Struct actix_rt::net::TcpListener [−][src]
pub struct TcpListener { /* fields omitted */ }
Expand description
A TCP socket server, listening for connections.
You can accept a new connection by using the accept
method. Alternatively TcpListener
implements the Stream
trait, which allows you to use the listener in places that want a
stream. The stream will never return None
and will also not yield the peer’s SocketAddr
structure. Iterating over
it is equivalent to calling accept in a loop.
Errors
Note that accepting a connection can lead to various errors and not all of them are necessarily fatal ‒ for example having too many open file descriptors or the other side closing the connection while it waits in an accept queue. These would terminate the stream if not handled in any way.
Examples
Using accept
:
use tokio::net::TcpListener;
use std::io;
async fn process_socket<T>(socket: T) {
// do work with socket here
}
#[tokio::main]
async fn main() -> io::Result<()> {
let mut listener = TcpListener::bind("127.0.0.1:8080").await?;
loop {
let (socket, _) = listener.accept().await?;
process_socket(socket).await;
}
}
Using impl Stream
:
use tokio::{net::TcpListener, stream::StreamExt};
#[tokio::main]
async fn main() {
let mut listener = TcpListener::bind("127.0.0.1:8080").await.unwrap();
while let Some(stream) = listener.next().await {
match stream {
Ok(stream) => {
println!("new client!");
}
Err(e) => { /* connection failed */ }
}
}
}
Implementations
Creates a new TcpListener, which will be bound to the specified address.
The returned listener is ready for accepting connections.
Binding with a port number of 0 will request that the OS assigns a port
to this listener. The port allocated can be queried via the local_addr
method.
The address type can be any implementor of the ToSocketAddrs
trait.
Note that strings only implement this trait when the dns
feature
is enabled, as strings may contain domain names that need to be resolved.
If addr
yields multiple addresses, bind will be attempted with each of
the addresses until one succeeds and returns the listener. If none of
the addresses succeed in creating a listener, the error returned from
the last attempt (the last address) is returned.
This function sets the SO_REUSEADDR
option on the socket.
Examples
use tokio::net::TcpListener;
use std::io;
#[tokio::main]
async fn main() -> io::Result<()> {
let listener = TcpListener::bind("127.0.0.1:2345").await?;
// use the listener
Ok(())
}
Without the dns
feature:
use tokio::net::TcpListener;
use std::net::Ipv4Addr;
use std::io;
#[tokio::main]
async fn main() -> io::Result<()> {
let listener = TcpListener::bind((Ipv4Addr::new(127, 0, 0, 1), 2345)).await?;
// use the listener
Ok(())
}
Accepts a new incoming connection from this listener.
This function will yield once a new TCP connection is established. When
established, the corresponding TcpStream
and the remote peer’s
address will be returned.
Examples
use tokio::net::TcpListener;
use std::io;
#[tokio::main]
async fn main() -> io::Result<()> {
let mut listener = TcpListener::bind("127.0.0.1:8080").await?;
match listener.accept().await {
Ok((_socket, addr)) => println!("new client: {:?}", addr),
Err(e) => println!("couldn't get client: {:?}", e),
}
Ok(())
}
pub fn poll_accept(
&mut self,
cx: &mut Context<'_>
) -> Poll<Result<(TcpStream, SocketAddr), Error>>
pub fn poll_accept(
&mut self,
cx: &mut Context<'_>
) -> Poll<Result<(TcpStream, SocketAddr), Error>>
Polls to accept a new incoming connection to this listener.
If there is no connection to accept, Poll::Pending
is returned and
the current task will be notified by a waker.
Creates a new TCP listener from the standard library’s TCP listener.
This method can be used when the Handle::tcp_listen
method isn’t
sufficient because perhaps some more configuration is needed in terms of
before the calls to bind
and listen
.
This API is typically paired with the net2
crate and the TcpBuilder
type to build up and customize a listener before it’s shipped off to the
backing event loop. This allows configuration of options like
SO_REUSEPORT
, binding to multiple addresses, etc.
The addr
argument here is one of the addresses that listener
is
bound to and the listener will only be guaranteed to accept connections
of the same address type currently.
The platform specific behavior of this function looks like:
-
On Unix, the socket is placed into nonblocking mode and connections can be accepted as normal
-
On Windows, the address is stored internally and all future accepts will only be for the same IP version as
addr
specified. That is, ifaddr
is an IPv4 address then all sockets accepted will be IPv4 as well (same for IPv6).
Examples
use std::error::Error;
use tokio::net::TcpListener;
#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
let std_listener = std::net::TcpListener::bind("127.0.0.1:0")?;
let listener = TcpListener::from_std(std_listener)?;
Ok(())
}
Panics
This function panics if thread-local runtime is not set.
