├── .gitignore ├── CONTRIBUTING.md ├── Cargo.toml ├── LICENSE-APACHE ├── LICENSE-MIT ├── README.md ├── examples ├── custom-format.rs ├── custom-theme.rs ├── default.rs ├── inline-gradient.rs ├── json.rs ├── multi-line-gradient.rs ├── multi-threaded.rs └── util.rs ├── images ├── inline-gradient-color.png ├── multi-line-gradient.png ├── simple-theme.svg ├── solid-color.png ├── spectral-theme.svg ├── swing.gif └── swing.svg └── src ├── color.rs ├── config.rs ├── lib.rs ├── paint.rs ├── sculpt.rs ├── theme.rs └── write.rs /.gitignore: -------------------------------------------------------------------------------- 1 | # Generated by Cargo 2 | # will have compiled files and executables 3 | /target/ 4 | 5 | # Remove Cargo.lock from gitignore if creating an executable, leave it for libraries 6 | # More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html 7 | Cargo.lock 8 | 9 | # These are backup files generated by rustfmt 10 | **/*.rs.bk 11 | 12 | # IDEs 13 | .idea/ 14 | *.swp 15 | 16 | 17 | # Added by cargo 18 | 19 | /target 20 | 21 | 22 | # Added by cargo 23 | # 24 | # already existing elements were commented out 25 | 26 | #/target 27 | #Cargo.lock 28 | -------------------------------------------------------------------------------- /CONTRIBUTING.md: -------------------------------------------------------------------------------- 1 | # Contributing 2 | 3 | Thank you for making/considering a contribution to this project! These guidelines are not rules, but are designed to help us keep this project easily maintainable and consistent. 4 | 5 | ## Commit messages 6 | 7 | Ideal commit messages give a high level description of your change, and are written in [the imperative mood](https://en.wikipedia.org/wiki/Imperative_mood). For example: 8 | 9 | ```shell 10 | # this is in the imperative mood 11 | $ git commit -m 'Add a cool new feature' 12 | 13 | # this is not 14 | $ git commit -m 'Added a cool new feature' 15 | 16 | # this is also not 17 | $ git commit -m 'Cool new feature' 18 | ``` 19 | 20 | Commit messages written this way make it easy to look at the `git log` and quickly grasp major actions/changes that take us from one commit to another. 21 | 22 | ## Styling and testing 23 | 24 | Before making a pull request, please format your changes and make sure all tests still pass: 25 | 26 | ```shell 27 | $ cargo fmt 28 | $ cargo test 29 | ``` -------------------------------------------------------------------------------- /Cargo.toml: -------------------------------------------------------------------------------- 1 | [package] 2 | name = "swing" 3 | version = "0.1.0" 4 | authors = ["Diffuse <48339639+diffuse@users.noreply.github.com>"] 5 | edition = "2018" 6 | readme = "README.md" 7 | repository = "https://github.com/diffuse/swing" 8 | license = "MIT/Apache-2.0" 9 | description = "Log like it's 1978 with this logging implementation for the log crate" 10 | keywords = ["log", "logging", "swing", "color"] 11 | categories = ["development-tools::debugging"] 12 | 13 | [dependencies] 14 | log = { version = "0.4", features = ["std", "serde"] } 15 | serde_json = { version = "1.0", features = ["preserve_order"]} 16 | time = { version = "0.3.11", features = ["formatting"] } 17 | colored = "2" 18 | unicode-segmentation = "1.9.0" 19 | 20 | [dev-dependencies] 21 | lipsum = "0.8" 22 | num = "0.4" 23 | rand = "0.8" 24 | -------------------------------------------------------------------------------- /LICENSE-APACHE: -------------------------------------------------------------------------------- 1 | 2 | Apache License 3 | Version 2.0, January 2004 4 | https://www.apache.org/licenses/ 5 | 6 | TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 7 | 8 | 1. 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IN NO EVENT SHALL THE 18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 21 | SOFTWARE. 22 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | swing logo 2 | 3 | # swing 4 | 5 | Log like it's 1978 with this logging implementation for the [log](https://crates.io/crates/log) crate. Color themes, pluggable formatting, we've got it all! 6 | 7 | ![multi-line-gradient](https://i.imgur.com/2cGHo5L.gif) 8 | 9 | # Installation 10 | 11 | Add the following to `Cargo.toml`: 12 | 13 | ```toml 14 | [dependencies] 15 | swing = "0.1" 16 | log = "0.4" 17 | ``` 18 | 19 | # Quick start 20 | 21 | Create and initialize a `Logger`, then use the [log](https://crates.io/crates/log) crate macros to log messages: 22 | 23 | ```rust 24 | use swing::Logger; 25 | 26 | fn main() { 27 | // setup logger 28 | Logger::new().init().unwrap(); 29 | 30 | // log away! 31 | log::trace!("foo"); 32 | log::debug!("bar"); 33 | log::info!("baz"); 34 | log::warn!("spam"); 35 | log::error!("eggs"); 36 | } 37 | ``` 38 | 39 | Note that the default `Logger` created with `::new()` has a log level filter of `info`, so in this example, only `"baz"` `"spam"` and `"eggs"` will be printed to the console. 40 | 41 | # Logger config options 42 | 43 | For more control, `Logger`s can be created with a `Config` struct via `Logger::with_config`: 44 | 45 | ```rust 46 | use swing::{Config, Logger}; 47 | use log::LevelFilter; 48 | 49 | fn main() { 50 | let config = Config { 51 | level: LevelFilter::Trace, 52 | ..Default::default() 53 | }; 54 | 55 | Logger::with_config(config).init().unwrap(); 56 | } 57 | ``` 58 | 59 | The default configuration uses the following settings: 60 | 61 | ```rust 62 | use swing::{Config, ColorFormat, RecordFormat, theme}; 63 | use log::LevelFilter; 64 | 65 | Config { 66 | level: LevelFilter::Info, 67 | record_format: RecordFormat::Simple, 68 | color_format: Some(ColorFormat::Solid), 69 | theme: Box::new(theme::Spectral {}), 70 | use_stderr: true, 71 | }; 72 | ``` 73 | 74 | Each setting is explained in its own subsection: 75 | 76 | - [level](#level) 77 | - [record_format](#record_format) 78 | - [color_format](#color_format) 79 | - [theme](#theme) 80 | - [use_stderr](#use_stderr) 81 | 82 | ## level 83 | 84 | The `level` setting controls which log records are processed and which are ignored. The `LevelFilter` enum used in `Config` is taken directly 85 | from [the log crate](https://docs.rs/log/latest/log/enum.LevelFilter.html). It defines the following variants: 86 | 87 | - `Off` 88 | - `Trace` 89 | - `Debug` 90 | - `Info` 91 | - `Warn` 92 | - `Error` 93 | 94 | Only records logged at or above the chosen severity will be output to `stdout`/`stderr`. For example: 95 | 96 | ```rust 97 | use swing::Config; 98 | use log::LevelFilter; 99 | 100 | // --snip-- 101 | 102 | let config = Config { 103 | level: LevelFilter::Info, 104 | ..Default::default() 105 | }; 106 | 107 | // --snip-- 108 | 109 | // trace and debug logs will be ignored, only info, warn, and error messages will print to the screen 110 | log::trace!("foo"); 111 | log::debug!("bar"); 112 | log::info!("baz"); 113 | log::warn!("spam"); 114 | log::error!("eggs"); 115 | ``` 116 | 117 | ## record_format 118 | 119 | The `record_format` setting controls how log records are (structurally) formatted when they are displayed. Each call to the [log](https://docs.rs/log/latest/log/) 120 | crate macros (`trace!`, `info!