Struct Context 

pub struct Context { /* private fields */ }

Runtime capabilities and supervision context for the current task.

Ordinary children run on the pool, including those spawned by dedicated and blocking tasks. Task factories run on their caller, while ordinary futures run on the pool and can move between its workers, as can resources and pending I/O and sleep futures.

Registrations stay on their original worker. Closing that worker causes unresolved I/O futures to fail and unresolved sleeps to panic when polled. Pool workers close only at shutdown, after every pool task has been dropped, while dedicated and blocking tasks may still run. Detached sync completion handles can be awaited on any thread.

Trait Implementations

impl Clock for Context

fn current(&self) -> SystemTime

Returns the current time.

fn sleep( &self, duration: Duration, ) -> impl Future<Output = ()> + Send + 'static + use<>

Sleep for the given duration.

fn sleep_until( &self, deadline: SystemTime, ) -> impl Future<Output = ()> + Send + 'static + use<>

Sleep until the given deadline.

fn timeout<F, T>( &self, duration: Duration, future: F, ) -> impl Future<Output = Result<T, Error>> + Send + '_

where F: Future<Output = T> + Send + 'static, T: Send + 'static,

Await a future with a timeout, returning Error::Timeout if it expires.

impl Clock for Context

type Instant = SystemTime

A measurement of a monotonically increasing clock.

fn now(&self) -> Self::Instant

Returns a measurement of the clock.

impl Metrics for Context

fn register<N: Into<String>, H: Into<String>, M: Metric>( &self, name: N, help: H, metric: M, ) -> Registered<M>

Register a metric with the runtime.

fn encode(&self) -> String

Encode all metrics into a buffer.

impl Network for Context

type Listener = <Network<Network> as Network>::Listener

The type of Listener that’s returned when binding to a socket. Accepting a connection returns a Sink and Stream which are defined by the Listener and used to send and receive data over the connection.

async fn bind(&self, socket: SocketAddr) -> Result<Self::Listener, Error>

Bind to the given socket address.

async fn dial( &self, socket: SocketAddr, ) -> Result<(SinkOf<Self>, StreamOf<Self>), Error>

Dial the given socket address.

impl ReasonablyRealtime for Context

fn reference_point(&self) -> Self::Instant

Returns a reference point at the start of an operation.

impl Resolver for Context

async fn resolve(&self, host: &str) -> Result<Vec<IpAddr>, Error>

Resolve a hostname to IP addresses.

impl Spawner for Context

fn dedicated(self) -> Self

Return a Spawner that runs the next task on a dedicated thread when the runtime supports it.

fn shared(self, blocking: bool) -> Self

Return a Spawner that schedules the next task onto the runtime’s shared executor.

fn spawn<F, Fut, T>(self, f: F) -> Handle<T>

where F: FnOnce(Self) -> Fut + Send + 'static, Fut: Future<Output = T> + Send + 'static, T: Send + 'static,

Spawn a task with the current context.

async fn stop(self, value: i32, timeout: Option<Duration>) -> Result<(), Error>

Signals the runtime to stop execution and waits for all outstanding tasks to perform any required cleanup and exit.

fn stopped(&self) -> Signal

Returns an instance of a signal::Signal that resolves when Spawner::stop is called by any task.

impl Storage for Context

type Blob = <Storage<Storage> as Storage>::Blob

The readable/writeable storage buffer that can be opened by this Storage.

async fn open_versioned( &self, partition: &str, name: &[u8], versions: RangeInclusive<BlobVersion>, ) -> Result<(Self::Blob, u64, BlobVersion), Error>

Open an existing blob in a given partition or create a new one, returning the blob and its length.

async fn remove( &self, partition: &str, name: Option<&[u8]>, ) -> Result<(), Error>

Remove a blob from a given partition.

async fn scan(&self, partition: &str) -> Result<Vec<Vec<u8>>, Error>

Return all blobs in a given partition.

fn open( &self, partition: &str, name: &[u8], ) -> impl Future<Output = Result<(Self::Blob, u64), Error>> + Send

Storage::open_versioned with DEFAULT_BLOB_VERSION as the only value in the versions range. The blob version is omitted from the return value.

impl Strategizer for Context

fn strategy(&self, parallelism: NonZeroUsize) -> Rayon

Returns a new Rayon strategy with the requested parallelism.

impl Supervisor for Context

fn child(&self, label: &'static str) -> Self

Create a named child context with a new supervision-tree node.

fn with_attribute(self, key: &'static str, value: impl Display) -> Self

Add a key-value attribute to this context’s identity.

fn name(&self) -> Name

Return the current label prefix and attributes.

impl TryCryptoRng for Context

impl TryRng for Context

type Error = !

The type returned in the event of a RNG error.

fn try_next_u32(&mut self) -> Result<u32, Self::Error>

Return the next random u32.

fn try_next_u64(&mut self) -> Result<u64, Self::Error>

Return the next random u64.

fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Self::Error>

Fill dst entirely with random data.