[−][src]Crate slog_scope

Logging scopes for slog-rs

Logging scopes are convenience functionality for slog-rs to free user from manually passing Logger objects around.

Set of macros is also provided as an alternative to original slog crate macros, for logging directly to Logger of the current logging scope.

Set global logger upfront

Warning: Since slog-scope version 4.0.0, slog-scope defaults to panicking on logging if no scope or global logger was set. Because of it, it is advised to always set a global logger upfront with set_global_logger.

Using `slog-scope` as a part of API is not advised

Part of a slog logging philosophy is ability to freely express logging contexts according to logical structure, rather than callstack structure. By using logging scopes the logging context is tied to code flow again, which is less expressive.

It is generally advised NOT to use slog_scope in libraries. Read more in slog-rs FAQ

#[macro_use(slog_o, slog_info, slog_log, slog_record, slog_record_static, slog_b, slog_kv)]
extern crate slog;
#[macro_use]
extern crate slog_scope;
extern crate slog_term;

use slog::Drain;

fn foo() {
    slog_info!(slog_scope::logger(), "foo");
    info!("foo"); // Same as above, but more ergonomic and a bit faster
                  // since it uses `with_logger`
}

fn main() {
    let plain = slog_term::PlainSyncDecorator::new(std::io::stdout());
    let log = slog::Logger::root(
        slog_term::FullFormat::new(plain)
        .build().fuse(), slog_o!()
    );

    // Make sure to save the guard, see documentation for more information
    let _guard = slog_scope::set_global_logger(log);
    slog_scope::scope(&slog_scope::logger().new(slog_o!("scope" => "1")),
        || foo()
    );
}

Macros

crit	Log a critical level message using current scope logger
debug	Log a debug level message using current scope logger
error	Log a error level message using current scope logger
info	Log a info level message using current scope logger
slog_crit	Log critical level record (alias)
slog_debug	Log debug level record (alias)
slog_error	Log error level record
slog_info	Log info level record (alias)
slog_trace	Log trace level record (alias)
slog_warn	Log warning level record (alias)
trace	Log a trace level message using current scope logger
warn	Log a warning level message using current scope logger

Structs

GlobalLoggerGuard

Guard resetting global logger

Functions