`, etc...) generates a log [record](https://docs.rs/log/latest/log/struct.Record.html). These records are then formatted by this crate using one 121 | of the variants in the `RecordFormat` enum: 122 | 123 | - `Json` 124 | - `Simple` 125 | - `Custom` 126 | 127 | Record formats are imported and used by: 128 | 129 | ```rust 130 | use swing::{Config, Logger, RecordFormat}; 131 | use log::LevelFilter; 132 | 133 | fn main() { 134 | let config = Config { 135 | level: LevelFilter::Trace, 136 | record_format: RecordFormat::Simple, 137 | ..Default::default() 138 | }; 139 | Logger::with_config(config).init().unwrap(); 140 | } 141 | ``` 142 | 143 | ### Simple format 144 | 145 | This is the default record format and will generate log lines that look like this: 146 | 147 | ```text 148 | 2022-07-31T20:25:31.108560826Z [main] TRACE - foo 149 | 2022-07-31T20:25:31.108623041Z [main] DEBUG - bar 150 | 2022-07-31T20:25:31.108645580Z [main] INFO - baz 151 | 2022-07-31T20:25:31.108667634Z [main] WARN - spam 152 | 2022-07-31T20:25:31.108736790Z [main] ERROR - eggs 153 | ``` 154 | 155 | Note that times are always in ISO 8601 format, UTC time. 156 | 157 | ### Json format 158 | 159 | This record format will generate log lines as JSON: 160 | 161 | ```json 162 | {"time":"2022-07-31T20:28:11.863634602Z","level":"TRACE","target":"main","message":"foo"} 163 | {"time":"2022-07-31T20:28:11.864114090Z","level":"DEBUG","target":"main","message":"bar"} 164 | {"time":"2022-07-31T20:28:11.864201937Z","level":"INFO","target":"main","message":"baz"} 165 | {"time":"2022-07-31T20:28:11.864269093Z","level":"WARN","target":"main","message":"spam"} 166 | {"time":"2022-07-31T20:28:11.864372619Z","level":"ERROR","target":"main","message":"eggs"} 167 | ``` 168 | 169 | Note that times are always in ISO 8601 format, UTC time. 170 | 171 | ### Custom format 172 | 173 | If you don't like any of the above formats, you can inject your own custom record formatting by using the `Custom` format: 174 | 175 | ```rust 176 | use swing::{Config, Logger, RecordFormat}; 177 | use log::{LevelFilter, Record}; 178 | 179 | fn main() { 180 | let fmt_rec = Box::new(|r: &Record| -> String { 181 | format!("{} - {}", r.level(), r.args()) 182 | }); 183 | 184 | let config = Config { 185 | level: LevelFilter::Trace, 186 | record_format: RecordFormat::Custom(fmt_rec), 187 | ..Default::default() 188 | }; 189 | Logger::with_config(config).init().unwrap(); 190 | 191 | // log away! 192 | log::trace!("foo"); 193 | log::debug!("bar"); 194 | log::info!("baz"); 195 | log::warn!("spam"); 196 | log::error!("eggs"); 197 | } 198 | ``` 199 | 200 | The above example format will generate log lines that look like this: 201 | 202 | ```text 203 | TRACE - foo 204 | DEBUG - bar 205 | INFO - baz 206 | WARN - spam 207 | ERROR - eggs 208 | ``` 209 | 210 | See [the log crate "Record" struct](https://docs.rs/log/latest/log/struct.Record.html) for available record fields/methods to use within the custom format closure. 211 | 212 | For reference, the `Simple` record format can be reproduced with the following `Custom` record format: 213 | 214 | ```rust 215 | use time::format_description::well_known::Iso8601; 216 | use time::OffsetDateTime; 217 | use log::Record; 218 | 219 | // --snip-- 220 | 221 | let fmt_rec = Box::new(|r: &Record| -> String { 222 | let now = OffsetDateTime::now_utc() 223 | .format(&Iso8601::DEFAULT) 224 | .expect("Failed to format time as ISO 8601"); 225 | 226 | format!("{} [{}] {} - {}", now, r.target(), r.level(), r.args()) 227 | }); 228 | ``` 229 | 230 | ## color_format 231 | 232 | The `color_format` setting controls how log records are colored (specifically how a theme is applied) when they are displayed. Log records are formatted by this crate using one of the variants in the `ColorFormat` enum, or `None`: 233 | 234 | - `Solid` 235 | - `InlineGradient()` 236 | - `MultiLineGradient()` 237 | 238 | Color formats are imported and used by: 239 | 240 | ```rust 241 | use swing::{Config, Logger, ColorFormat}; 242 | use log::LevelFilter; 243 | 244 | fn main() { 245 | let config = Config { 246 | level: LevelFilter::Trace, 247 | color_format: Some(ColorFormat::Solid), 248 | ..Default::default() 249 | }; 250 | Logger::with_config(config).init().unwrap(); 251 | } 252 | ``` 253 | 254 | ### None format 255 | 256 | If `None` is provided as the `color_format`, log records will not be colored (warnings and errors will still be made bold). 257 | 258 | ### Solid format 259 | 260 | This will generate log lines that each have a solid color, determined by log level. The below screenshot uses the `Spectral` theme and the following color format: 261 | ```rust 262 | use swing::ColorFormat; 263 | 264 | // --snip-- 265 | 266 | let color_format = Some(ColorFormat::Solid); 267 | ``` 268 | ![solid color format](https://i.imgur.com/AiSOt2W.png) 269 | 270 | ### Inline gradient format 271 | 272 | This will generate log lines that are colored with a repeating linear gradient from left to right, determined by log level. The below screenshot uses the `Spectral` theme and the following color format: 273 | ```rust 274 | use swing::ColorFormat; 275 | 276 | // --snip-- 277 | 278 | let color_format = Some(ColorFormat::InlineGradient(60)); 279 | ``` 280 | ![inline gradient color format](https://i.imgur.com/RkGZWEh.png) 281 | 282 | This color format takes a `usize` argument which represents the number of steps required to go from the start color to the end color for each level's color gradient. Gradients will be traversed in alternating ascending and descending order. In the above example, it will take `60` characters to go from the starting color for each line to the ending color, then `60` more characters to return to the starting color again. 283 | 284 | Note that this color format will incur a nontrivial performance hit with heavy logging. If you have a lot of logs and are trying to break the next land speed record for fastest program, you probably shouldn't use this color format. 285 | 286 | ### Multi-line gradient format 287 | 288 | This will generate log lines that each have a solid color, determined by level. Lines within each level will change color step by step, moving through a linear gradient of colors determined by the relevant log level. The below screenshot uses the `Spectral` theme and the following color format: 289 | ```rust 290 | use swing::ColorFormat; 291 | 292 | // --snip-- 293 | 294 | let color_format = Some(ColorFormat::MultiLineGradient(30)); 295 | ``` 296 | ![multi-line gradient](https://i.imgur.com/x4Z0tN3.png) 297 | 298 | This color format takes a `usize` argument which represents the number of steps required to go from the start color to the end color for each level's color gradient. Gradients will be traversed in alternating ascending and descending order. In the above example, it will take `30` lines to go from the starting color for each level to the ending color, then `30` more lines to return to the starting color again. 299 | 300 | ## theme 301 | 302 | The `theme` setting determines the color palette to use when applying color formats. It is set by providing an instance of something that implements the `Theme` trait: 303 | ```rust 304 | use swing::theme::Spectral; 305 | 306 | // --snip-- 307 | 308 | let theme = Box::new(Spectral {}); 309 | ``` 310 | 311 | This crate provides a few premade themes, but you can also implement your own, or use themes made by others. 312 | 313 | ### Spectral 314 | 315 | The `Spectral` theme provides a palette that moves through the color spectrum in 5 segments: 316 | 317 | ![spectral theme](https://i.imgur.com/DIdDbI7.png) 318 | 319 | ### Simple 320 | 321 | The `Simple` theme provides a relatively flat palette that uses dark/light versions of 5 main colors: 322 | 323 | ![simple theme](https://i.imgur.com/Rrku1BP.png) 324 | 325 | ### Creating your own custom theme 326 | 327 | Anything that implements the `Theme` trait can be used as a theme. To make your own theme, you just have to implement this trait for a struct, then set `Config`'s `theme` member to a boxed instance of that struct. See `examples/custom-theme.rs` for an example of a custom theme implementation. 328 | 329 | ## use_stderr 330 | 331 | The `use_stderr` setting determines if log records are split between `stdout` and `stderr` or not. When this field is false, all log records will be written to `stdout`. When this field is true, records at levels `trace`, `debug`, and `info` are written to `stdout`, while those at `warn` and `error` levels are written to `stderr`. 