casual_logger

This logger is intended to be easy to explain when teaching other example programs to friends.
Not for you, for self-study of beginner friends.
Of course you can use it.
Not for production, but better than not logging.

At first, Disclaim

At second, Overall view

Your code:

```rust use casual_logger::{Level, Log, Table, LOGGER};

fn main() { let removenum = if let Ok(mut logger) = LOGGER.lock() { // Do not call 'Log::xxxxx()' in this code block. // // Set file name. // // All: 'tic-tac-toe-2020-07-12.log.toml' // Prefix: 'tic-tac-toe' // StartDate: '-2020-07-12' automatically. // Suffix: '.log' - To be safe, include a word that // clearly states that you can delete the file. // Extention: '.toml' // // If you don't like the .toml extension, leave the // suffix empty and the .log extension. logger.setfile_name("tic-tac-toe", ".log", ".toml");

    logger.retention_days = 2;
    // The higher this level, the more will be omitted.
    //
    // |<-- Low Level --------------------- High level -->|
    // |<-- High priority --------------- Low priority -->|
    // |Fatal< Error < Warn < Notice < Info < Debug <Trace|
    logger.level = Level::Trace;
    // Remove old log files. This is determined by the
    // StartDate in the filename.
    logger.remove_old_logs()
} else {
    0
};
Log::noticeln(&format!("Remove {} files.", remove_num));

// Multi-line string.
// The suffix "ln" adds a newline at the end.
Log::infoln(
    "Hello, world!!

こんにちわ、世界！！", );

// After explicitly checking the level.
if Log::enabled(Level::Info) {
    let x = 100; // Time-consuming preparation, here.
    Log::infoln(&format!("x is {}.", x));
}

// The level is implicitly confirmed.
Log::trace("A,");
Log::traceln("B,");
Log::debug("C,");
Log::debugln("D,");
Log::info("E,");
Log::infoln("F,");
Log::notice("G,");
Log::noticeln("H,");
Log::warn("I,");
Log::warnln("J,");
Log::error("K,");
Log::errorln("L,");
Log::fatal("M,");
Log::fatalln("N!");

// Suffix '_t'. TOML say a table. So-called map.
Log::infoln_t(
    "The sky is from top to bottom!!

上から下まで空です！！", Table::default() .str( // Do not include spaces in your key. "ABird", "fly in the sky.", ) // Not enclose this value in quotation marks. .literal("NumberOfSwimmingFish", "2") .str( "ThreeMonkeys", "climb a tall tree.", ), );

// Wait for logging to complete. Time out 30 seconds.
Log::wait_for_logging_to_complete(
    30, |elapsed_secs, rest_threads|
{
    println!(
        "{} second(s). Wait for {} thread(s).",
        elapsed_secs, rest_threads
    );
});

} ```

Output ./default-2020-07-13.log.toml auto generated:

```toml ["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=3"] Info = "x is 100.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=24"] Error = "(2)Error on (7)Trace.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=33"] Notice = "(4)Notice on (5)Info.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=28"] Notice = "(4)Notice on (6)debug.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=22"] Notice = "(4)Notice on (7)Trace.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=27"] Info = "(5)Info on (6)debug.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=23"] Warn = "(3)Warn on (7)Trace.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=29"] Warn = "(3)Warn on (6)debug.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=30"] Error = "(2)Error on (6)debug.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=31"] Fatal = "(1)Fatal on (6)debug.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=32"] Info = "(5)Info on (5)Info.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=25"] Fatal = "(1)Fatal on (7)Trace.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=34"] Warn = "(3)Warn on (5)Info.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=11"] Notice = "H,\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=1"] Notice = "Remove 0 files.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=35"] Error = "(2)Error on (5)Info.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=36"] Fatal = "(1)Fatal on (5)Info.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=37"] Notice = "(4)Notice on (4)Notice.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=5"] Trace = "B,\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=38"] Warn = "(3)Warn on (4)Notice.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=39"] Error = "(2)Error on (4)Notice.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=40"] Fatal = "(1)Fatal on (4)Notice.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=41"] Warn = "(3)Warn on (3)Warn.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=42"] Error = "(2)Error on (3)Warn.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=43"] Fatal = "(1)Fatal on (3)Warn.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=45"] Fatal = "(1)Fatal on (2)Error.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=44"] Error = "(2)Error on (2)Error.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=46"] Fatal = "(1)Fatal on (1)Fatal.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=2"] Info = """ Hello, world!! こんにちわ、世界！！\r\n """

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=12"] Warn = "I,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=15"] Error = "L,\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=10"] Notice = "G,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=7"] Debug = "D,\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=8"] Info = "E,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=6"] Debug = "C,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=14"] Error = "K,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=13"] Warn = "J,\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=17"] Fatal = "N!\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=9"] Info = "F,\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=19"] Trace = "(7)Trace on (7)Trace.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=4"] Trace = "A,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=20"] Debug = "(6)Debug on (7)Trace.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=16"] Fatal = "M,"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=26"] Debug = "(6)Debug on (6)debug.\r\n"

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=18"] Info = """ The sky is from top to bottom!! 上から下まで空です！！\r\n """ ABird = "fly in the sky." NumberOfSwimmingFish = 2 ThreeMonkeys = """ climb a tall tree. """

