Struct NonBlocking

pub struct NonBlocking { /* private fields */ }

A non-blocking writer.

While the line between “blocking” and “non-blocking” IO is fuzzy, writing to a file is typically considered to be a blocking operation. For an application whose Subscriber writes spans and events as they are emitted, an application might find the latency profile to be unacceptable. NonBlocking moves the writing out of an application’s data path by sending spans and events to a dedicated logging thread.

This struct implements MakeWriter from the tracing-subscriber crate. Therefore, it can be used with the tracing_subscriber::fmt module or with any other subscriber/layer implementation that uses the MakeWriter trait.

Implementations

impl NonBlocking

pub fn new<T: Write + Send + 'static>(writer: T) -> (NonBlocking, WorkerGuard)

Returns a new NonBlocking writer wrapping the provided writer.

The returned NonBlocking writer will have the default configuration values. Other configurations can be specified using the builder interface.

pub fn error_counter(&self) -> ErrorCounter

Returns a counter for the number of times logs where dropped. This will always return zero if NonBlocking is not lossy.

Trait Implementations

impl Clone for NonBlocking

fn clone(&self) -> NonBlocking

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for NonBlocking

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

Formats the value using the given formatter.

impl<'a> MakeWriter<'a> for NonBlocking

type Writer = NonBlocking

The concrete io::Write implementation returned by make_writer.

fn make_writer(&'a self) -> Self::Writer

Returns an instance of Writer.

fn make_writer_for(&'a self, meta: &Metadata<'_>) -> Self::Writer

Returns a Writer for writing data from the span or event described by the provided Metadata.

impl Write for NonBlocking

fn write(&mut self, buf: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_all(&mut self, buf: &[u8]) -> Result<()>

Attempts to write an entire buffer into this writer.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector #69941)

Determines if this Writer has an efficient write_vectored implementation.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored #70436)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.