332 | 333 | # Examples 334 | 335 | See the `examples` directory for a variety of usage examples. You can run any of these examples with: 336 | ```shell 337 | $ cargo run --example 338 | ``` 339 | 340 | # Stream redirection tips in Linux 341 | 342 | When logging with `use_stderr` set to true, you must redirect both streams to capture all output. 343 | 344 | To redirect all log records to file: 345 | 346 | ```shell 347 | $ ./example &> foo.log 348 | ``` 349 | 350 | To redirect all logs to file, while watching output: 351 | 352 | ```shell 353 | # write all log data to foo.log and stdout simultaneously 354 | $ ./example 2>&1 | tee foo.log 355 | ``` 356 | 357 | You can add `jq` for pretty printing when using `RecordFormat::Json`: 358 | 359 | ```shell 360 | $ ./example 2>&1 | tee foo.log | jq 361 | ``` 362 | 363 | # Contributing 364 | 365 | Contributions are welcome and greatly appreciated. See [CONTRIBUTING](CONTRIBUTING.md) for some general guidelines. 366 | 367 | # License 368 | 369 | Licensed under either of [Apache License, Version 2.0](https://github.com/diffuse/swing/blob/main/LICENSE-APACHE) or [MIT license](https://github.com/diffuse/swing/blob/main/LICENSE-MIT) at your option. 370 | 371 | Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in swing by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions. -------------------------------------------------------------------------------- /examples/custom-format.rs: -------------------------------------------------------------------------------- 1 | use log::{LevelFilter, Record}; 2 | use swing::{Config, Logger, RecordFormat}; 3 | 4 | fn main() { 5 | // create your own conversion from a 6 | // log::Record to a String and wrap it 7 | // in a Box to use with a Logger 8 | let fmt_rec = Box::new(|r: &Record| -> String { 9 | format!("[{}] {} - {}", r.target(), r.level(), r.args()) 10 | }); 11 | 12 | // setup logger 13 | let config = Config { 14 | level: LevelFilter::Trace, 15 | record_format: RecordFormat::Custom(fmt_rec), 16 | ..Default::default() 17 | }; 18 | Logger::with_config(config).init().unwrap(); 19 | 20 | // log away! 21 | log::trace!("foo"); 22 | log::debug!("bar"); 23 | log::info!("baz"); 24 | log::warn!("spam"); 25 | log::error!("eggs"); 26 | } 27 | -------------------------------------------------------------------------------- /examples/custom-theme.rs: -------------------------------------------------------------------------------- 1 | use log::{Level, LevelFilter}; 2 | use swing::{Color, ColorFormat, Config, Logger, Rgb, RgbRange, Theme}; 3 | 4 | /// Custom theme 5 | pub struct MyTheme {} 6 | 7 | impl Theme for MyTheme { 8 | /// This method returns the color that will be used for each 9 | /// level when the Solid color format is chosen 10 | /// 11 | /// This implementation simply uses the start color 12 | /// from each level's color range as its solid color, but you 13 | /// can perform another level match here and choose whichever 14 | /// specific colors you would like. 15 | fn solid(&self, level: Level) -> Rgb { 16 | self.range(level).start 17 | } 18 | 19 | /// This method returns a range of color that each log level will 20 | /// use. The provided color range defines the bounds for linear gradients, 21 | /// and can be used to calculate solid colors, if desired. 22 | fn range(&self, level: Level) -> RgbRange { 23 | match level { 24 | Level::Trace => RgbRange { 25 | start: Rgb { 26 | r: 245, 27 | g: 1, 28 | b: 167, 29 | }, 30 | end: Rgb { 31 | r: 245, 32 | g: 121, 33 | b: 167, 34 | }, 35 | }, 36 | Level::Debug => RgbRange { 37 | start: Color::Cyan.value(), 38 | end: Rgb { 39 | r: 162, 40 | g: 187, 41 | b: 214, 42 | }, 43 | }, 44 | Level::Info => RgbRange { 45 | start: Color::Green.value(), 46 | end: Rgb { 47 | r: 209, 48 | g: 235, 49 | b: 165, 50 | }, 51 | }, 52 | Level::Warn => RgbRange { 53 | start: Color::Yellow.value(), 54 | end: Rgb { 55 | r: 214, 56 | g: 202, 57 | b: 169, 58 | }, 59 | }, 60 | Level::Error => RgbRange { 61 | start: Color::Red.value(), 62 | end: Rgb { 63 | r: 245, 64 | g: 171, 65 | b: 171, 66 | }, 67 | }, 68 | } 69 | } 70 | } 71 | 72 | fn main() { 73 | // setup logger 74 | let config = Config { 75 | level: LevelFilter::Trace, 76 | theme: Box::new(MyTheme {}), 77 | color_format: Some(ColorFormat::InlineGradient(20)), 78 | ..Default::default() 79 | }; 80 | Logger::with_config(config).init().unwrap(); 81 | 82 | // log away! 83 | log::trace!("I looked forward to making a crate"); 84 | log::debug!("Where colors in logs annotate,"); 85 | log::info!("But encountered a yak"); 86 | log::warn!("And couldn't look back"); 87 | log::error!("'til the hair on that yak did abate"); 88 | } 89 | -------------------------------------------------------------------------------- /examples/default.rs: -------------------------------------------------------------------------------- 1 | use swing::Logger; 2 | 3 | fn main() { 4 | // setup logger 5 | Logger::new().init().unwrap(); 6 | 7 | // log away! 8 | log::trace!("foo"); 9 | log::debug!("bar"); 10 | log::info!("baz"); 11 | log::warn!("spam"); 12 | log::error!("eggs"); 13 | } 14 | -------------------------------------------------------------------------------- /examples/inline-gradient.rs: -------------------------------------------------------------------------------- 1 | use log::LevelFilter; 2 | use swing::{theme::Spectral, ColorFormat, Config, Logger, RecordFormat}; 3 | mod util; 4 | 5 | fn main() { 6 | // setup logger 7 | let config = Config { 8 | level: LevelFilter::Trace, 9 | record_format: RecordFormat::Simple, 10 | color_format: Some(ColorFormat::InlineGradient(200)), 11 | theme: Box::new(Spectral {}), 12 | ..Default::default() 13 | }; 14 | Logger::with_config(config).init().unwrap(); 15 | 16 | util::log_sample_messages(100); 17 | } 18 | -------------------------------------------------------------------------------- /examples/json.rs: -------------------------------------------------------------------------------- 1 | use log::LevelFilter; 2 | use swing::{Config, Logger, RecordFormat}; 3 | 4 | fn main() { 5 | // setup logger 6 | let config = Config { 7 | level: LevelFilter::Trace, 8 | record_format: RecordFormat::Json, 9 | ..Default::default() 10 | }; 11 | Logger::with_config(config).init().unwrap(); 12 | 13 | // log away! 14 | log::trace!("foo"); 15 | log::debug!("bar"); 16 | log::info!("baz"); 17 | log::warn!("spam"); 18 | log::error!("eggs"); 19 | } 20 | -------------------------------------------------------------------------------- /examples/multi-line-gradient.rs: -------------------------------------------------------------------------------- 1 | use log::LevelFilter; 2 | use swing::{theme::Spectral, ColorFormat, Config, Logger, RecordFormat}; 3 | mod util; 4 | 5 | fn main() { 6 | // setup logger 7 | let config = Config { 8 | level: LevelFilter::Trace, 9 | record_format: RecordFormat::Simple, 10 | color_format: Some(ColorFormat::MultiLineGradient(20)), 11 | theme: Box::new(Spectral {}), 12 | ..Default::default() 13 | }; 14 | Logger::with_config(config).init().unwrap(); 15 | 16 | util::log_sample_messages(1000); 17 | } 18 | -------------------------------------------------------------------------------- /examples/multi-threaded.rs: -------------------------------------------------------------------------------- 1 | use log::LevelFilter; 2 | use std::thread; 3 | use swing::{theme::Spectral, ColorFormat, Config, Logger}; 4 | mod util; 5 | 6 | fn main() { 7 | // setup logger 8 | let config = Config { 9 | level: LevelFilter::Trace, 10 | color_format: Some(ColorFormat::MultiLineGradient(20)), 11 | theme: Box::new(Spectral {}), 12 | ..Default::default() 13 | }; 14 | Logger::with_config(config).init().unwrap(); 15 | 16 | // log sample messages from 10 threads simultaneously 17 | let mut handles = vec![]; 18 | 19 | for _ in 0..10 { 20 | handles.push(thread::spawn(move || { 21 | util::log_sample_messages(1000); 22 | })); 23 | } 24 | 25 | for handle in handles { 26 | handle.join().unwrap(); 27 | } 28 | } 29 | -------------------------------------------------------------------------------- /examples/util.rs: -------------------------------------------------------------------------------- 1 | use lipsum::lipsum; 2 | use rand::Rng; 3 | 4 | /// log n sample messages, weighted towards the default _ match arm 5 | pub fn log_sample_messages(n: usize) { 6 | for _ in 0..n { 7 | let n = rand::thread_rng().gen_range(0..20); 8 | let msg = lipsum(n); 9 | 10 | match rand::thread_rng().gen_range(0..15) { 11 | 0 => log::trace!