tauri-plugin-log 2.9.0

Configurable logging for your Tauri app.
Documentation
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// Copyright 2019-2023 Tauri Programme within The Commons Conservancy
// SPDX-License-Identifier: Apache-2.0
// SPDX-License-Identifier: MIT

//! Logging for Tauri applications.

#![doc(
    html_logo_url = "https://github.com/tauri-apps/tauri/raw/dev/app-icon.png",
    html_favicon_url = "https://github.com/tauri-apps/tauri/raw/dev/app-icon.png"
)]

use fern::{Filter, FormatCallback};
use log::{LevelFilter, Record};
use serde::Serialize;
use serde_repr::{Deserialize_repr, Serialize_repr};
use std::borrow::Cow;
use std::fs::OpenOptions;
use std::io::Write;
use std::{
    fmt::Arguments,
    fs::{self, File},
    iter::FromIterator,
    path::{Path, PathBuf},
};
use tauri::{
    plugin::{self, TauriPlugin},
    Manager, Runtime,
};
use tauri::{AppHandle, Emitter};
use time::{macros::format_description, OffsetDateTime};

pub use fern;
pub use log;

mod commands;

pub const WEBVIEW_TARGET: &str = "webview";

#[cfg(target_os = "ios")]
mod ios {
    swift_rs::swift!(pub fn tauri_log(
      level: u8, message: *const std::ffi::c_void
    ));
}

const DEFAULT_MAX_FILE_SIZE: u64 = 40_000;
const DEFAULT_ROTATION_STRATEGY: RotationStrategy = RotationStrategy::KeepOne;
const DEFAULT_TIMEZONE_STRATEGY: TimezoneStrategy = TimezoneStrategy::UseUtc;
const DEFAULT_FILE_OPEN_STRATEGY: FileOpenStrategy = FileOpenStrategy::Append;
const DEFAULT_LOG_TARGETS: [Target; 2] = [
    Target::new(TargetKind::Stdout),
    Target::new(TargetKind::LogDir { file_name: None }),
];
const LOG_DATE_FORMAT: &[time::format_description::FormatItem<'_>] =
    format_description!("[year]-[month]-[day]_[hour]-[minute]-[second]");

#[derive(Debug, thiserror::Error)]
pub enum Error {
    #[error(transparent)]
    Tauri(#[from] tauri::Error),
    #[error(transparent)]
    Io(#[from] std::io::Error),
    #[error(transparent)]
    TimeFormat(#[from] time::error::Format),
    #[error(transparent)]
    InvalidFormatDescription(#[from] time::error::InvalidFormatDescription),
    #[error("Internal logger disabled and cannot be acquired or attached")]
    LoggerNotInitialized,
}

/// An enum representing the available verbosity levels of the logger.
///
/// It is very similar to the [`log::Level`], but serializes to unsigned ints instead of strings.
#[derive(Debug, Clone, Deserialize_repr, Serialize_repr)]
#[repr(u16)]
pub enum LogLevel {
    /// The "trace" level.
    ///
    /// Designates very low priority, often extremely verbose, information.
    Trace = 1,
    /// The "debug" level.
    ///
    /// Designates lower priority information.
    Debug,
    /// The "info" level.
    ///
    /// Designates useful information.
    Info,
    /// The "warn" level.
    ///
    /// Designates hazardous situations.
    Warn,
    /// The "error" level.
    ///
    /// Designates very serious errors.
    Error,
}

impl From<LogLevel> for log::Level {
    fn from(log_level: LogLevel) -> Self {
        match log_level {
            LogLevel::Trace => log::Level::Trace,
            LogLevel::Debug => log::Level::Debug,
            LogLevel::Info => log::Level::Info,
            LogLevel::Warn => log::Level::Warn,
            LogLevel::Error => log::Level::Error,
        }
    }
}

impl From<log::Level> for LogLevel {
    fn from(log_level: log::Level) -> Self {
        match log_level {
            log::Level::Trace => LogLevel::Trace,
            log::Level::Debug => LogLevel::Debug,
            log::Level::Info => LogLevel::Info,
            log::Level::Warn => LogLevel::Warn,
            log::Level::Error => LogLevel::Error,
        }
    }
}

