docs: add more docs (#29)

Signed-off-by: tison <[email protected]>

Cargo.toml

@@ -23,7 +23,7 @@ license = "Apache-2.0"
 readme = "README.md"
 repository = "https://github.com/tisonkun/logforth"
 rust-version = "1.71.0"
-version = "0.7.1"
+version = "0.7.2"
 
 [package.metadata.docs.rs]
 all-features = true

src/append/fastrace.rs

@@ -19,6 +19,7 @@ use log::Record;
 use crate::append::Append;
 use crate::layout::KvDisplay;
 
+/// An appender that adds log records to fastrace as an event associated to the current span.
 #[derive(Default, Debug, Clone)]
 pub struct FastraceEvent;
 

src/append/mod.rs

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! Dispatch log records to the appropriate target.
+
 use std::fmt;
 
 #[cfg(feature = "fastrace")]
@@ -41,7 +43,7 @@ pub trait Append: fmt::Debug + Send + Sync + 'static {
     /// Flushes any buffered records.
     fn flush(&self) {}
 
-    /// Default layout to use when [Dispatch][crate::logger::Dispatch] does not configure a
+    /// Default layout to use when [`Dispatch`][crate::logger::Dispatch] does not configure a
     /// preferred layout.
     fn default_layout(&self) -> Layout {
         Layout::Identical(IdenticalLayout)

src/append/opentelemetry.rs

@@ -28,6 +28,10 @@ use opentelemetry_sdk::logs::LoggerProvider;
 
 use crate::append::Append;
 
+/// The communication protocol to opentelemetry that used when exporting data.
+///
+/// This is a logical re-exported [`opentelemetry_otlp::Protocol`] to avoid version lock-in to
+/// `opentelemetry_otlp`.
 #[non_exhaustive]
 #[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum OpentelemetryWireProtocol {
@@ -36,6 +40,7 @@ pub enum OpentelemetryWireProtocol {
     HttpJson,
 }
 
+/// An appender that sends log records to opentelemetry.
 #[derive(Debug)]
 pub struct OpentelemetryLog {
     name: String,

src/append/rolling_file/append.rs

@@ -17,6 +17,8 @@ use log::Record;
 use crate::append::rolling_file::non_blocking::NonBlocking;
 use crate::append::Append;
 
+/// An appender that writes log records to a file that rolls over when it reaches a certain date
+/// time.
 #[derive(Debug)]
 pub struct RollingFile {
     writer: NonBlocking,

src/append/stdio.rs

@@ -16,6 +16,7 @@ use std::io::Write;
 
 use crate::append::Append;
 
+/// An appender that prints log records to stdout.
 #[derive(Default, Debug)]
 pub struct Stdout;
 
@@ -31,6 +32,7 @@ impl Append for Stdout {
     }
 }
 
+/// An appender that prints log records to stderr.
 #[derive(Default, Debug)]
 pub struct Stderr;
 

src/filter/custom.rs

@@ -19,6 +19,24 @@ use log::Metadata;
 use crate::filter::Filter;
 use crate::filter::FilterResult;
 
+/// A filter that you can pass the custom filter function.
+///
+/// The custom filter function accepts [`&log::Metadata`][Metadata] and returns the
+/// [`FilterResult`]. For example:
+///
+/// ```rust
+/// use log::Metadata;
+/// use logforth::filter::CustomFilter;
+/// use logforth::filter::FilterResult;
+///
+/// let filter = CustomFilter::new(|metadata: &Metadata| {
+///     if metadata.target() == "my_crate" {
+///         FilterResult::Accept
+///     } else {
+///         FilterResult::Neutral
+///     }
+/// });
+/// ```
 pub struct CustomFilter {
     f: Box<dyn Fn(&Metadata) -> FilterResult + Send + Sync + 'static>,
 }

src/filter/mod.rs

@@ -12,12 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! Determinate whether a log record should be processed.
+
 pub use self::custom::CustomFilter;
 pub use self::level::LevelFilter;
 
 mod custom;
 mod level;
 
+/// The result of a filter may return.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum FilterResult {
     /// The record will be processed without further filtering.

src/layout/custom.rs

@@ -27,6 +27,23 @@ type FormatFunction = dyn Fn(&Record, &dyn Fn(Arguments) -> anyhow::Result<()>)
     + Sync
     + 'static;
 