("{}", msg), 12 | 1 => log::debug!("{}", msg), 13 | 2 => log::info!("{}", msg), 14 | 3 => log::warn!("{}", msg), 15 | 4 => log::error!("{}", msg), 16 | _ => log::info!("{}", msg), 17 | }; 18 | } 19 | } 20 | 21 | #[allow(dead_code)] 22 | fn main() {} 23 | -------------------------------------------------------------------------------- /images/inline-gradient-color.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/diffuse/swing/3e735867dc5b57337943297f773969eb6a2eee43/images/inline-gradient-color.png -------------------------------------------------------------------------------- /images/multi-line-gradient.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/diffuse/swing/3e735867dc5b57337943297f773969eb6a2eee43/images/multi-line-gradient.png -------------------------------------------------------------------------------- /images/simple-theme.svg: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 23 | 25 | 28 | 32 | 36 | 37 | 40 | 44 | 48 | 49 | 52 | 56 | 60 | 61 | 64 | 68 | 72 | 73 | 81 | 87 | 88 | 98 | 101 | 105 | 109 | 110 | 119 | 129 | 139 | 149 | 159 | 160 | 178 | 180 | 181 | 183 | image/svg+xml 184 | 186 | 187 | 188 | 189 | 190 | 195 | 202 | 209 | 216 | 223 | 230 | trace 242 | debug 253 | info 264 | warn 275 | error 286 | 287 | 288 | -------------------------------------------------------------------------------- /images/solid-color.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/diffuse/swing/3e735867dc5b57337943297f773969eb6a2eee43/images/solid-color.png -------------------------------------------------------------------------------- /images/spectral-theme.svg: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 23 | 25 | 28 | 32 | 36 | 37 | 40 | 44 | 48 | 49 | 52 | 56 | 60 | 61 | 64 | 68 | 72 | 73 | 81 | 87 | 88 | 98 | 101 | 105 | 109 | 110 | 119 | 129 | 139 | 149 | 159 | 160 | 178 | 180 | 181 | 183 | image/svg+xml 184 | 186 | 187 | 188 | 189 | 190 | 195 | 202 | 209 | 216 | 223 | 230 | trace 242 | debug 253 | info 264 | warn 275 | error 286 | 287 | 288 | -------------------------------------------------------------------------------- /images/swing.gif: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/diffuse/swing/3e735867dc5b57337943297f773969eb6a2eee43/images/swing.gif -------------------------------------------------------------------------------- /images/swing.svg: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 21 | 23 | 26 | 30 | 34 | 35 | 45 | 54 | 55 | 74 | 76 | 77 | 79 | image/svg+xml 80 | 82 | 83 | 84 | 85 | 86 | 92 | 102 | 112 | 127 | 143 | 159 | 175 | 191 | 207 | 223 | 239 | 255 | 265 | 266 | 451 | 686 | 877 | 1068 | 1259 | 1265 | 1273 | 1276 | 1281 | 1282 | 1285 | 1290 | 1291 | 1296 | 1304 | 1305 | 1308 | 1313 | 1314 | 1317 | 1322 | 1323 | 1326 | 1331 | 1332 | 1335 | 1340 | 1341 | 1344 | 1349 | 1350 | 1355 | 1363 | 1364 | 1365 | 1386 | 1407 | 1428 | 1449 | 1450 | 1451 | -------------------------------------------------------------------------------- /src/color.rs: -------------------------------------------------------------------------------- 1 | //! Color related type definitions and constant values 2 | 3 | use colored::{self, Color::TrueColor}; 4 | 5 | /// RGB triplet 6 | #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, Default)] 7 | pub struct Rgb { 8 | /// red intensity 9 | pub r: u8, 10 | /// green intensity 11 | pub g: u8, 12 | /// blue intensity 13 | pub b: u8, 14 | } 15 | 16 | impl Into for Rgb { 17 | /// Convert Rgb -> Color for easier use with string coloring 18 | fn into(self) -> colored::Color { 19 | TrueColor { 20 | r: self.r, 21 | g: self.g, 22 | b: self.b, 23 | } 24 | } 25 | } 26 | 27 | /// RgbRange defines a linear color range from some start Rgb 28 | /// triplet -> some end Rgb triplet 29 | #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, Default)] 30 | pub struct RgbRange { 31 | /// start of color range 32 | pub start: Rgb, 33 | /// end of color range 34 | pub end: Rgb, 35 | } 36 | 37 | /// Constant predefined color values 38 | /// 39 | /// Use of these color values is not necessary when 40 | /// creating a theme, but they act as helpful aliases 41 | /// for raw Rgb triplets 42 | #[allow(dead_code)] 43 | pub enum Color { 44 | /// dark magenta 45 | DarkMagenta, 46 | /// magenta 47 | Magenta, 48 | /// dark pink 49 | DarkPink, 50 | /// pink 51 | Pink, 52 | /// dark cyan 53 | DarkCyan, 54 | /// cyan 55 | Cyan, 56 | /// dark blue 57 | DarkBlue, 58 | /// blue 59 | Blue, 60 | /// dark green 61 | DarkGreen, 62 | /// green 63 | Green, 64 | /// dark yellow 65 | DarkYellow, 66 | /// yellow 67 | Yellow, 68 | /// dark orange 69 | DarkOrange, 70 | /// orange 71 | Orange, 72 | /// dark red 73 | DarkRed, 74 | /// red 75 | Red, 76 | } 77 | 78 | impl Color { 79 | /// Return the Rgb triplet associated with a color variant 80 | pub fn value(&self) -> Rgb { 81 | match self { 82 | Color::DarkMagenta => Rgb { 83 | r: 139, 84 | g: 0, 85 | b: 139, 86 | }, 87 | Color::Magenta => Rgb { 88 | r: 255, 89 | g: 0, 90 | b: 255, 91 | }, 92 | Color::DarkPink => Rgb { 93 | r: 149, 94 | g: 119, 95 | b: 149, 96 | }, 97 | Color::Pink => Rgb { 98 | r: 227, 99 | g: 184, 100 | b: 227, 101 | }, 102 | Color::DarkCyan => Rgb { 103 | r: 10, 104 | g: 144, 105 | b: 144, 106 | }, 107 | Color::Cyan => Rgb { 108 | r: 20, 109 | g: 210, 110 | b: 210, 111 | }, 112 | Color::DarkBlue => Rgb { 113 | r: 70, 114 | g: 75, 115 | b: 185, 116 | }, 117 | Color::Blue => Rgb { 118 | r: 90, 119 | g: 100, 120 | b: 240, 121 | }, 122 | Color::DarkGreen => Rgb { 123 | r: 70, 124 | g: 140, 125 | b: 10, 126 | }, 127 | Color::Green => Rgb { 128 | r: 110, 129 | g: 220, 130 | b: 10, 131 | }, 132 | Color::DarkYellow => Rgb { 133 | r: 170, 134 | g: 128, 135 | b: 0, 136 | }, 137 | Color::Yellow => Rgb { 138 | r: 255, 139 | g: 185, 140 | b: 0, 141 | }, 142 | Color::DarkOrange => Rgb { 143 | r: 255, 144 | g: 128, 145 | b: 0, 146 | }, 147 | Color::Orange => Rgb { 148 | r: 250, 149 | g: 180, 150 | b: 110, 151 | }, 152 | Color::DarkRed => Rgb { 153 | r: 200, 154 | g: 0, 155 | b: 10, 156 | }, 157 | Color::Red => Rgb { 158 | r: 255, 159 | g: 60, 160 | b: 10, 161 | }, 162 | } 163 | } 164 | } 165 | 166 | #[cfg(test)] 167 | mod tests { 168 | use super::*; 169 | 170 | #[test] 171 | fn rgb_into_color_is_accurate() { 172 | let test_cases = vec![ 173 | (Rgb { r: 0, g: 0, b: 0 }, TrueColor { r: 0, g: 0, b: 0 }), 174 | ( 175 | Rgb { 176 | r: 127, 177 | g: 128, 178 | b: 129, 179 | }, 180 | TrueColor { 181 | r: 127, 182 | g: 128, 183 | b: 129, 184 | }, 185 | ), 186 | ( 187 | Rgb { 188 | r: 255, 189 | g: 255, 190 | b: 255, 191 | }, 192 | TrueColor { 193 | r: 255, 194 | g: 255, 195 | b: 255, 196 | }, 197 | ), 198 | ]; 199 | 200 | for (rgb, tc) in test_cases { 201 | let c: colored::Color = rgb.into(); 202 | assert_eq!