simplelog 0.12.2

A simple and easy-to-use logging facility for Rust's log crate
Documentation
use crate::config::{TargetPadding, TimeFormat};
use crate::{Config, LevelPadding, ThreadLogMode, ThreadPadding};
use log::{LevelFilter, Record};
use std::io::{Error, Write};
use std::thread;
#[cfg(all(feature = "termcolor", feature = "ansi_term"))]
use termcolor::Color;

#[cfg(all(feature = "termcolor", feature = "ansi_term"))]
pub fn termcolor_to_ansiterm(color: &Color) -> Option<ansi_term::Color> {
    match color {
        Color::Black => Some(ansi_term::Color::Black),
        Color::Red => Some(ansi_term::Color::Red),
        Color::Green => Some(ansi_term::Color::Green),
        Color::Yellow => Some(ansi_term::Color::Yellow),
        Color::Blue => Some(ansi_term::Color::Blue),
        Color::Magenta => Some(ansi_term::Color::Purple),
        Color::Cyan => Some(ansi_term::Color::Cyan),
        Color::White => Some(ansi_term::Color::White),
        _ => None,
    }
}

#[inline(always)]
pub fn try_log<W>(config: &Config, record: &Record<'_>, write: &mut W) -> Result<(), Error>
where
    W: Write + Sized,
{
    if should_skip(config, record) {
        return Ok(());
    }

    if config.time <= record.level() && config.time != LevelFilter::Off {
        write_time(write, config)?;
    }

    if config.level <= record.level() && config.level != LevelFilter::Off {
        write_level(record, write, config)?;
    }

    if config.thread <= record.level() && config.thread != LevelFilter::Off {
        match config.thread_log_mode {
            ThreadLogMode::IDs => {
                write_thread_id(write, config)?;
            }
            ThreadLogMode::Names | ThreadLogMode::Both => {
                write_thread_name(write, config)?;
            }
        }
    }

    if config.target <= record.level() && config.target != LevelFilter::Off {
        write_target(record, write, config)?;
    }

    if config.location <= record.level() && config.location != LevelFilter::Off {
        write_location(record, write)?;
    }

    write_args(record, write)
}

#[inline(always)]
pub fn write_time<W>(write: &mut W, config: &Config) -> Result<(), Error>
where
    W: Write + Sized,
{
    use time::error::Format;
    use time::format_description::well_known::*;

    let time = time::OffsetDateTime::now_utc().to_offset(config.time_offset);
    let res = match config.time_format {
        TimeFormat::Rfc2822 => time.format_into(write, &Rfc2822),
        TimeFormat::Rfc3339 => time.format_into(write, &Rfc3339),
        TimeFormat::Custom(format) => time.format_into(write, &format),
    };
    match res {
        Err(Format::StdIo(err)) => return Err(err),
        Err(err) => panic!("Invalid time format: {}", err),
        _ => {}
    };

    write!(write, " ")?;
    Ok(())
}

#[inline(always)]
pub fn write_level<W>(record: &Record<'_>, write: &mut W, config: &Config) -> Result<(), Error>
where
    W: Write + Sized,
{
    #[cfg(all(feature = "termcolor", feature = "ansi_term"))]
    let color = match &config.level_color[record.level() as usize] {
        Some(termcolor) => {
            if config.write_log_enable_colors {
                termcolor_to_ansiterm(termcolor)
            } else {
                None
            }
        }
        None => None,
    };

    let level = match config.level_padding {
        LevelPadding::Left => format!("[{: >5}]", record.level()),
        LevelPadding::Right => format!("[{: <5}]", record.level()),
        LevelPadding::Off => format!("[{}]", record.level()),
    };

    #[cfg(all(feature = "termcolor", feature = "ansi_term"))]
    match color {
        Some(c) => write!(write, "{} ", c.paint(level))?,
        None => write!(write, "{} ", level)?,
    };

    #[cfg(not(feature = "ansi_term"))]
    write!(write, "{} ", level)?;

    Ok(())
}

#[inline(always)]
pub fn write_target<W>(record: &Record<'_>, write: &mut W, config: &Config) -> Result<(), Error>
where
    W: Write + Sized,
{
    // dbg!(&config.target_padding);
    match config.target_padding {
        TargetPadding::Left(pad) => {
            write!(
                write,
                "{target:>pad$}: ",
                pad = pad,
                target = record.target()
            )?;
        }
        TargetPadding::Right(pad) => {
            write!(
                write,
                "{target:<pad$}: ",
                pad = pad,
                target = record.target()
            )?;
        }
        TargetPadding::Off => {
            write!(write, "{}: ", record.target())?;
        }
    }

    Ok(())
}

#[inline(always)]
pub fn write_location<W>(record: &Record<'_>, write: &mut W) -> Result<(), Error>
where
    W: Write + Sized,
{
    let file = record.file().unwrap_or("<unknown>");
    if let Some(line) = record.line() {
        write!(write, "[{}:{}] ", file, line)?;
    } else {
        write!(write, "[{}:<unknown>] ", file)?;
    }
    Ok(())
}

pub fn write_thread_name<W>(write: &mut W, config: &Config) -> Result<(), Error>
where
    W: Write + Sized,
{
    if let Some(name) = thread::current().name() {
        match config.thread_padding {
            ThreadPadding::Left { 0: qty } => {
                write!(write, "({name:>0$}) ", qty, name = name)?;
            }
            ThreadPadding::Right { 0: qty } => {
                write!(write, "({name:<0$}) ", qty, name = name)?;
            }
            ThreadPadding::Off => {
                write!(write, "({}) ", name)?;
            }
        }
    } else if config.thread_log_mode == ThreadLogMode::Both {
        write_thread_id(write, config)?;
    }

    Ok(())
}

pub fn write_thread_id<W>(write: &mut W, config: &Config) -> Result<(), Error>
where
    W: Write + Sized,
{
    let id = format!("{:?}", thread::current().id());
    let id = id.replace("ThreadId(", "");
    let id = id.replace(")", "");
    match config.thread_padding {
        ThreadPadding::Left { 0: qty } => {
            write!(write, "({id:>0$}) ", qty, id = id)?;
        }
        ThreadPadding::Right { 0: qty } => {
            write!(write, "({id:<0$}) ", qty, id = id)?;
        }
        ThreadPadding::Off => {
            write!(write, "({}) ", id)?;
        }
    }
    Ok(())
}

#[inline(always)]
pub fn write_args<W>(record: &Record<'_>, write: &mut W) -> Result<(), Error>
where
    W: Write + Sized,
{
    writeln!(write, "{}", record.args())?;
    Ok(())
}

#[inline(always)]
pub fn should_skip(config: &Config, record: &Record<'_>) -> bool {
    // If a module path and allowed list are available
    match (record.target(), &*config.filter_allow) {
        (path, allowed) if !allowed.is_empty() => {
            // Check that the module path matches at least one allow filter
            if !allowed.iter().any(|v| path.starts_with(&**v)) {
                // If not, skip any further writing
                return true;
            }
        }
        _ => {}
    }

    // If a module path and ignore list are available
    match (record.target(), &*config.filter_ignore) {
        (path, ignore) if !ignore.is_empty() => {
            // Check that the module path does not match any ignore filters
            if ignore.iter().any(|v| path.starts_with(&**v)) {
                // If not, skip any further writing
                return true;
            }
        }
        _ => {}
    }

    false
}