#[derive(Debug, Clone)]
pub enum RotationStrategy {
    /// Will keep all the logs, renaming them to include the date.
    KeepAll,
    /// Will only keep the most recent log up to its maximal size.
    KeepOne,
    /// Will keep some of the most recent logs, renaming them to include the date.
    KeepSome(usize),
}

#[derive(Debug, Clone)]
pub enum TimezoneStrategy {
    UseUtc,
    UseLocal,
}

impl TimezoneStrategy {
    pub fn get_now(&self) -> OffsetDateTime {
        match self {
            TimezoneStrategy::UseUtc => OffsetDateTime::now_utc(),
            TimezoneStrategy::UseLocal => {
                OffsetDateTime::now_local().unwrap_or_else(|_| OffsetDateTime::now_utc())
            } // Fallback to UTC since Rust cannot determine local timezone
        }
    }
}

#[derive(Debug, Clone, PartialEq)]
pub enum FileOpenStrategy {
    /// Open existing file from last session and append, if any.
    Append,
    /// Create a new file on each session start, rotating the last session if any.
    Rotate,
}

/// A custom log writer that rotates the log file when it exceeds specified size.
struct RotatingFile {
    dir: PathBuf,
    file_name: String,
    path: PathBuf,
    /// Maximum file size before rotating in bytes
    max_size: u64,
    /// Current file size in bytes
    current_size: u64,
    rotation_strategy: RotationStrategy,
    timezone_strategy: TimezoneStrategy,
    file_open_strategy: FileOpenStrategy,
    inner: Option<File>,
    buffer: Vec<u8>,
}

impl RotatingFile {
    pub fn new(
        dir: impl AsRef<Path>,
        file_name: String,
        max_size: u64,
        rotation_strategy: RotationStrategy,
        timezone_strategy: TimezoneStrategy,
        file_open_strategy: FileOpenStrategy,
    ) -> Result<Self, Error> {
        let dir = dir.as_ref().to_path_buf();
        let path = dir.join(&file_name).with_extension("log");

        let mut rotator = Self {
            dir,
            file_name,
            path,
            max_size,
            current_size: 0,
            rotation_strategy,
            timezone_strategy,
            file_open_strategy,
            inner: None,
            buffer: Vec::new(),
        };

        rotator.open_file()?;
        if rotator.current_size >= rotator.max_size
            || (rotator.current_size > 0 && rotator.file_open_strategy == FileOpenStrategy::Rotate)
        {
            rotator.rotate()?;
        }
        if let RotationStrategy::KeepSome(keep_count) = rotator.rotation_strategy {
            rotator.remove_old_files(keep_count)?;
        }

        Ok(rotator)
    }

    fn open_file(&mut self) -> Result<(), Error> {
        let file = OpenOptions::new()
            .create(true)
            .append(true)
            .open(&self.path)?;
        self.current_size = file.metadata()?.len();
        self.inner = Some(file);
        Ok(())
    }

    fn rotate(&mut self) -> Result<(), Error> {
        if let Some(mut file) = self.inner.take() {
            let _ = file.flush();
        }
        if self.path.exists() {
            match self.rotation_strategy {
                RotationStrategy::KeepAll => {
                    self.rename_file_to_dated()?;
                }
                RotationStrategy::KeepSome(keep_count) => {
                    // remove_old_files excludes the active file.
                    // So we need to keep (keep_count - 1) archived files to make room for the one we are about to archive.
                    self.remove_old_files(keep_count - 1)?;
                    self.rename_file_to_dated()?;
                }
                RotationStrategy::KeepOne => {
                    fs::remove_file(&self.path)?;
                }
            }
        }
        self.open_file()?;
        Ok(())
    }

