Add a new layer T into the ServiceBuilder.

pub fn into_inner(self) -> L

Obtains the underlying Layer implementation.

pub fn service<S>(self, service: S) -> L::Service where
    L: Layer<S>, 

Wrap the service S with the layers.

Trait Implementations

impl<L: Clone> Clone for ServiceBuilder<L>

fn clone(&self) -> ServiceBuilder<L>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<L: Debug> Debug for ServiceBuilder<L>

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.