+/// A layout that you can pass the custom layout function.
+///
+/// The custom layout function accepts [`&log::Record`][Record], formats it into [Arguments], and
+/// then passes to the closure. For example:
+///
+/// ```rust
+/// use std::fmt::Arguments;
+///
+/// use log::Record;
+/// use logforth::layout::CustomLayout;
+///
+/// let layout = CustomLayout::new(
+///     |record: &Record, f: &dyn Fn(Arguments) -> anyhow::Result<()>| {
+///         f(format_args!("{} - {}", record.level(), record.args()))
+///     },
+/// );
+/// ```
 pub struct CustomLayout {
     f: Box<FormatFunction>,
 }

src/layout/identical.rs

@@ -16,6 +16,10 @@ use std::fmt::Arguments;
 
 use crate::layout::Layout;
 
+/// A layout that returns log record as is.
+///
+/// This is mainly used as the default implementation for
+/// [`Append::default_layout`][crate::append::Append::default_layout].
 #[derive(Debug, Default, Clone, Copy)]
 pub struct IdenticalLayout;
 

src/layout/json.rs

@@ -23,6 +23,17 @@ use serde_json::Value;
 
 use crate::layout::Layout;
 
+/// A layout that formats log record as JSON lines.
+///
+/// Output format:
+///
+/// ```json
+/// {"timestamp":"2024-08-01T13:57:05.099261Z","level":"ERROR","module_path":"rolling_file","file":"rolling_file.rs","line":48,"message":"Hello error!","kvs":{}}
+/// {"timestamp":"2024-08-01T13:57:05.099313Z","level":"WARN","module_path":"rolling_file","file":"rolling_file.rs","line":49,"message":"Hello warn!","kvs":{}}
+/// {"timestamp":"2024-08-01T13:57:05.099338Z","level":"INFO","module_path":"rolling_file","file":"rolling_file.rs","line":50,"message":"Hello info!","kvs":{}}
+/// {"timestamp":"2024-08-01T13:57:05.099362Z","level":"DEBUG","module_path":"rolling_file","file":"rolling_file.rs","line":51,"message":"Hello debug!","kvs":{}}
+/// {"timestamp":"2024-08-01T13:57:05.099386Z","level":"TRACE","module_path":"rolling_file","file":"rolling_file.rs","line":52,"message":"Hello trace!","kvs":{}}
+/// ```
 #[derive(Default, Debug, Clone)]
 pub struct JsonLayout;
 

src/layout/kv.rs

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+/// A helper struct to format log's key-value pairs.
 pub struct KvDisplay<'kvs> {
     kv: &'kvs dyn log::kv::Source,
 }

src/layout/mod.rs

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! Describe how to format a log record.
+
 pub use custom::CustomLayout;
 pub use identical::IdenticalLayout;
 #[cfg(feature = "json")]
@@ -27,6 +29,7 @@ mod json;
 mod kv;
 mod text;
 
+/// A layout describes how to format a log record.
 #[derive(Debug)]
 pub enum Layout {
     Identical(IdenticalLayout),

src/layout/text.rs

@@ -23,11 +23,29 @@ use log::Level;
 use crate::layout::KvDisplay;
 use crate::layout::Layout;
 
+/// A layout that formats log record as text.
+///
+/// Output format:
+///
+/// ```text
+/// 2024-08-02T12:49:03.102343Z ERROR simple_stdio: examples/simple_stdio.rs:32 Hello error!
+/// 2024-08-02T12:49:03.102442Z  WARN simple_stdio: examples/simple_stdio.rs:33 Hello warn!
+/// 2024-08-02T12:49:03.102447Z  INFO simple_stdio: examples/simple_stdio.rs:34 Hello info!
+/// 2024-08-02T12:49:03.102450Z DEBUG simple_stdio: examples/simple_stdio.rs:35 Hello debug!
+/// 2024-08-02T12:49:03.102453Z TRACE simple_stdio: examples/simple_stdio.rs:36 Hello trace!
+/// ```
+///
+/// By default, log levels are colored. You can turn on the `no-color` feature flag to disable this
+/// feature.
+///
+/// You can also customize the color of each log level by setting the `colors` field with a
+/// [`LevelColor`] instance.
 #[derive(Default, Debug, Clone)]
 pub struct TextLayout {
     pub colors: LevelColor,
 }
 
+/// Customize the color of each log level.
 #[derive(Debug, Clone)]
 pub struct LevelColor {
     pub error: Color,