    /// Remove old log files until the number of old log files is equal to the keep_count,
    /// the current active log file is not included in the keep_count.
    fn remove_old_files(&self, keep_count: usize) -> Result<(), Error> {
        let mut files = fs::read_dir(&self.dir)?
            .filter_map(|entry| {
                let entry = entry.ok()?;
                let path = entry.path();
                let old_file_name = path.file_name()?.to_string_lossy().into_owned();
                if old_file_name.starts_with(&self.file_name)
                  // exclude the current active file
                  && old_file_name != format!("{}.log", self.file_name)
                {
                    let date = old_file_name
                        .strip_prefix(&self.file_name)?
                        .strip_prefix("_")?
                        .strip_suffix(".log")?;
                    Some((path, date.to_string()))
                } else {
                    None
                }
            })
            .collect::<Vec<_>>();

        files.sort_by(|a, b| a.1.cmp(&b.1));

        if files.len() > keep_count {
            let files_to_remove = files.len() - keep_count;
            for (old_log_path, _) in files.iter().take(files_to_remove) {
                fs::remove_file(old_log_path)?;
            }
        }
        Ok(())
    }

    fn rename_file_to_dated(&self) -> Result<(), Error> {
        let to = self.dir.join(format!(
            "{}_{}.log",
            self.file_name,
            self.timezone_strategy
                .get_now()
                .format(LOG_DATE_FORMAT)
                .unwrap(),
        ));
        if to.is_file() {
            // designated rotated log file name already exists
            // highly unlikely but defensively handle anyway by adding .bak to filename
            let mut to_bak = to.clone();
            to_bak.set_file_name(format!(
                "{}.bak",
                to_bak.file_name().unwrap().to_string_lossy()
            ));
            fs::rename(&to, to_bak)?;
        }
        fs::rename(&self.path, &to)?;
        Ok(())
    }
}

impl Write for RotatingFile {
    fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
        self.buffer.extend_from_slice(buf);
        Ok(buf.len())
    }

    fn flush(&mut self) -> std::io::Result<()> {
        if self.buffer.is_empty() {
            return Ok(());
        }
        if self.inner.is_none() {
            self.open_file().map_err(std::io::Error::other)?;
        }

        if self.current_size != 0 && self.current_size + (self.buffer.len() as u64) > self.max_size
        {
            self.rotate().map_err(std::io::Error::other)?;
        }

        if let Some(file) = self.inner.as_mut() {
            file.write_all(&self.buffer)?;
            self.current_size += self.buffer.len() as u64;
            file.flush()?;
        }
        self.buffer.clear();
        Ok(())
    }
}

#[derive(Debug, Serialize, Clone)]
struct RecordPayload {
    message: String,
    level: LogLevel,
}

/// An enum representing the available targets of the logger.
pub enum TargetKind {
    /// Print logs to stdout.
    Stdout,
    /// Print logs to stderr.
    Stderr,
    /// Write logs to the given directory.
    ///
    /// The plugin will ensure the directory exists before writing logs.
    Folder {
        path: PathBuf,
        file_name: Option<String>,
    },
    /// Write logs to the OS specific logs directory.
    ///
    /// ### Platform-specific
    ///
    /// |Platform   | Value                                                                                     | Example                                                     |
    /// | --------- | ----------------------------------------------------------------------------------------- | ----------------------------------------------------------- |
    /// | Linux     | `$XDG_DATA_HOME/{bundleIdentifier}/logs` or `$HOME/.local/share/{bundleIdentifier}/logs`  | `/home/alice/.local/share/com.tauri.dev/logs`               |
    /// | macOS/iOS | `{homeDir}/Library/Logs/{bundleIdentifier}`                                               | `/Users/Alice/Library/Logs/com.tauri.dev`                   |
    /// | Windows   | `{FOLDERID_LocalAppData}/{bundleIdentifier}/logs`                                         | `C:\Users\Alice\AppData\Local\com.tauri.dev\logs`           |
    /// | Android   | `{ConfigDir}/logs`                                                                        | `/data/data/com.tauri.dev/files/logs`                       |
    LogDir { file_name: Option<String> },
    /// Forward logs to the webview (via the `log://log` event).
    ///
    /// This requires the webview to subscribe to log events, via this plugins `attachConsole` function.
    Webview,
    /// Send logs to a [`fern::Dispatch`]
    ///
    /// You can use this to construct arbitrary log targets.
    Dispatch(fern::Dispatch),
}

type Formatter = dyn Fn(FormatCallback, &Arguments, &Record) + Send + Sync + 'static;