The runtime is usually set implicitly when this function is called
from a future driven by a tokio runtime, otherwise runtime can be set
explicitly with Handle::enter
function.
Returns the local address that this listener is bound to.
This can be useful, for example, when binding to port 0 to figure out which port was actually bound.
Examples
use tokio::net::TcpListener;
use std::io;
use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4};
#[tokio::main]
async fn main() -> io::Result<()> {
let listener = TcpListener::bind("127.0.0.1:8080").await?;
assert_eq!(listener.local_addr()?,
SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080)));
Ok(())
}
Returns a stream over the connections being received on this listener.
Note that TcpListener
also directly implements Stream
.
The returned stream will never return None
and will also not yield the
peer’s SocketAddr
structure. Iterating over it is equivalent to
calling accept in a loop.
Errors
Note that accepting a connection can lead to various errors and not all of them are necessarily fatal ‒ for example having too many open file descriptors or the other side closing the connection while it waits in an accept queue. These would terminate the stream if not handled in any way.
Examples
use tokio::{net::TcpListener, stream::StreamExt};
#[tokio::main]
async fn main() {
let mut listener = TcpListener::bind("127.0.0.1:8080").await.unwrap();
let mut incoming = listener.incoming();
while let Some(stream) = incoming.next().await {
match stream {
Ok(stream) => {
println!("new client!");
}
Err(e) => { /* connection failed */ }
}
}
}
Gets the value of the IP_TTL
option for this socket.
For more information about this option, see set_ttl
.
Examples
use tokio::net::TcpListener;
use std::io;
#[tokio::main]
async fn main() -> io::Result<()> {
let listener = TcpListener::bind("127.0.0.1:0").await?;
listener.set_ttl(100).expect("could not set TTL");
assert_eq!(listener.ttl()?, 100);
Ok(())
}
Sets the value for the IP_TTL
option on this socket.
This value sets the time-to-live field that is used in every packet sent from this socket.
Examples
use tokio::net::TcpListener;
use std::io;
#[tokio::main]
async fn main() -> io::Result<()> {
let listener = TcpListener::bind("127.0.0.1:0").await?;
listener.set_ttl(100).expect("could not set TTL");
Ok(())
}
Trait Implementations
pub fn poll_next(
self: Pin<&mut TcpListener>,
cx: &mut Context<'_>
) -> Poll<Option<<TcpListener as Stream>::Item>>
pub fn poll_next(
self: Pin<&mut TcpListener>,
cx: &mut Context<'_>
) -> Poll<Option<<TcpListener as Stream>::Item>>
Attempt to pull out the next value of this stream, registering the
current task for wakeup if the value is not yet available, and returning
None
if the stream is exhausted. Read more
pub fn try_from(
stream: TcpListener
) -> Result<TcpListener, <TcpListener as TryFrom<TcpListener>>::Error>
pub fn try_from(
stream: TcpListener
) -> Result<TcpListener, <TcpListener as TryFrom<TcpListener>>::Error>
Consumes stream, returning the tokio I/O object.
This is equivalent to
TcpListener::from_std(stream)
.
Auto Trait Implementations
impl !RefUnwindSafe for TcpListener
impl Send for TcpListener
impl Sync for TcpListener
impl Unpin for TcpListener
impl !UnwindSafe for TcpListener
Blanket Implementations
Mutably borrows from an owned value. Read more
Creates a future that resolves to the next item in the stream. Read more
Maps this stream’s items to a different type, returning a new stream of the resulting type. Read more
Creates a stream which gives the current iteration count as well as the next value. Read more
Filters the values produced by this stream according to the provided asynchronous predicate. Read more
Filters the values produced by this stream while simultaneously mapping them to a different type according to the provided asynchronous closure. Read more
Computes from this stream’s items new items of a different type using an asynchronous closure. Read more
Transforms a stream into a collection, returning a future representing the result of that computation. Read more
Converts a stream of pairs into a future, which resolves to pair of containers. Read more
Concatenate all items of a stream into a single extendable destination, returning a future representing the end result. Read more
Drives the stream to completion, counting the number of items. Read more
Execute an accumulating asynchronous computation over a stream, collecting all the values into one final result. Read more
Execute predicate over asynchronous stream, and return true
if any element in stream satisfied a predicate. Read more
Execute predicate over asynchronous stream, and return true
if all element in stream satisfied a predicate. Read more
Flattens a stream of streams into just one continuous stream. Read more
Maps a stream like StreamExt::map
but flattens nested Stream
s. Read more
Combinator similar to StreamExt::fold
that holds internal state
and produces a new stream. Read more
Skip elements on this stream while the provided asynchronous predicate
resolves to true
. Read more
Take elements from this stream while the provided asynchronous predicate
resolves to true
. Read more
Take elements from this stream until the provided future resolves. Read more
Runs this stream to completion, executing the provided asynchronous closure for each element on the stream. Read more
Runs this stream to completion, executing the provided asynchronous closure for each element on the stream concurrently as elements become available. Read more