src/lib.rs

@@ -12,6 +12,47 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+//! # A versatile and extensible logging implementation
+//!
+//! ## Usage
+//!
+//! Add the dependencies to your `Cargo.toml` with:
+//!
+//! ```shell
+//! cargo add log
+//! cargo add logforth
+//! ```
+//!
+//! Here, [`log`] is the logging facade and `logforth` is the logging implementation.
+//!
+//! Then, you can use the logger with:
+//!
+//! ```rust
+//! use log::LevelFilter;
+//! use logforth::append;
+//! use logforth::layout::TextLayout;
+//! use logforth::Dispatch;
+//! use logforth::Logger;
+//!
+//! Logger::new()
+//!     .dispatch(
+//!         Dispatch::new()
+//!             .filter(LevelFilter::Trace)
+//!             .layout(TextLayout::default())
+//!             .append(append::Stdout),
+//!     )
+//!     .apply()
+//!     .unwrap();
+//!
+//! log::error!("Hello error!");
+//! log::warn!("Hello warn!");
+//! log::info!("Hello info!");
+//! log::debug!("Hello debug!");
+//! log::trace!("Hello trace!");
+//! ```
+//!
+//! Read more demos under the [examples](https://github.com/tisonkun/logforth/tree/main/examples) directory.
+
 pub mod append;
 pub mod filter;
 pub mod layout;

src/logger.rs

@@ -25,12 +25,12 @@ use crate::layout::Layout;
 
 /// A grouped set of appenders, filters, and optional layout.
 ///
-/// The [Logger] facade dispatches log records to one or more [Dispatch] instances.
-/// Each [Dispatch] instance contains a set of filters, appenders, and an optional layout.
+/// The [`Logger`] facade dispatches log records to one or more [`Dispatch`] instances.
+/// Each [`Dispatch`] instance contains a set of filters, appenders, and an optional layout.
 ///
 /// `filters` are used to determine whether a log record should be passed to the appenders.
 /// `appends` are used to write log records to a destination. Each appender has its own
-/// default layout. If the [Dispatch] has a layout, it will be used instead of the default layout.
+/// default layout. If the [`Dispatch`] has a layout, it will be used instead of the default layout.
 #[derive(Debug)]
 pub struct Dispatch<const LAYOUT: bool = true, const APPEND: bool = true> {
     filters: Vec<Filter>,
@@ -45,9 +45,9 @@ impl Default for Dispatch<false, false> {
 }
 
 impl Dispatch<false, false> {
-    /// Create a new incomplete [Dispatch] instance.
+    /// Create a new incomplete [`Dispatch`] instance.
     ///
-    /// At least one append must be added to the [Dispatch] before it can be used.
+    /// At least one append must be added to the [`Dispatch`] before it can be used.
     pub fn new() -> Dispatch<false, false> {
         Self {
             filters: vec![],
@@ -56,14 +56,14 @@ impl Dispatch<false, false> {
         }
     }
 
-    /// Add a [Filter] to the [Dispatch].
+    /// Add a [`Filter`] to the [`Dispatch`].
     pub fn filter(mut self, filter: impl Into<Filter>) -> Dispatch<false, false> {
         self.filters.push(filter.into());
         self
     }
 
-    /// Add the preferred [Layout] to the [Dispatch]. At most one layout can be added to a
-    /// [Dispatch].
+    /// Add the preferred [`Layout`] to the [`Dispatch`]. At most one layout can be added to a
+    /// [`Dispatch`].
     pub fn layout(self, layout: impl Into<Layout>) -> Dispatch<true, false> {
         Dispatch {
             filters: self.filters,
@@ -74,7 +74,7 @@ impl Dispatch<false, false> {
 }
 
 impl<const LAYOUT: bool, const APPEND: bool> Dispatch<LAYOUT, APPEND> {
-    /// Add an [Append] to the [Dispatch].
+    /// Add an [`Append`] to the [`Dispatch`].
     pub fn append(mut self, append: impl Append) -> Dispatch<true, true> {
         self.appends.push(Box::new(append));
 
@@ -119,10 +119,10 @@ impl Dispatch {
     }
 }
 
-/// A logger facade that dispatches log records to one or more [Dispatch] instances.
+/// A logger facade that dispatches log records to one or more [`Dispatch`] instances.
 ///
-/// This struct implements [log::Log] to bridge Logforth's logging implementations
-/// with the [log] crate.
+/// This struct implements [`log::Log`] to bridge Logforth's logging implementations
+/// with the [`log`] crate.
 #[derive(Debug)]
 pub struct Logger {
     dispatches: Vec<Dispatch>,
@@ -135,20 +135,20 @@ impl Default for Logger {
 }
 
 impl Logger {
-    /// Create a new [Logger] instance.
+    /// Create a new [`Logger`] instance.
     pub fn new() -> Logger {
         Self { dispatches: vec![] }
     }
 }
 
 impl Logger {
-    /// Add a [Dispatch] to the [Logger].
+    /// Add a [`Dispatch`] to the [`Logger`].
     pub fn dispatch(mut self, dispatch: Dispatch) -> Logger {
         self.dispatches.push(dispatch);
         self
     }
 
-    /// Set up the global logger with the [Logger] instance.
+    /// Set up the global logger with the [`Logger`] instance.
     ///
     /// # Errors
     ///