/// A log target.
pub struct Target {
    kind: TargetKind,
    filters: Vec<Box<Filter>>,
    formatter: Option<Box<Formatter>>,
}

impl Target {
    #[inline]
    pub const fn new(kind: TargetKind) -> Self {
        Self {
            kind,
            filters: Vec::new(),
            formatter: None,
        }
    }

    #[inline]
    pub fn filter<F>(mut self, filter: F) -> Self
    where
        F: Fn(&log::Metadata) -> bool + Send + Sync + 'static,
    {
        self.filters.push(Box::new(filter));
        self
    }

    #[inline]
    pub fn format<F>(mut self, formatter: F) -> Self
    where
        F: Fn(FormatCallback, &Arguments, &Record) + Send + Sync + 'static,
    {
        self.formatter.replace(Box::new(formatter));
        self
    }
}

pub struct Builder {
    dispatch: fern::Dispatch,
    rotation_strategy: RotationStrategy,
    timezone_strategy: TimezoneStrategy,
    file_open_strategy: FileOpenStrategy,
    max_file_size: u128,
    targets: Vec<Target>,
    is_skip_logger: bool,
}

impl Default for Builder {
    fn default() -> Self {
        #[cfg(desktop)]
        let format = format_description!("[[[year]-[month]-[day]][[[hour]:[minute]:[second]]");
        let dispatch = fern::Dispatch::new().format(move |out, message, record| {
            out.finish(
                #[cfg(mobile)]
                format_args!("[{}] {}", record.target(), message),
                #[cfg(desktop)]
                format_args!(
                    "{}[{}][{}] {}",
                    DEFAULT_TIMEZONE_STRATEGY.get_now().format(&format).unwrap(),
                    record.target(),
                    record.level(),
                    message
                ),
            )
        });
        Self {
            dispatch,
            rotation_strategy: DEFAULT_ROTATION_STRATEGY,
            timezone_strategy: DEFAULT_TIMEZONE_STRATEGY,
            file_open_strategy: DEFAULT_FILE_OPEN_STRATEGY,
            max_file_size: DEFAULT_MAX_FILE_SIZE as u128,
            targets: DEFAULT_LOG_TARGETS.into(),
            is_skip_logger: false,
        }
    }
}

impl Builder {
    pub fn new() -> Self {
        Default::default()
    }

    /// Sets the [`RotationStrategy`].
    ///
    /// Default is [`RotationStrategy::KeepOne`]
    pub fn rotation_strategy(mut self, rotation_strategy: RotationStrategy) -> Self {
        self.rotation_strategy = rotation_strategy;
        self
    }

    /// Sets the [`TimezoneStrategy`].
    /// Calling this method overrides the format set in [`Self::format`].
    ///
    /// Default is [`TimezoneStrategy::UseUtc`]
    pub fn timezone_strategy(mut self, timezone_strategy: TimezoneStrategy) -> Self {
        self.timezone_strategy = timezone_strategy.clone();

        let format = format_description!("[[[year]-[month]-[day]][[[hour]:[minute]:[second]]");
        self.dispatch = self.dispatch.format(move |out, message, record| {
            out.finish(format_args!(
                "{}[{}][{}] {}",
                timezone_strategy.get_now().format(&format).unwrap(),
                record.level(),
                record.target(),
                message
            ))
        });
        self
    }

    /// Sets the strategy to open the log file.
    ///
    /// The default is [`FileOpenStrategy::Append`].
    pub fn file_open_strategy(mut self, file_open_strategy: FileOpenStrategy) -> Self {
        self.file_open_strategy = file_open_strategy;
        self
    }

    /// Sets the maximum file size in bytes for log rotation.
    ///
    /// Values larger than [`u64::MAX`] will be clamped to [`u64::MAX`].
    /// In v3, this parameter will be changed to `u64`.
    ///
    /// Default is `40_000`
    pub fn max_file_size(mut self, max_file_size: u128) -> Self {
        self.max_file_size = max_file_size.min(u64::MAX as u128);
        self
    }

    /// Clears the format so that only the message is logged.
    ///
    /// e.g. `log::info!("message")` will log out `message`
    pub fn clear_format(mut self) -> Self {
        self.dispatch = self.dispatch.format(|out, message, _record| {
            out.finish(format_args!("{message}"));
        });
        self
    }