(c, tc); 203 | } 204 | } 205 | } 206 | -------------------------------------------------------------------------------- /src/config.rs: -------------------------------------------------------------------------------- 1 | //! Configuration related definitions and implementation 2 | 3 | use crate::{paint::ColorFormat, sculpt::RecordFormat, theme::Spectral, theme::Theme}; 4 | use log::LevelFilter; 5 | 6 | /// Main configuration for a `Logger` 7 | pub struct Config { 8 | /// log level filter (logs below this severity will be ignored) 9 | pub level: LevelFilter, 10 | /// record formatting mode (determines how log records are structurally formatted) 11 | pub record_format: RecordFormat, 12 | /// color formatting mode (determines how log records are colored) 13 | pub color_format: Option, 14 | /// color theme (determines the color palette used to color log records) 15 | pub theme: Box, 16 | /// switch for enabling log splitting to `stderr` 17 | /// 18 | /// - `true`: log `trace` - `info` levels to `stdout` and `warn` - `error` levels to `stderr` 19 | /// 20 | /// - `false`: log all levels to `stdout` 21 | pub use_stderr: bool, 22 | } 23 | 24 | impl Default for Config { 25 | /// Return a `Config` with default values 26 | fn default() -> Config { 27 | Config { 28 | level: LevelFilter::Info, 29 | record_format: RecordFormat::Simple, 30 | color_format: Some(ColorFormat::Solid), 31 | theme: Box::new(Spectral {}), 32 | use_stderr: true, 33 | } 34 | } 35 | } 36 | -------------------------------------------------------------------------------- /src/lib.rs: -------------------------------------------------------------------------------- 1 | #![doc = include_str!("../README.md")] 2 | #![doc( 3 | html_logo_url = "https://i.imgur.com/xOjqfvy.gif", 4 | html_favicon_url = "https://i.imgur.com/Q7UUHoN.png", 5 | html_playground_url = "https://play.rust-lang.org/" 6 | )] 7 | #![deny(missing_docs)] 8 | 9 | use log::{LevelFilter, Log, Metadata, Record, SetLoggerError}; 10 | mod paint; 11 | use paint::LogPainter; 12 | mod sculpt; 13 | use sculpt::LogSculptor; 14 | mod write; 15 | use write::LogWriter; 16 | 17 | pub mod color; 18 | pub mod theme; 19 | pub use color::{Color, Rgb, RgbRange}; 20 | pub use paint::ColorFormat; 21 | pub use sculpt::RecordFormat; 22 | pub use theme::Theme; 23 | pub mod config; 24 | pub use config::Config; 25 | 26 | /// Implements log::Log 27 | pub struct Logger { 28 | /// Level-based filter for logs 29 | level_filter: LevelFilter, 30 | /// painter for logs 31 | log_painter: LogPainter, 32 | /// sculptor for logs 33 | log_sculptor: LogSculptor, 34 | /// writer for logs 35 | log_writer: LogWriter, 36 | } 37 | 38 | impl Logger { 39 | /// Create a new Logger with a default configuration 40 | pub fn new() -> Logger { 41 | Logger::with_config(Config::default()) 42 | } 43 | 44 | /// Create a new Logger with a custom configuration 45 | /// 46 | /// # Arguments 47 | /// 48 | /// * `config` - configuration for this logger 49 | pub fn with_config(config: Config) -> Logger { 50 | Logger { 51 | log_sculptor: LogSculptor::new(config.record_format), 52 | level_filter: config.level, 53 | log_painter: LogPainter::new(config.theme, config.color_format), 54 | log_writer: LogWriter::new(config.use_stderr), 55 | } 56 | } 57 | 58 | /// Initialize this logger 59 | pub fn init(self) -> Result<(), SetLoggerError> { 60 | log::set_boxed_logger(Box::new(self)).map(|()| log::set_max_level(LevelFilter::Trace)) 61 | } 62 | } 63 | 64 | impl Log for Logger { 65 | /// Check if this message should be logged 66 | fn enabled(&self, metadata: &Metadata) -> bool { 67 | metadata.level() <= self.level_filter 68 | } 69 | 70 | /// Log a message/record 71 | /// 72 | /// # Arguments 73 | /// 74 | /// * `record` - the record to log 75 | fn log(&self, record: &Record) { 76 | if !self.enabled(record.metadata()) { 77 | return; 78 | } 79 | 80 | let mut msg = self.log_sculptor.sculpt(record); 81 | msg = self.log_painter.paint(msg, record.level()); 82 | self.log_writer.write(msg, record.level()); 83 | } 84 | 85 | fn flush(&self) {} 86 | } 87 | 88 | #[cfg(test)] 89 | mod tests { 90 | use super::*; 91 | use log::Level; 92 | 93 | #[test] 94 | fn enabled_filters_levels() { 95 | let config = Config { 96 | level: LevelFilter::Warn, 97 | ..Default::default() 98 | }; 99 | let logger = Logger::with_config(config); 100 | let mut mb = Metadata::builder(); 101 | 102 | assert!(!logger.enabled(&mut mb.level(Level::Trace).build())); 103 | assert!(!logger.enabled(&mut mb.level(Level::Debug).build())); 104 | assert!(!logger.enabled(&mut mb.level(Level::Info).build())); 105 | assert!(logger.enabled(&mut mb.level(Level::Warn).build())); 106 | assert!(logger.enabled(&mut mb.level(Level::Error).build())); 107 | } 108 | 109 | #[test] 110 | fn enabled_with_off_level_filter_is_always_false() { 111 | let config = Config { 112 | level: LevelFilter::Off, 113 | ..Default::default() 114 | }; 115 | let logger = Logger::with_config(config); 116 | let mut mb = Metadata::builder(); 117 | 118 | assert!(!logger.enabled(&mut mb.level(Level::Trace).build())); 119 | assert!(!logger.enabled(&mut mb.level(Level::Debug).build())); 120 | assert!(!logger.enabled(&mut mb.level(Level::Info).build())); 121 | assert!(!logger.enabled(&mut mb.level(Level::Warn).build())); 122 | assert!(!logger.enabled(&mut mb.level(Level::Error).build())); 123 | } 124 | 125 | #[test] 126 | fn log_handles_empty_record() { 127 | let config = Config::default(); 128 | let logger = Logger::with_config(config); 129 | 130 | // create record with fields set to empty strings 131 | let rec = Record::builder() 132 | .args(format_args!("")) 133 | .level(Level::Info) 134 | .target("") 135 | .build(); 136 | 137 | // this shouldn't panic 138 | logger.log(&rec); 139 | } 140 | } 141 | -------------------------------------------------------------------------------- /src/paint.rs: -------------------------------------------------------------------------------- 1 | use crate::{Rgb, RgbRange, Theme}; 2 | use colored::Colorize; 3 | use log::Level; 4 | use std::collections::HashMap; 5 | use std::sync::Mutex; 6 | use unicode_segmentation::UnicodeSegmentation; 7 | 8 | /// Color formatting mode that determines how log records are colored/how a theme 9 | /// is applied to log records 10 | pub enum ColorFormat { 11 | /// solid color(s) applied from a theme to log lines 12 | Solid, 13 | /// linear color gradient applied over characters in a single line, with arg for number of steps 14 | /// in gradient (how many characters it will take to go from the starting color to the ending color 15 | /// for each level) 16 | InlineGradient(usize), 17 | /// linear color gradient applied over multiple lines, with arg for number of steps in gradient (how 18 | /// many lines it will take to go from the starting color to the ending color for each level) 19 | MultiLineGradient(usize), 20 | } 21 | 22 | /// Get the distance, [0-1], that `x` falls along the line from 0-`n` 23 | /// 24 | /// Dist will move in the direction: 25 | /// - 0 -> 1 when (`x` % `2n`) <= `n` 26 | /// - 1 -> 0 when `n` < (`x` % `2n`) < `2n` 27 | /// 28 | /// If used with linear gradients, this oscillating dist will avoid the harsh visual 29 | /// transition when wrapping around from 1 -> 0 (e.g. 0.9, 1.0, 0.0, 0.1 will not be 30 | /// a smooth transition) 31 | /// 32 | /// # Arguments 33 | /// 34 | /// * `x` - some number whose value, `x` % `2n`, will be considered the distance along the line 0-`n` 35 | /// * `n` - upper limit of range 0-`n` 36 | fn oscillate_dist(x: usize, n: usize) -> f32 { 37 | let n = if n == 0 { 1 } else { n }; 38 | (x.wrapping_add(n) % n.wrapping_mul(2)).abs_diff(n) as f32 / (n as f32) 39 | } 40 | 41 | /// Compute a new color `dist` distance along the linear 42 | /// gradient from start to end of `range` 43 | /// 44 | /// `dist` will be clamped to the range 0.0 - 1.0 45 | /// 46 | /// # Arguments 47 | /// 48 | /// * `range` - bounding color range for this linear gradient 49 | /// * `dist` - desired distance along linear gradient (0.0 - 1.0) 50 | fn linear_gradient(range: &RgbRange, dist: f32) -> Rgb { 51 | let dist = dist.clamp(0.0, 1.0); 52 | let start = &range.start; 53 | let end = &range.end; 54 | 55 | let r_range = (end.r as f32) - (start.r as f32); 56 | let g_range = (end.g as f32) - (start.g as f32); 57 | let b_range = (end.b as f32) - (start.b as f32); 58 | 59 | Rgb { 60 | r: ((start.r as f32) + (dist * r_range)) as u8, 61 | g: ((start.g as f32) + (dist * g_range)) as u8, 62 | b: ((start.b as f32) + (dist * b_range)) as u8, 63 | } 64 | } 65 | 66 | /// Paint/color logs using arbitrary themes and formats 67 | pub struct LogPainter { 68 | /// Count of how many lines are logged at each level, 69 | /// for use with coloring 70 | lines_logged: Mutex>, 71 | /// color theme (determines the color palette used to color log records) 72 | theme: Box, 73 | /// color formatting mode (determines how log records are colored) 74 | color_format: Option, 75 | } 76 | 77 | impl LogPainter { 78 | /// Create a new LogPainter 79 | /// 80 | /// # Arguments 81 | /// 82 | /// * `theme` - theme used for color selection 83 | /// * `color_format` - format used for painting 84 | pub fn new(theme: Box, color_format: Option) -> LogPainter { 85 | LogPainter { 86 | lines_logged: Mutex::new(HashMap::new()), 87 | theme, 88 | color_format, 89 | } 90 | } 91 | 92 | /// Paint/color a log line, based on the current logger configuration 93 | /// 94 | /// Arguments 95 | /// 96 | /// * `msg` - message to paint/color 97 | /// * `level` - level of this log line 98 | pub fn paint(&self, msg: String, level: Level) -> String { 99 | if self.color_format.is_none() { 100 | return msg; 101 | } 102 | 103 | let line = match self.color_format.as_ref().unwrap() { 104 | ColorFormat::Solid => self.paint_solid(msg, level), 105 | ColorFormat::InlineGradient(steps) => self.paint_inline_gradient(msg, level, *steps), 106 | ColorFormat::MultiLineGradient(steps) => { 107 | let l = self.paint_multi_line_gradient(msg, level, *steps); 108 | 109 | // increment line counter for this level 110 | self.lines_logged 111 | .lock() 112 | .unwrap() 113 | .entry(level) 114 | .and_modify(|e| *e = e.wrapping_add(1)) 115 | .or_insert(0); 116 | 117 | return l; 118 | } 119 | }; 120 | 121 | return line; 122 | } 123 | 124 | /// Paint strings using one color per line, 125 | /// chosen based on log level 126 | /// 127 | /// # Arguments 128 | /// 129 | /// * `msg` - message to color 130 | /// * `level` - level of this log line 131 | fn paint_solid(&self, msg: String, level: Level) -> String { 132 | let color = self.theme.solid(level); 133 | msg.color(color).to_string() 134 | } 135 | 136 | /// Apply linear color gradient across the graphemes in a string 137 | /// 138 | /// # Arguments 139 | /// 140 | /// * `msg` - message to color 141 | /// * `level` - level of this log line 142 | /// * `steps` - number of steps in gradient 143 | fn paint_inline_gradient(&self, msg: String, level: Level, steps: usize) -> String { 144 | msg.graphemes(true) 145 | .enumerate() 146 | .map(|(i, c)| { 147 | let dist = oscillate_dist(i, steps); 148 | let color = linear_gradient(&self.theme.range(level), dist); 149 | c.color(color).to_string() 150 | }) 151 | .collect::>() 152 | .join("") 153 | } 154 | 155 | /// Apply a linear color gradient over multiple lines 156 | /// 157 | /// An independent linear color gradient will be applied across 158 | /// all lines logged at each level (e.g. `INFO` line color can change 159 | /// from green -> cyan as lines are logged, while lines logged at other 160 | /// levels move independently in their own gradient color ranges) 161 | /// 162 | /// # Arguments 163 | /// 164 | /// * `msg` - message to color 165 | /// * `level` - level of this log line 166 | /// * `steps` - number of steps in gradient 167 | fn paint_multi_line_gradient(&self, msg: String, level: Level, steps: usize) -> String { 168 | let lines_logged = *self.lines_logged.lock().unwrap().entry(level).or_insert(0); 169 | let dist = oscillate_dist(lines_logged, steps); 170 | let color = linear_gradient(&self.theme.range(level), dist); 171 | msg.color(color).to_string() 172 | } 173 | } 174 | 175 | #[cfg(test)] 176 | mod tests { 177 | use super::*; 178 | use crate::theme; 179 | use num::NumCast; 180 | 181 | // helpers 182 | 183 | /// Assert that two values are equal within some range, `eps` 184 | /// 185 | /// # Arguments 186 | /// 187 | /// * `a` - first value to compare 188 | /// * `b` - second value to compare 189 | /// * `eps` - max distance to consider diff of values equal within 190 | fn assert_eq_with_eps(a: T, b: T, eps: T) { 191 | let a: f64 = NumCast::from(a).unwrap(); 192 | let b: f64 = NumCast::from(b).unwrap(); 193 | let eps: f64 = NumCast::from(eps).unwrap(); 194 | 195 | if (a - b).abs() > eps { 196 | panic!("{} and {} were not equal", a, b); 197 | } 198 | } 199 | 200 | /// To account for differences in the floating point math used to 201 | /// calculate colors along a gradient, this function compares the 202 | /// values in two Rgb structs within some range (+/- some value) 203 | /// 204 | /// # Arguments 205 | /// 206 | /// * `lhs` - first color in comparison 207 | /// * `rhs` - second color in comparison 208 | /// * `eps` - max distance to consider diff of r/g/b values equal within 209 | fn assert_rgb_eq(lhs: Rgb, rhs: Rgb, eps: Option) { 210 | let eps = eps.unwrap_or(1); 211 | 212 | assert_eq_with_eps(lhs.r, rhs.r, eps); 213 | assert_eq_with_eps(lhs.g, rhs.g, eps); 214 | assert_eq_with_eps(lhs.b, rhs.b, eps); 215 | } 216 | 217 | /// Assert that `f` gives a uniquely colored output for a string 218 | /// logged at each of the possible log levels 219 | /// 220 | /// # Arguments 221 | /// 222 | /// * `f` - function to color a string by log level 223 | fn assert_logs_colored_by_level(f: &dyn Fn(&LogPainter, String, Level) -> String) { 224 | // create a painter 225 | let theme = Box::new(theme::Simple {}); 226 | let painter = LogPainter::new(theme, Some(ColorFormat::Solid)); 227 | 228 | // run `f` on `msg` with each level to make sure that 229 | // no two levels give the same colored output 230 | let msg = "foo".to_string(); 231 | let lines = [ 232 | f(&painter, msg.clone(), Level::Trace), 233 | f(&painter, msg.clone(), Level::Debug), 234 | f(&painter, msg.clone(), Level::Info), 235 | f(&painter, msg.clone(), Level::Warn), 236 | f(&painter, msg.clone(), Level::Error), 237 | ]; 238 | 239 | // check that each colored line is unique 240 | for (i, line) in lines.iter().enumerate() { 241 | for line1 in lines.iter().skip(i + 1) { 242 | if line == line1 { 243 | panic!