# sheen ✨
[](https://crates.io/crates/sheen)
[](https://docs.rs/sheen)
A polished, colorful logging library for Rust ✨

## Inspiration
sheen is inspired by [charmbracelet/log](https://github.com/charmbracelet/log), the excellent Go logging library. We wanted to bring the same polished experience to Rust.
## Features
- Colorful, human-readable output
- Structured key=value logging
- Multiple formatters: Text, JSON, Logfmt
- Sub-loggers with persistent fields
- TTY detection (auto-disables colors when piped)
- Builder pattern configuration
- Zero config defaults
- `log` crate compatibility (optional feature flag)
- `tracing` crate compatibility (optional feature flag)
## Installation
```toml
[dependencies]
sheen = "0.3"
```
With `log` crate support:
```toml
[dependencies]
sheen = { version = "0.3", features = ["log"] }
```
With `tracing` crate support:
```toml
[dependencies]
sheen = { version = "0.3", features = ["tracing"] }
```
## Quick Start
```rust
fn main() {
sheen::init();
sheen::info!("Server started", port = 3000);
sheen::debug!("Loading config");
sheen::warn!("Cache miss", key = "user_123");
sheen::error!("Connection failed", attempts = 3);
}
```
Output:
```
14:32:15 INFO Server started port=3000
14:32:15 WARN Cache miss key="user_123"
14:32:15 ERROR Connection failed attempts=3
```
## Custom Configuration
```rust
use sheen::{Logger, Level};
fn main() {
sheen::init_with(
Logger::new()
.level(Level::Trace)
.prefix("myapp")
.timestamp(true)
);
sheen::trace!("verbose output");
sheen::info!("ready");
}
```
## Sub-loggers
Create loggers with persistent fields using `.with()`:
```rust
use sheen::{Logger, Level};
let logger = Logger::new().level(Level::Debug);
let req_log = logger.with(&[("request_id", &"abc123")]);
req_log.info("started", &[]);
req_log.info("db query", &[("table", &"users")]);
req_log.info("completed", &[("status", &200)]);
```
Output:
```
14:32:15 INFO started request_id="abc123"
14:32:15 INFO db query request_id="abc123" table="users"
14:32:15 INFO completed request_id="abc123" status=200
```
## Log Crate Integration
Enable the `log` feature to use sheen as a backend for the [`log`](https://crates.io/crates/log) crate. This captures logs from any dependency that uses `log::info!()`, `log::warn!()`, etc.
```rust
use sheen::{Logger, Level};
fn main() {
Logger::new()
.level(Level::Debug)
.init()
.unwrap();
// Standard log macros now go through sheen
log::info!("server started");
log::warn!("cache nearly full");
}
```
## Tracing Crate Integration
Enable the `tracing` feature to use sheen as a subscriber for the [`tracing`](https://crates.io/crates/tracing) crate. This captures events from any dependency that uses `tracing::info!()`, `tracing::warn!()`, etc.
```rust
use sheen::{Logger, Level, SheenLayer};
fn main() {
SheenLayer::new(Logger::new().level(Level::Trace)).init();
tracing::info!("server started");
tracing::warn!("cache nearly full");
}
```
## Formatters
### Text (default)
Colorful, human-readable output:
```rust
let logger = Logger::new();
logger.info("hello", &[("port", &3000)]);
// 14:32:15 INFO hello port=3000
```
### JSON
Structured output for log aggregators:
```rust
use sheen::{Logger, JsonFormatter};
let logger = Logger::new().formatter(JsonFormatter);
logger.info("hello", &[("port", &3000)]);
// {"level":"info","msg":"hello","time":"14:32:15","port":3000}
```
### Logfmt
Key=value format for Heroku, Splunk, etc:
```rust
use sheen::{Logger, LogfmtFormatter};
let logger = Logger::new().formatter(LogfmtFormatter);
logger.info("hello", &[("port", &3000)]);
// level=info msg="hello" time="14:32:15" port=3000
```
## TTY Detection
Colors are automatically disabled when output is piped:
```bash
# Colors enabled
cargo run
# Colors disabled (piped to file)
cargo run 2> logs.txt
```
Force colors on or off:
```rust
let logger = Logger::new().colorize(false);
```
## License
MIT