["Now=2020-07-13 00:04:56&Pid=9012&Thr=ThreadId(1)&Seq=21"] Info = "(5)Info on (7)Trace.\r\n"

```

At third, Description

Code:

rust use casual_logger::{Level, Log, Table, LOGGER};

At the timing of the first writing, a file with a
time stamp in its name is automatically generated.
For example: ./tic-tac-toe-2020-07-12.log.toml

Description:

| Part | Name | Description | Default | | ------------- | --------- | ----------------- | --------- | | ./ | file path | Working directory | | | | | only. | | | tic-tac-toe | Prefix | Editable. | default | | -2020-07-12 | StartDate | Auto generated. | | | .log | Suffix | Editable. | .log | | .toml | Extension | Editable. | .toml |

It is difficult to explain the file path for beginners.
Therefore, it does not move.

Excite yourself with a prefix.

StartDate is basically today.
If the rotation fails, it is the start date.

Suffix to be safe, include a word that
clearly states that you can delete the file.

If you don't like the .toml extension, leave
the suffix empty and the .log extension.

Set up, Code:

```rust fn main() { if let Ok(mut logger) = LOGGER.lock() { logger.setfilename("tic-tac-toe", ".log", ".toml"); logger.retention_days = 2; logger.level = Level::Trace; }

// ...

} ```

Log rotation, Code:

rust let remove_num = if let Ok(mut logger) = LOGGER.lock() { logger.remove_old_logs() } else { 0 }; Log::noticeln(&format!("Remove {} files.", remove_num));

Logger Properties

| Name | Description | Default | | ---------------- | -------------------------- | ------- | | retention_days | After this number of days, | 7 | | | the file will be deleted. | | | level | Used to switch between | Trace | | | write and non-write. | |

Example of retention_days:

Example of level:

| Level | Examle of use. | | -------- | -------------------------------------------------- | | Fatal | If the program cannot continue. | | Error | I didn't get the expected result, | | | so I'll continue with the other method. | | Warn | It will be abnormal soon, | | | but there is no problem and you can ignore it. | | | For example: | | | (1) He reported that it took longer to access | | | than expected. | | | (2) Report that capacity is approaching the limit. | | Notice | It must be enabled in the server production | | | environment. | | | Record of passing important points correctly. | | | We are monitoring that it is working properly. | | Info | Report highlights. | | | Everything that needs to be reported regularly in | | | the production environment. | | Debug | It should be in a place with many accidents. | | | This level is disabled in production environments. | | | Leave it in the source and enable it for | | | troubleshooting. | | | Often, this is the production level of a desktop | | | operating environment. | | Trace | Not included in the distribution. | | | Remove this level from the source after using it | | | for debugging. | | | If you want to find a bug in the program, | | | write a lot. |

Code:

```rust // Multi-line string. // The suffix "ln" adds a newline at the end. Log::infoln( "Hello, world!! こんにちわ、世界！！", );

// After explicitly checking the level.
if Log::enabled(Level::Info) {
    let x = 100; // Time-consuming preparation, here.
    Log::infoln(&format!("x is {}.", x));
}

// The level is implicitly confirmed.
Log::trace("A,");
Log::traceln("B,");
Log::debug("C,");
Log::debugln("D,");
Log::info("E,");
Log::infoln("F,");
Log::notice("G,");
Log::noticeln("H,");
Log::warn("I,");
Log::warnln("J,");
Log::error("K,");
Log::errorln("L,");
Log::fatal("M,");
Log::fatalln("N!");

```

Usage of Table

| Static method | Description | | ------------- | ------------------ | | ::default() | Create a instance. |

| Instance method | Description | | ---------------------- | ------------------------------ | | .str(key, value) | Insert a string. | | | Multi-line string are | | | output with multiple lines. | | .literal(key, value) | Not enclose this value in | | | quotation marks. | | | You can break the toml format. | | | Do not validate. |

Do not include spaces in the key. TOML collapses.

It is difficult to explain to beginners how to use TOML.
If you make a TOML that cannot be parsed literally,
please correct it.

Code:

rust // Suffix '_t'. TOML say a table. So-called map. Log::infoln_t( "The sky is from top to bottom!! 上から下まで空です！！", Table::default() .str( // Do not include spaces in your key. "ABird", "fly in the sky.", ) // Not enclose this value in quotation marks. .literal("NumberOfSwimmingFish", "2") .str( "ThreeMonkeys", "climb a tall tree.", ), );

Output:

```toml ["Now=2020-07-12 18:35:23&Pid=20872&Thr=ThreadId(1)&Seq=18"] Info = """ The sky is from top to bottom!! 上から下まで空です！！\r\n """ ABird = "fly in the sky." NumberOfSwimmingFish = 2 ThreeMonkeys = """ climb a tall tree. """

```

Don't forget wait for logging to complete at end of program

Code:

rust // Wait for logging to complete. Time out 30 seconds. Log::wait_for_logging_to_complete( 30, |elapsed_secs, rest_threads| { println!( "{} second(s). Wait for {} thread(s).", elapsed_secs, rest_threads ); });

If you do not wait,
the program will exit before writing all the logs.

TODO

Tested environment

Appendix

Customize method

Code: main.rs

```rust use casual_logger::Log;

pub trait LogExt { fn println(s: &str); } impl LogExt for Log { /// Info level logging and add print to stdout. fn println(s: &str) { println!("{}", s); Log::infoln(s); } } ```

Usage: other.rs

```rust use crate::LogExt;

pub fn test() { Log::println("Hello, world!!"); } ```