("\"{}\" and \"{}\" had different levels but generated the same formatted line", line, line1); 244 | } 245 | } 246 | } 247 | } 248 | 249 | // tests 250 | 251 | #[test] 252 | fn linear_gradient_calculates_correct_color() { 253 | let r = RgbRange { 254 | start: Rgb { r: 0, g: 0, b: 0 }, 255 | end: Rgb { 256 | r: 255, 257 | g: 255, 258 | b: 255, 259 | }, 260 | }; 261 | 262 | assert_rgb_eq(linear_gradient(&r, 0.0), Rgb { r: 0, g: 0, b: 0 }, None); 263 | assert_rgb_eq( 264 | linear_gradient(&r, 0.25), 265 | Rgb { 266 | r: 64, 267 | g: 64, 268 | b: 64, 269 | }, 270 | None, 271 | ); 272 | assert_rgb_eq( 273 | linear_gradient(&r, 0.5), 274 | Rgb { 275 | r: 128, 276 | g: 128, 277 | b: 128, 278 | }, 279 | None, 280 | ); 281 | assert_rgb_eq( 282 | linear_gradient(&r, 0.75), 283 | Rgb { 284 | r: 190, 285 | g: 190, 286 | b: 190, 287 | }, 288 | None, 289 | ); 290 | assert_rgb_eq( 291 | linear_gradient(&r, 1.0), 292 | Rgb { 293 | r: 255, 294 | g: 255, 295 | b: 255, 296 | }, 297 | None, 298 | ); 299 | } 300 | 301 | #[test] 302 | fn linear_gradient_clamps_dist() { 303 | let r = RgbRange { 304 | start: Rgb { r: 0, g: 0, b: 0 }, 305 | end: Rgb { 306 | r: 255, 307 | g: 255, 308 | b: 255, 309 | }, 310 | }; 311 | 312 | let expected = Rgb { r: 0, g: 0, b: 0 }; 313 | assert_rgb_eq(linear_gradient(&r, -1.0), expected, None); 314 | 315 | let expected = Rgb { 316 | r: 255, 317 | g: 255, 318 | b: 255, 319 | }; 320 | assert_rgb_eq(linear_gradient(&r, 100.0), expected, None); 321 | } 322 | 323 | #[test] 324 | fn oscillate_dist_oscillates() { 325 | assert_eq_with_eps(oscillate_dist(0, 255), 0.0, 1e-2); 326 | assert_eq_with_eps(oscillate_dist(128, 255), 0.5, 1e-2); 327 | assert_eq_with_eps(oscillate_dist(255, 255), 1.0, 1e-2); 328 | assert_eq_with_eps(oscillate_dist(256, 255), 1.0 - (1.0 / 255.0), 1e-2); 329 | assert_eq_with_eps(oscillate_dist(383, 255), 0.5, 1e-2); 330 | assert_eq_with_eps(oscillate_dist(510, 255), 0.0, 1e-2); 331 | assert_eq_with_eps(oscillate_dist(638, 255), 0.5, 1e-2); 332 | assert_eq_with_eps(oscillate_dist(765, 255), 1.0, 1e-2); 333 | assert_eq_with_eps( 334 | oscillate_dist(usize::max_value(), 255), 335 | oscillate_dist(usize::max_value() - 255, 255), 336 | 1e-2, 337 | ); 338 | assert_eq_with_eps(oscillate_dist(12, usize::max_value()), 1.0, 1e-2); 339 | assert_eq_with_eps(oscillate_dist(257, usize::max_value()), 1.0, 1e-2); 340 | assert_eq_with_eps( 341 | oscillate_dist(usize::max_value(), usize::max_value()), 342 | 1.0, 343 | 1e-2, 344 | ); 345 | } 346 | 347 | #[test] 348 | fn oscillate_dist_handles_0_n() { 349 | // this shouldn't panic 350 | oscillate_dist(0, 0); 351 | } 352 | 353 | #[test] 354 | fn paint_solid_colors_by_level() { 355 | assert_logs_colored_by_level(&LogPainter::paint_solid); 356 | } 357 | 358 | #[test] 359 | fn paint_inline_gradient_colors_by_level() { 360 | let color_fn = |painter: &LogPainter, msg: String, level: Level| -> String { 361 | painter.paint_inline_gradient(msg, level, 20) 362 | }; 363 | 364 | assert_logs_colored_by_level(&color_fn); 365 | } 366 | 367 | #[test] 368 | fn paint_multi_line_gradient_colors_by_level() { 369 | let color_fn = |painter: &LogPainter, msg: String, level: Level| -> String { 370 | painter.paint_multi_line_gradient(msg, level, 20) 371 | }; 372 | 373 | assert_logs_colored_by_level(&color_fn); 374 | } 375 | 376 | #[test] 377 | fn paint_fns_handle_empty_msg() { 378 | let theme = Box::new(theme::Simple {}); 379 | let color_format = Some(ColorFormat::Solid); 380 | let painter = LogPainter::new(theme, color_format); 381 | 382 | // none of these calls should panic with an empty message 383 | painter.paint_solid("".to_string(), Level::Warn); 384 | painter.paint_inline_gradient("".to_string(), Level::Warn, 10); 385 | painter.paint_multi_line_gradient("".to_string(), Level::Warn, 10); 386 | } 387 | 388 | #[test] 389 | fn paint_with_none_format_returns_orig() { 390 | let theme = Box::new(theme::Simple {}); 391 | let color_format = None; 392 | let painter = LogPainter::new(theme, color_format); 393 | 394 | // input msg should not be altered by None color format 395 | let msg = "foo".to_string(); 396 | assert_eq!(painter.paint(msg.clone(), Level::Info), msg); 397 | } 398 | 399 | #[test] 400 | fn paint_log_with_inline_gradient_uses_steps_arg() { 401 | let theme = Box::new(theme::Simple {}); 402 | let color_format = Some(ColorFormat::InlineGradient(2)); 403 | let painter = LogPainter::new(theme, color_format); 404 | let msgs = vec!["0000000000".to_string(), "नमस्तेनमस्तेनमस्तेनमस्तेनमस्ते".to_string()]; 405 | 406 | for msg in msgs { 407 | let msg_colored = painter.paint(msg.clone(), Level::Info); 408 | 409 | // collect ANSI 24-bit escape sequences to compare color of each grapheme 410 | let words = msg_colored.unicode_words().collect::>(); 411 | let num_words = words.len(); 412 | let graphemes = msg.graphemes(true).collect::>().len(); 413 | let escape_seqs = words 414 | .into_iter() 415 | .step_by(num_words / graphemes) 416 | .collect::>(); 417 | 418 | // check that gradient restarts at index 4 (2 * steps) 419 | // 420 | // it restarts at 4 instead of 2 because the gradient is first 421 | // traversed from start to end, then from end to start, then start to end 422 | // again, oscillating this way indefinitely 423 | assert_ne!(escape_seqs[0], escape_seqs[1]); 424 | assert_eq!(escape_seqs[0], escape_seqs[4]); 425 | assert_eq!(escape_seqs[1], escape_seqs[5]); 426 | assert_eq!(escape_seqs[2], escape_seqs[6]); 427 | assert_eq!(escape_seqs[3], escape_seqs[7]); 428 | } 429 | } 430 | 431 | #[test] 432 | fn paint_log_with_multi_line_gradient_changes_color_within_level() { 433 | let theme = Box::new(theme::Simple {}); 434 | let color_format = Some(ColorFormat::MultiLineGradient(20)); 435 | let painter = LogPainter::new(theme, color_format); 436 | let msg = "foo".to_string(); 437 | 438 | // the color should change each time a message is logged, 439 | // since the multi-line gradient color format should create 440 | // a color gradient over multiple lines (under each level) 441 | let assert_color_changes_within_level = |level: Level| { 442 | let mut last_logged = "".to_string(); 443 | 444 | for _ in 0..10 { 445 | let l = painter.paint(msg.clone(), level); 446 | assert_ne!(last_logged, l); 447 | last_logged = l; 448 | } 449 | }; 450 | 451 | assert_color_changes_within_level(Level::Trace); 452 | assert_color_changes_within_level(Level::Debug); 453 | assert_color_changes_within_level(Level::Info); 454 | assert_color_changes_within_level(Level::Warn); 455 | assert_color_changes_within_level(Level::Error); 456 | } 457 | 458 | #[test] 459 | fn paint_log_with_multi_line_gradient_uses_steps_arg() { 460 | // use multi-line gradient with 2 steps in the linear gradient 461 | let steps: usize = 2; 462 | let theme = Box::new(theme::Simple {}); 463 | let color_format = Some(ColorFormat::MultiLineGradient(steps)); 464 | let painter = LogPainter::new(theme, color_format); 465 | let msg = "foo".to_string(); 466 | 467 | let lines = vec![ 468 | // gradient starts going from start -> end here 469 | painter.paint(msg.clone(), Level::Info), 470 | painter.paint(msg.clone(), Level::Info), 471 | // end -> start 472 | painter.paint(msg.clone(), Level::Info), 473 | painter.paint(msg.clone(), Level::Info), 474 | // gradient should start over here, start -> end 475 | painter.paint(msg.clone(), Level::Info), 476 | painter.paint(msg.clone(), Level::Info), 477 | // end -> start 478 | painter.paint(msg.clone(), Level::Info), 479 | painter.paint(msg.clone(), Level::Info), 480 | ]; 481 | 482 | // check that gradient restarts at index 4 (2 * steps) 483 | // 484 | // it restarts at 4 instead of 2 because the gradient is first 485 | // traversed from start to end, then from end to start, then start to end 486 | // again, oscillating this way indefinitely 487 | assert_ne!(lines[0], lines[1]); 488 | assert_eq!(lines[0], lines[4]); 489 | assert_eq!(lines[1], lines[5]); 490 | assert_eq!(lines[2], lines[6]); 491 | assert_eq!(lines[3], lines[7]); 492 | } 493 | } 494 | -------------------------------------------------------------------------------- /src/sculpt.rs: -------------------------------------------------------------------------------- 1 | use log::Record; 2 | use serde_json::json; 3 | use time::format_description::well_known::Iso8601; 4 | use time::OffsetDateTime; 5 | 6 | /// Record formatting mode that determines how log records are structured 7 | pub enum RecordFormat { 8 | /// JSON format 9 | Json, 10 | /// simple log format ` [] - ` 11 | Simple, 12 | /// custom record formatter provided by client code 13 | Custom(Box String>), 14 | } 15 | 16 | /// Sculpt/create structurally formatted string logs from raw log records 17 | pub struct LogSculptor { 18 | /// record formatting mode (determines how log records are structurally formatted) 19 | pub record_format: RecordFormat, 20 | } 21 | 22 | impl LogSculptor { 23 | /// Create a new LogSculptor using the provided record format 24 | /// 25 | /// # Arguments 26 | /// 27 | /// * `record_format` - the structural format to use when sculpting records 28 | pub fn new(record_format: RecordFormat) -> LogSculptor { 29 | LogSculptor { record_format } 30 | } 31 | 32 | /// Convert a log record into a formatted string, based on the current logger configuration 33 | /// 34 | /// # Arguments 35 | /// 36 | /// * `record` - the log record to format 37 | pub fn sculpt(&self, record: &Record) -> String { 38 | let now = OffsetDateTime::now_utc() 39 | .format(&Iso8601::DEFAULT) 40 | .expect("Failed to format time as ISO 8601"); 41 | 42 | match &self.record_format { 43 | RecordFormat::Json => json!