    /// Sets the formatter of this dispatch. The closure should accept a
    /// callback, a message and a log record, and write the resulting
    /// format to the writer.
    ///
    /// The log record is passed for completeness, but the `args()` method of
    /// the record should be ignored, and the [`std::fmt::Arguments`] given
    /// should be used instead. `record.args()` may be used to retrieve the
    /// _original_ log message, but in order to allow for true log
    /// chaining, formatters should use the given message instead whenever
    /// including the message in the output.
    ///
    /// To avoid all allocation of intermediate results, the formatter is
    /// "completed" by calling a callback, which then calls the rest of the
    /// logging chain with the new formatted message. The callback object keeps
    /// track of if it was called or not via a stack boolean as well, so if
    /// you don't use `out.finish` the log message will continue down
    /// the logger chain unformatted.
    ///
    /// Example usage:
    ///
    /// ```
    /// tauri_plugin_log::Builder::new()
    ///     .format(|out, message, record| {
    ///         out.finish(format_args!(
    ///             "[{} {}] {}",
    ///             record.level(),
    ///             record.target(),
    ///             message
    ///         ))
    ///     });
    /// ```
    pub fn format<F>(mut self, formatter: F) -> Self
    where
        F: Fn(FormatCallback, &Arguments, &Record) + Sync + Send + 'static,
    {
        self.dispatch = self.dispatch.format(formatter);
        self
    }

    /// Sets the overarching level filter for this logger.
    /// All messages not already filtered by something set by [`Self::level_for`] will be affected.
    ///
    /// All messages filtered will be discarded if less severe than the given level.
    ///
    /// Default level is [`log::LevelFilter::Trace`].
    pub fn level(mut self, level_filter: impl Into<LevelFilter>) -> Self {
        self.dispatch = self.dispatch.level(level_filter.into());
        self
    }

    /// Sets a per-target log level filter. Default target for log messages is
    /// `crate_name::module_name` or
    /// `crate_name` for logs in the crate root. Targets can also be set with
    /// `info!(target: "target-name", ...)`.
    ///
    /// For each log record fern will first try to match the most specific
    /// level_for, and then progressively more general ones until either a
    /// matching level is found, or the default level is used.
    ///
    /// For example, a log for the target `hyper::http::h1` will first test a
    /// level_for for `hyper::http::h1`, then for `hyper::http`, then for
    /// `hyper`, then use the default level.
    ///
    /// Examples:
    ///
    /// A program wants to include a lot of debugging output, but the library
    /// "hyper" is known to work well, so debug output from it should be
    /// excluded:
    ///
    /// ```
    /// # fn main() {
    /// tauri_plugin_log::Builder::new()
    ///     .level(log::LevelFilter::Trace)
    ///     .level_for("hyper", log::LevelFilter::Info)
    ///     # ;
    /// # }
    /// ```
    pub fn level_for(mut self, module: impl Into<Cow<'static, str>>, level: LevelFilter) -> Self {
        self.dispatch = self.dispatch.level_for(module, level);
        self
    }

    /// Adds a custom filter which can reject messages passing through this logger.
    ///
    /// [`Self::level`] and [`Self::level_for`] are preferred if applicable.
    ///
    /// Example usage:
    ///
    /// ```
    /// # fn main() {
    /// tauri_plugin_log::Builder::new()
    ///     .level(log::LevelFilter::Info)
    ///     .filter(|metadata| {
    ///         // Reject messages with the `Error` log level.
    ///         metadata.level() != log::LevelFilter::Error
    ///     })
    /// # }
    pub fn filter<F>(mut self, filter: F) -> Self
    where
        F: Fn(&log::Metadata) -> bool + Send + Sync + 'static,
    {
        self.dispatch = self.dispatch.filter(filter);
        self
    }

    /// Removes all targets. Useful to ignore the default targets and reconfigure them.
    pub fn clear_targets(mut self) -> Self {
        self.targets.clear();
        self
    }

