mxl_base/
logging.rs

1use crate::localization::helper::fl;
2use anyhow::Result;
3use log::*;
4use std::{
5    collections::HashMap,
6    path::{Path, PathBuf},
7    sync::{LazyLock, OnceLock},
8};
9
10const DEFAULT_LEVEL: log::LevelFilter = log::LevelFilter::Trace;
11const LOG_FILE_EXTENSION: &str = "log";
12
13#[cfg(debug_assertions)] // Set debug level for console in debug builds
14const CONSOLE_LEVEL: log::LevelFilter = log::LevelFilter::Trace;
15
16#[cfg(not(debug_assertions))] // Set debug level for console in release builds
17const CONSOLE_LEVEL: log::LevelFilter = log::LevelFilter::Warn;
18
19static LOG_RECEIVER_LOG_LEVEL: LazyLock<std::sync::RwLock<log::LevelFilter>> =
20    LazyLock::new(|| std::sync::RwLock::new(DEFAULT_LEVEL));
21
22pub fn set_log_level(level: log::LevelFilter) {
23    *LOG_RECEIVER_LOG_LEVEL.write().unwrap() = level;
24}
25
26pub fn get_log_level() -> log::LevelFilter {
27    *LOG_RECEIVER_LOG_LEVEL.read().unwrap()
28}
29
30static CURRENT_LOG_FILE_HOLDER: OnceLock<PathBuf> = OnceLock::new();
31pub fn current_log_file() -> &'static PathBuf {
32    CURRENT_LOG_FILE_HOLDER.get().expect("init() must be called first")
33}
34
35#[derive(Default)]
36pub struct Builder {
37    level_for: HashMap<&'static str, log::LevelFilter>,
38    console_level_for: HashMap<&'static str, log::LevelFilter>,
39    without_stderr: bool,
40}
41
42impl Builder {
43    pub fn new() -> Self {
44        Self::default()
45    }
46
47    pub fn level_for(mut self, module: &'static str, level: log::LevelFilter) -> Self {
48        self.level_for.insert(module, level);
49        self
50    }
51
52    pub fn console_level_for(mut self, module: &'static str, level: log::LevelFilter) -> Self {
53        self.console_level_for.insert(module, level);
54        self
55    }
56
57    pub fn without_stderr(mut self) -> Self {
58        self.without_stderr = true;
59        self
60    }
61
62    fn build_with_panic_on_failure(&self, log_dir: &Path) {
63        // NOTE!!!
64        // Every error MUST be a panic here else the user will not be able to see the error!
65        let mut logger = fern::Dispatch::new().level(DEFAULT_LEVEL);
66        for (module, level) in &self.level_for {
67            logger = logger.level_for(*module, *level);
68        }
69        logger = logger
70            .filter(|metadata| metadata.level() <= *LOG_RECEIVER_LOG_LEVEL.read().unwrap())
71            .format(|out, message, record| {
72                out.finish(format_args!("{} [{}] {}", record.level(), record.target(), message))
73            });
74        let log_file = CURRENT_LOG_FILE_HOLDER
75            .get_or_init(|| log_dir.join(format!("{}.{}", super::about::about().binary_name, LOG_FILE_EXTENSION)));
76
77        std::fs::create_dir_all(log_dir).unwrap_or_else(|error| {
78            panic!(
79                "Cannot create logging directory '{}': {:?}",
80                log_dir.to_string_lossy(),
81                error
82            )
83        });
84        logger = logger.chain(
85            fern::log_file(log_file)
86                .unwrap_or_else(|error| panic!("Cannot open log file '{}': {:?}", log_file.to_string_lossy(), error)),
87        );
88        if !self.without_stderr {
89            let mut console_logger = fern::Dispatch::new().level(CONSOLE_LEVEL).chain(std::io::stderr());
90            for (module, level) in &self.level_for {
91                console_logger = console_logger.level_for(*module, *level);
92            }
93            for (module, level) in &self.console_level_for {
94                console_logger = console_logger.level_for(*module, *level);
95            }
96            logger = logger.chain(console_logger);
97        }
98        logger.apply().expect("Cannot start logging");
99    }
100
101    pub fn build(self, log_dir: &Path) -> Result<()> {
102        self.build_with_panic_on_failure(log_dir);
103        let about = super::about::about();
104
105        let log_file = current_log_file();
106        if !self.without_stderr {
107            // Currently not use translation. The log file name is wrapped to: <2068>log-file-name<2069>
108            // Some terminals copy these possibly invisible special characters when selecting and copying,
109            // so that the log file cannot be opened.
110            if false {
111                println!("{}", fl!("log-written-to", file_name = log_file.to_string_lossy()));
112            } else {
113                println!("Log is written to '{}'", log_file.to_string_lossy());
114            }
115        }
116
117        info!("{} {}", about.app_name, about.version);
118        info!("Log is written to '{}'", log_file.to_string_lossy());
119
120        Ok(())
121    }
122}
mxl_base/logging.rs

mxl_base/
logging.rs