({ 44 | "time": now, 45 | "level": record.level(), 46 | "target": record.target(), 47 | "message": record.args(), 48 | }) 49 | .to_string(), 50 | RecordFormat::Simple => { 51 | format!( 52 | "{} [{}] {} - {}", 53 | now, 54 | record.target(), 55 | record.level(), 56 | record.args() 57 | ) 58 | } 59 | RecordFormat::Custom(f) => f(record), 60 | } 61 | } 62 | } 63 | 64 | #[cfg(test)] 65 | mod tests { 66 | use super::*; 67 | use log::Level; 68 | 69 | #[test] 70 | fn sculpt_presets_return_non_empty() { 71 | for fmt in vec![RecordFormat::Json, RecordFormat::Simple] { 72 | let sculptor = LogSculptor::new(fmt); 73 | 74 | // create normal test record 75 | let rec = Record::builder() 76 | .args(format_args!("foo")) 77 | .level(Level::Info) 78 | .target("test") 79 | .build(); 80 | 81 | assert!(!sculptor.sculpt(&rec).is_empty()); 82 | 83 | // create record with empty args and target 84 | let rec = Record::builder() 85 | .args(format_args!("")) 86 | .level(Level::Info) 87 | .target("") 88 | .build(); 89 | 90 | // record should still give non-empty log lines 91 | assert!(!sculptor.sculpt(&rec).is_empty()); 92 | } 93 | } 94 | 95 | #[test] 96 | fn sculpt_custom_formats_correctly() { 97 | let test_cases = vec![ 98 | (RecordFormat::Custom(Box::new(|_| "".to_string())), ""), 99 | ( 100 | RecordFormat::Custom(Box::new(|r| format!("{} {}", r.level(), r.args()))), 101 | "INFO foo", 102 | ), 103 | ( 104 | RecordFormat::Custom(Box::new(|r| { 105 | format!("{} [{}] {}", r.level(), r.target(), r.args()) 106 | })), 107 | "INFO [test] foo", 108 | ), 109 | ]; 110 | 111 | let rec = Record::builder() 112 | .args(format_args!("foo")) 113 | .level(Level::Info) 114 | .target("test") 115 | .build(); 116 | 117 | for (fmt, expected) in test_cases { 118 | let sculptor = LogSculptor::new(fmt); 119 | assert_eq!(sculptor.sculpt(&rec), expected); 120 | } 121 | } 122 | } 123 | -------------------------------------------------------------------------------- /src/theme.rs: -------------------------------------------------------------------------------- 1 | //! Theme trait definition and predefined themes 2 | //! 3 | //! See examples/custom-theme.rs for an example of defining a 4 | //! custom theme 5 | 6 | use crate::color::{Color, Rgb, RgbRange}; 7 | use log::Level; 8 | 9 | /// Define a log level specific color palette to be injected into 10 | /// color formatting 11 | pub trait Theme: Send + Sync { 12 | /// return the representative solid color for this theme at each level 13 | fn solid(&self, level: Level) -> Rgb; 14 | /// return the bounding color range for this theme at each level 15 | fn range(&self, level: Level) -> RgbRange; 16 | } 17 | 18 | /// Basic log level colors 19 | #[derive(Clone)] 20 | pub struct Simple {} 21 | 22 | impl Theme for Simple { 23 | fn solid(&self, level: Level) -> Rgb { 24 | self.range(level).start 25 | } 26 | 27 | fn range(&self, level: Level) -> RgbRange { 28 | match level { 29 | Level::Trace => RgbRange { 30 | start: Color::DarkPink.value(), 31 | end: Color::Pink.value(), 32 | }, 33 | Level::Debug => RgbRange { 34 | start: Color::DarkCyan.value(), 35 | end: Color::Cyan.value(), 36 | }, 37 | Level::Info => RgbRange { 38 | start: Color::DarkGreen.value(), 39 | end: Color::Green.value(), 40 | }, 41 | Level::Warn => RgbRange { 42 | start: Color::DarkOrange.value(), 43 | end: Color::Orange.value(), 44 | }, 45 | Level::Error => RgbRange { 46 | start: Color::DarkRed.value(), 47 | end: Color::Red.value(), 48 | }, 49 | } 50 | } 51 | } 52 | 53 | /// Move down the color spectrum by level 54 | #[derive(Clone)] 55 | pub struct Spectral {} 56 | 57 | impl Theme for Spectral { 58 | fn solid(&self, level: Level) -> Rgb { 59 | self.range(level).end 60 | } 61 | 62 | fn range(&self, level: Level) -> RgbRange { 63 | match level { 64 | Level::Trace => RgbRange { 65 | start: Color::DarkMagenta.value(), 66 | end: Color::Pink.value(), 67 | }, 68 | Level::Debug => RgbRange { 69 | start: Color::DarkBlue.value(), 70 | end: Color::Cyan.value(), 71 | }, 72 | Level::Info => RgbRange { 73 | start: Color::DarkCyan.value(), 74 | end: Color::Green.value(), 75 | }, 76 | Level::Warn => RgbRange { 77 | start: Color::DarkYellow.value(), 78 | end: Color::Orange.value(), 79 | }, 80 | Level::Error => RgbRange { 81 | start: Color::DarkRed.value(), 82 | end: Color::Red.value(), 83 | }, 84 | } 85 | } 86 | } 87 | -------------------------------------------------------------------------------- /src/write.rs: -------------------------------------------------------------------------------- 1 | use colored::Colorize; 2 | use log::Level; 3 | use std::io; 4 | use std::io::Write; 5 | use std::sync::Mutex; 6 | 7 | /// Write logs to stdout/stderr with synchronization 8 | pub struct LogWriter { 9 | /// switch for enabling log splitting to `stderr` 10 | /// 11 | /// - `true`: log `trace` - `info` levels to `stdout` and `warn` - `error` levels to `stderr` 12 | /// 13 | /// - `false`: log all levels to `stdout` 14 | use_stderr: bool, 15 | /// guard against interleaving from simultaneous writes to stdout + stderr 16 | write_mtx: Mutex<()>, 17 | /// handle to stdout 18 | stdout: io::Stdout, 19 | /// handle to stderr 20 | stderr: io::Stderr, 21 | } 22 | 23 | impl LogWriter { 24 | /// Create a new LogWriter 25 | pub fn new(use_stderr: bool) -> LogWriter { 26 | LogWriter { 27 | use_stderr, 28 | write_mtx: Mutex::new(()), 29 | stdout: io::stdout(), 30 | stderr: io::stderr(), 31 | } 32 | } 33 | 34 | /// Write log message to output destination 35 | /// 36 | /// # Arguments 37 | /// 38 | /// * `msg` - the log message to write 39 | /// * `level` - the level of this log message 40 | pub fn write(&self, msg: String, level: Level) { 41 | // stdout and stderr already have their own locks, but 42 | // there is nothing preventing logs simultaneously written 43 | // to stdout + stderr from being interleaved in the console 44 | // 45 | // this guard synchronizes writes so that stdout will not be 46 | // interleaved with stderr 47 | let _lk = self.write_mtx.lock().unwrap(); 48 | 49 | match level { 50 | Level::Warn | Level::Error => { 51 | if self.use_stderr { 52 | let _ = writeln!(self.stderr.lock(), "{}", msg.bold()); 53 | } else { 54 | let _ = writeln!(self.stdout.lock(), "{}", msg.bold()); 55 | } 56 | } 57 | _ => { 58 | let _ = writeln!(self.stdout.lock(), "{}", msg); 59 | } 60 | }; 61 | } 62 | } 63 | 64 | #[cfg(test)] 65 | mod tests { 66 | use super::*; 67 | 68 | #[test] 69 | fn write_handles_empty_msg() { 70 | let levels = vec![ 71 | Level::Trace, 72 | Level::Debug, 73 | Level::Info, 74 | Level::Warn, 75 | Level::Error, 76 | ]; 77 | 78 | // using stderr 79 | let writer = LogWriter::new(true); 80 | 81 | for level in levels.iter() { 82 | writer.write("".to_string(), *level); 83 | } 84 | 85 | // not using stderr 86 | let writer = LogWriter::new(false); 87 | 88 | for level in levels.iter() { 89 | writer.write("".to_string(), *level); 90 | } 91 | } 92 | } 93 | --------------------------------------------------------------------------------