    /// Adds a log target to the logger.
    ///
    /// ```rust
    /// use tauri_plugin_log::{Target, TargetKind};
    /// tauri_plugin_log::Builder::new()
    ///     .target(Target::new(TargetKind::Webview));
    /// ```
    ///
    /// The default targets are
    ///
    /// ```rust
    /// # use tauri_plugin_log::{Target, TargetKind, Builder};
    /// # Builder::new()
    /// #     .targets(
    /// [
    ///     Target::new(TargetKind::Stdout),
    ///     Target::new(TargetKind::LogDir { file_name: None }),
    /// ]
    /// #      );
    /// ```
    pub fn target(mut self, target: Target) -> Self {
        self.targets.push(target);
        self
    }

    /// Skip the creation and global registration of a logger
    ///
    /// If you wish to use your own global logger, you must call `skip_logger` so that the plugin does not attempt to set a second global logger. In this configuration, no logger will be created and the plugin's `log` command will rely on the result of `log::logger()`. You will be responsible for configuring the logger yourself and any included targets will be ignored. If ever initializing the plugin multiple times, such as if registering the plugin while testing, call this method to avoid panicking when registering multiple loggers. For interacting with `tracing`, you can leverage the `tracing-log` logger to forward logs to `tracing` or enable the `tracing` feature for this plugin to emit events directly to the tracing system. Both scenarios require calling this method.
    /// ```rust
    /// static LOGGER: SimpleLogger = SimpleLogger;
    ///
    /// log::set_logger(&SimpleLogger)?;
    /// log::set_max_level(LevelFilter::Info);
    /// tauri_plugin_log::Builder::new()
    ///     .skip_logger();
    /// ```
    pub fn skip_logger(mut self) -> Self {
        self.is_skip_logger = true;
        self
    }

    /// Replaces the targets of the logger.
    ///
    /// ```rust
    /// use tauri_plugin_log::{Target, TargetKind, WEBVIEW_TARGET};
    /// tauri_plugin_log::Builder::new()
    ///     .targets([
    ///         Target::new(TargetKind::Webview),
    ///         Target::new(TargetKind::LogDir { file_name: Some("webview".into()) }).filter(|metadata| metadata.target().starts_with(WEBVIEW_TARGET)),
    ///         Target::new(TargetKind::LogDir { file_name: Some("rust".into()) }).filter(|metadata| !metadata.target().starts_with(WEBVIEW_TARGET)),
    ///     ]);
    /// ```
    ///
    /// The default targets are
    ///
    /// ```rust
    /// # use tauri_plugin_log::{Target, TargetKind, Builder};
    /// # Builder::new()
    /// #     .targets(
    /// [
    ///     Target::new(TargetKind::Stdout),
    ///     Target::new(TargetKind::LogDir { file_name: None }),
    /// ]
    /// #      );
    /// ```
    pub fn targets(mut self, targets: impl IntoIterator<Item = Target>) -> Self {
        self.targets = Vec::from_iter(targets);
        self
    }

    #[cfg(feature = "colored")]
    pub fn with_colors(self, colors: fern::colors::ColoredLevelConfig) -> Self {
        let format = format_description!("[[[year]-[month]-[day]][[[hour]:[minute]:[second]]");

        let timezone_strategy = self.timezone_strategy.clone();
        self.format(move |out, message, record| {
            out.finish(format_args!(
                "{}[{}][{}] {}",
                timezone_strategy.get_now().format(&format).unwrap(),
                colors.color(record.level()),
                record.target(),
                message
            ))
        })
    }

    fn acquire_logger<R: Runtime>(
        app_handle: &AppHandle<R>,
        mut dispatch: fern::Dispatch,
        rotation_strategy: RotationStrategy,
        timezone_strategy: TimezoneStrategy,
        file_open_strategy: FileOpenStrategy,
        max_file_size: u64,
        targets: Vec<Target>,
    ) -> Result<(log::LevelFilter, Box<dyn log::Log>), Error> {
        let app_name = &app_handle.package_info().name;

