Struct LoggerBuilder 

pub struct LoggerBuilder { /* private fields */ }

Constructs an nice-log logger.

Implementations

impl LoggerBuilder

pub fn new(max_log_level: LevelFilter) -> Self

Create a builder for a logger. The logger can be installed using the build_global() function.

Examples found in repository

examples/filtered.rs (line 4)

fn main() {
    nice_log::LoggerBuilder::new(LevelFilter::Trace)
        // Filtering only works with exact matches, so the log messages from
        // `some_module::some_sub_module` will still show up
        .filter_module("filtered::some_module")
        .build_global()
        .expect("A logger has already been set up");

    some_module::log();
    some_module::some_sub_module::log();
}

examples/basic.rs (line 6)

fn main() {
    // The log output is determined by the `NICE_LOG` environment variable as dedicated by the rules
    // outlined in the repository's readme
    nice_log::LoggerBuilder::new(LevelFilter::Trace)
        .build_global()
        // In this example something would be have gone very wrong if we cannot set up the logger.
        // If there however is a possibility that the logger is configured multiple times then this
        // error should be handled appropriately.
        .expect("A logger has already been set up");

    // When changing some of the level filter above some of these messages may no longer be printed
    log::error!("This is an error");
    log::warn!("This is a warning");
    log::info!("This is a regular log message");
    log::debug!("This is a debug message, usually only made visible during debug builds");
    log::trace!("This is a trace message, usually hidden unless explicitly opted into");

    // Debug and trace messages contain the module path
    some_module::log_from_module();
}

pub fn build_global(self) -> Result<(), SetLoggerError>

Install the configured logger as the global logger. The global logger can only be set once.

Examples found in repository

examples/filtered.rs (line 8)

fn main() {
    nice_log::LoggerBuilder::new(LevelFilter::Trace)
        // Filtering only works with exact matches, so the log messages from
        // `some_module::some_sub_module` will still show up
        .filter_module("filtered::some_module")
        .build_global()
        .expect("A logger has already been set up");

    some_module::log();
    some_module::some_sub_module::log();
}

examples/basic.rs (line 7)

fn main() {
    // The log output is determined by the `NICE_LOG` environment variable as dedicated by the rules
    // outlined in the repository's readme
    nice_log::LoggerBuilder::new(LevelFilter::Trace)
        .build_global()
        // In this example something would be have gone very wrong if we cannot set up the logger.
        // If there however is a possibility that the logger is configured multiple times then this
        // error should be handled appropriately.
        .expect("A logger has already been set up");

    // When changing some of the level filter above some of these messages may no longer be printed
    log::error!("This is an error");
    log::warn!("This is a warning");
    log::info!("This is a regular log message");
    log::debug!("This is a debug message, usually only made visible during debug builds");
    log::trace!("This is a trace message, usually hidden unless explicitly opted into");

    // Debug and trace messages contain the module path
    some_module::log_from_module();
}

pub fn always_show_module_path(self) -> Self

Always show the module path. Normally this is only shown for the messages on the Debug level or on higher verbosity levels. Useful for debugging.

pub fn filter_crate(self, crate_name: impl Into<String>) -> Self

Filter out log messages produced by the given crate.

pub fn filter_module(self, crate_name: impl Into<String>) -> Self

Filter out log messages produced by the given module. Module names are matched exactly and case sensitively. Filtering based on a module prefix is currently not supported.

Examples found in repository

examples/filtered.rs (line 7)

fn main() {
    nice_log::LoggerBuilder::new(LevelFilter::Trace)
        // Filtering only works with exact matches, so the log messages from
        // `some_module::some_sub_module` will still show up
        .filter_module("filtered::some_module")
        .build_global()
        .expect("A logger has already been set up");

    some_module::log();
    some_module::some_sub_module::log();
}

pub fn with_output_target( self, target: OutputTarget, ) -> Result<Self, SetTargetError>

Explicitly set the output target for the logger. This is normally set using the NICE_LOG environment variable. Returns an error if the target could not be set.

Trait Implementations

impl Debug for LoggerBuilder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<SetTargetError> for LoggerBuilder

fn from(value: SetTargetError) -> Self

Converts to this type from the input type.