Creates a new stream of at most n
items of the underlying stream. Read more
Creates a new stream which skips n
items of the underlying stream. Read more
Catches unwinding panics while polling the stream. Read more
Wrap the stream in a Box, pinning it. Read more
Wrap the stream in a Box, pinning it. Read more
An adaptor for creating a buffered list of pending futures. Read more
An adaptor for creating a buffered list of pending futures (unordered). Read more
An adapter for zipping two streams together. Read more
Adapter for chaining two streams. Read more
An adaptor for chunking up items of the stream inside a vector. Read more
An adaptor for chunking up ready items of the stream inside a vector. Read more
A future that completes after the given stream has been fully processed into the sink and the sink has been flushed and closed. Read more
Splits this Stream + Sink
object into separate Sink
and Stream
objects. Read more
Do something with each item of this stream, afterwards passing it on. Read more
Wrap this stream in an Either
stream, making it the left-hand variant
of that Either
. Read more
Wrap this stream in an Either
stream, making it the right-hand variant
of that Either
. Read more
A convenience method for calling Stream::poll_next
on Unpin
stream types. Read more
Consumes and returns the next value in the stream or None
if the
stream is finished. Read more
Consumes and returns the next item in the stream. If an error is encountered before the next item, the error is returned instead. Read more
Maps this stream’s items to a different type, returning a new stream of the resulting type. Read more
Combine two streams into one by interleaving the output of both as it is produced. Read more
Filters the values produced by this stream according to the provided predicate. Read more
Filters the values produced by this stream while simultaneously mapping them to a different type according to the provided closure. Read more
Creates a new stream of at most n
items of the underlying stream. Read more
Take elements from this stream while the provided predicate
resolves to true
. Read more
Creates a new stream that will skip the n
first items of the
underlying stream. Read more
Skip elements from the underlying stream while the provided predicate
resolves to true
. Read more
Tests if every element of the stream matches a predicate. Read more
Tests if any element of the stream matches a predicate. Read more
Combine two streams into one by first returning all values from the first stream then all values from the second stream. Read more
A combinator that applies a function to every element in a stream producing a single, final value. Read more
Drain stream pushing all emitted values into a collection. Read more
Wraps the current stream in a new stream which converts the error type into the one provided. Read more
Wraps the current stream in a new stream which maps the success value using the provided closure. Read more
Wraps the current stream in a new stream which maps the error value using the provided closure. Read more
Chain on a computation for when a value is ready, passing the successful
results to the provided closure f
. Read more
Chain on a computation for when an error happens, passing the
erroneous result to the provided closure f
. Read more
Do something with the success value of this stream, afterwards passing it on. Read more
Do something with the error value of this stream, afterwards passing it on. Read more
Creates a future that attempts to resolve the next item in the stream. If an error is encountered before the next item, the error is returned instead. Read more
Attempts to run this stream to completion, executing the provided asynchronous closure for each element on the stream. Read more
Skip elements on this stream while the provided asynchronous predicate
resolves to true
. Read more
Take elements on this stream while the provided asynchronous predicate
resolves to true
. Read more
Attempts to run this stream to completion, executing the provided asynchronous closure for each element on the stream concurrently as elements become available, exiting as soon as an error occurs. Read more
Attempt to transform a stream into a collection, returning a future representing the result of that computation. Read more
An adaptor for chunking up successful items of the stream inside a vector. Read more
Attempt to filter the values produced by this stream according to the provided asynchronous closure. Read more
Attempt to filter the values produced by this stream while simultaneously mapping them to a different type according to the provided asynchronous closure. Read more
Flattens a stream of streams into just one continuous stream. Read more
Attempt to execute an accumulating asynchronous computation over a stream, collecting all the values into one final result. Read more
fn try_concat(self) -> TryConcat<Self> where
Self::Ok: Extend<<Self::Ok as IntoIterator>::Item>,
Self::Ok: IntoIterator,
Self::Ok: Default,
fn try_concat(self) -> TryConcat<Self> where
Self::Ok: Extend<<Self::Ok as IntoIterator>::Item>,
Self::Ok: IntoIterator,
Self::Ok: Default,
Attempt to concatenate all items of a stream into a single extendable destination, returning a future representing the end result. Read more
Attempt to execute several futures from a stream concurrently (unordered). Read more
Attempt to execute several futures from a stream concurrently. Read more
A convenience method for calling TryStream::try_poll_next
on Unpin
stream types. Read more