        // setup targets
        for target in targets {
            let mut target_dispatch = fern::Dispatch::new();
            for filter in target.filters {
                target_dispatch = target_dispatch.filter(filter);
            }
            if let Some(formatter) = target.formatter {
                target_dispatch = target_dispatch.format(formatter);
            }

            let logger = match target.kind {
                #[cfg(target_os = "android")]
                TargetKind::Stdout | TargetKind::Stderr => fern::Output::call(android_logger::log),
                #[cfg(target_os = "ios")]
                TargetKind::Stdout | TargetKind::Stderr => fern::Output::call(move |record| {
                    let message = format!("{}", record.args());
                    unsafe {
                        ios::tauri_log(
                            match record.level() {
                                log::Level::Trace | log::Level::Debug => 1,
                                log::Level::Info => 2,
                                log::Level::Warn | log::Level::Error => 3,
                            },
                            // The string is allocated in rust, so we must
                            // autorelease it rust to give it to the Swift
                            // runtime.
                            objc2::rc::Retained::autorelease_ptr(
                                objc2_foundation::NSString::from_str(message.as_str()),
                            ) as _,
                        );
                    }
                }),
                #[cfg(desktop)]
                TargetKind::Stdout => std::io::stdout().into(),
                #[cfg(desktop)]
                TargetKind::Stderr => std::io::stderr().into(),
                TargetKind::Folder { path, file_name } => {
                    if !path.exists() {
                        fs::create_dir_all(&path)?;
                    }

                    let rotator = RotatingFile::new(
                        &path,
                        file_name.unwrap_or(app_name.clone()),
                        max_file_size,
                        rotation_strategy.clone(),
                        timezone_strategy.clone(),
                        file_open_strategy.clone(),
                    )?;
                    fern::Output::writer(Box::new(rotator), "\n")
                }
                TargetKind::LogDir { file_name } => {
                    let path = app_handle.path().app_log_dir()?;
                    if !path.exists() {
                        fs::create_dir_all(&path)?;
                    }

                    let rotator = RotatingFile::new(
                        &path,
                        file_name.unwrap_or(app_name.clone()),
                        max_file_size,
                        rotation_strategy.clone(),
                        timezone_strategy.clone(),
                        file_open_strategy.clone(),
                    )?;
                    fern::Output::writer(Box::new(rotator), "\n")
                }
                TargetKind::Webview => {
                    let app_handle = app_handle.clone();

                    fern::Output::call(move |record| {
                        let payload = RecordPayload {
                            message: record.args().to_string(),
                            level: record.level().into(),
                        };
                        let app_handle = app_handle.clone();
                        tauri::async_runtime::spawn(async move {
                            let _ = app_handle.emit("log://log", payload);
                        });
                    })
                }
                TargetKind::Dispatch(dispatch) => dispatch.into(),
            };
            target_dispatch = target_dispatch.chain(logger);

            dispatch = dispatch.chain(target_dispatch);
        }

        Ok(dispatch.into_log())
    }

    fn plugin_builder<R: Runtime>() -> plugin::Builder<R> {
        plugin::Builder::new("log").invoke_handler(tauri::generate_handler![commands::log])
    }

    #[allow(clippy::type_complexity)]
    pub fn split<R: Runtime>(
        self,
        app_handle: &AppHandle<R>,
    ) -> Result<(TauriPlugin<R>, log::LevelFilter, Box<dyn log::Log>), Error> {
        if self.is_skip_logger {
            return Err(Error::LoggerNotInitialized);
        }
        let plugin = Self::plugin_builder();
        let (max_level, log) = Self::acquire_logger(
            app_handle,
            self.dispatch,
            self.rotation_strategy,
            self.timezone_strategy,
            self.file_open_strategy,
            self.max_file_size as u64,
            self.targets,
        )?;

        Ok((plugin.build(), max_level, log))
    }

    pub fn build<R: Runtime>(self) -> TauriPlugin<R> {
        Self::plugin_builder()
            .setup(move |app_handle, _api| {
                if !self.is_skip_logger {
                    let (max_level, log) = Self::acquire_logger(
                        app_handle,
                        self.dispatch,
                        self.rotation_strategy,
                        self.timezone_strategy,
                        self.file_open_strategy,
                        self.max_file_size as u64,
                        self.targets,
                    )?;
                    attach_logger(max_level, log)?;
                }
                Ok(())
            })
            .build()
    }
}

/// Attaches the given logger
pub fn attach_logger(
    max_level: log::LevelFilter,
    log: Box<dyn log::Log>,
) -> Result<(), log::SetLoggerError> {
    log::set_boxed_logger(log)?;
    log::set_max_level(max_level);
    Ok(())
}