Struct LoggerBuilder 

pub struct LoggerBuilder { /* private fields */ }

Available on crate feature std only.

Builder for Logger. Construct with Logger::builder.

The builder is not generic over a format. Each call that installs a sink (Self::with_sink, Self::stdout, Self::stderr, Self::writer, or one of the format-specific shortcuts) carries its own format.

Implementations

impl LoggerBuilder

pub fn level(self, level: Level) -> Self

Set the default minimum severity.

pub fn filter(self, filter: Filter) -> Self

Replace the filter wholesale.

pub fn target_level(self, target: impl Into<String>, level: Level) -> Self

Add a per-target filter override. See Filter::with_rule.

pub fn filter_directive(self, directive: &str) -> Self

Parse directive and replace the filter. Silently retains the previous filter on parse error; use Filter::parse up front if you need to surface the error.

pub fn no_timestamps(self) -> Self

Disable timestamp capture. By default the logger records a timestamp on every record using std::time::SystemTime.

pub fn no_context(self) -> Self

Disable thread-local context capture.

pub fn with_default_field<'a, V: Into<Value<'a>>>( self, key: impl Into<String>, value: V, ) -> Self

Attach a field that the logger emits on every record. Useful for service-level identifiers like service_name or version.

pub fn on_error(self, handler: Arc<dyn Fn(&Error) + Send + Sync>) -> Self

Install a callback invoked when a sink returns an error.

pub fn with_sink(self, sink: impl Sink + 'static) -> Self

Install a sink directly. Use this when you have a pre-built sink (typical for crate::sink::FileSink which is fallible to open).

pub fn stdout<F>(self, format: F) -> Self

where F: Format + Send + Sync + 'static,

Install a stdout sink with the given format.

pub fn stderr<F>(self, format: F) -> Self

where F: Format + Send + Sync + 'static,

Install a stderr sink with the given format.

pub fn writer<W, F>(self, writer: W, format: F) -> Self

where W: Write + Send + 'static, F: Format + Send + Sync + 'static,

Install a sink that writes to writer with format.

pub fn build(self) -> Logger

Finish configuration. Panics if no sink has been installed.

Panics

Panics if Self::with_sink, Self::stdout, Self::stderr, Self::writer, or one of the format shortcuts has not been called. Building a logger without a destination is almost certainly a programmer error.

impl LoggerBuilder

pub fn stdout_json(self) -> Self

Available on crate feature json only.

Install a stdout sink with the default JSON format.

pub fn stderr_json(self) -> Self

Available on crate feature json only.

Install a stderr sink with the default JSON format.

impl LoggerBuilder

pub fn stdout_logfmt(self) -> Self

Available on crate feature logfmt only.

Install a stdout sink with the logfmt format.

pub fn stderr_logfmt(self) -> Self

Available on crate feature logfmt only.

Install a stderr sink with the logfmt format.

impl LoggerBuilder

pub fn stdout_human(self) -> Self

Available on crate feature human only.

Install a stdout sink with the human-readable format.

pub fn stderr_human(self) -> Self

Available on crate feature human only.

Install a stderr sink with the human-readable format.