Crate async_logger

Asyncronous logger.

AsyncLoggerNB is implementation of asyncronous logger that allows writing arbitrary u8 slices to a memory buffer, and then send the buffer to a writer.

NB at the end of AsyncLoggerNB stands for non-blocking. Implementation allows adding messages to a buffer without locking the buffer which prevents other threads from writing. AsyncLoggerNB uses pair of fixed size buffers; while one buffer is being written by the multiple threads, the second is being proccessed by the single writer thread. Blocking appears when buffers change their roles. Thus, this implementation is applicable in situation of small (compared to the size of buffer) writes by multiple threads running on multiple cpu cores with high concurrency of writes.

AsyncLoggerNB can accept any writer implementation of Writer trait. This package includes FileWriter that writes data to a file. You can create your own implementation of the Writer trait as well.

Implementation of log facade based on this asyncronous logger is available as separate crate async_logger_log. Please refer to async_logger_log crate documentation for more info and examples.

Examples

use async_logger::FileWriter;
use async_logger::AsyncLoggerNB;
use std::{thread, sync::Arc};

let writer = FileWriter::new("/tmp").expect("Failed to create file writer");

let logger = Arc::new(AsyncLoggerNB::new(Box::new(writer), 1024)
    .expect("Failed to create new async logger"));

let write_line = "Hello, world!\n";
 
let logger_c = logger.clone();

let handle = thread::spawn(move || {

    logger_c.write_slice(write_line.as_bytes()).unwrap();
    logger_c.write_slice(write_line.as_bytes()).unwrap();
    logger_c.flush();

    logger_c.write_slice(write_line.as_bytes()).unwrap();

});

handle.join().expect("Failed on thread join");

match Arc::try_unwrap(logger) {
    Ok(logger) => logger.terminate(),
    Err(_) => panic!("Failed to terminate logger because it is still in use"),
};

Structs

AsyncLoggerNB	Logger with non-blocking async processing.
Error	Errors returned by the crate functions.
FileWriter	Writer to a file.

Enums

ErrorKind

Error kinds.

Traits

Writer

Writer performs data processing of a fully filled buffer.