6 releases (3 stable)
1.0.2 | Dec 10, 2022 |
---|---|
1.0.1 | Mar 13, 2021 |
0.2.0 | Jul 2, 2018 |
0.1.1 | Mar 25, 2018 |
0.1.0 | Sep 1, 2017 |
#536 in Debugging
53 downloads per month
Used in 6 crates
19KB
391 lines
slog-try
Convenience macros for logging with an optional slog Logger.
NOTE - See the bottom of this README for another method of using a Logger that doesn't require Option<Logger>
Current Release
Required dependencies
Add slog-try
as a dependency in your Cargo.toml file.
[dependencies]
slog-try = "1"
Project setup
Add use statements for the macros you wish to use:
use slog_try::try_info;
Usage example
Consider HasOptLogger
, a data strcuture with an optionally attachable logger:
#[derive(Default)]
struct HasOptLogger {
logger: Option<Logger>,
}
The macros contained in slog-try
encapsulate the required boilerplate to use this logger without verifying whether the optional field actually contains a logger or not:
let mut opt_logger = HasOptLogger { logger: None };
// Try to log even if no logger exist
try_info!(opt_logger.logger, "You won't see me output. The logger is None."; "opt" => "None");
try_info!(opt_logger.logger, #"imatag", "You won't see me output. The logger is None."; "opt" => "None");
// Setup a `Logger`
let plain = slog_term::PlainSyncDecorator::new(::std::io::stdout());
let logger = Logger::root(slog_term::FullFormat::new(plain)
.build()
.fuse(), o!("surname" => "Lava"));
opt_logger.logger = Some(logger);
// Call again with the new attached logger
try_info!(opt_logger.logger, "You will see me output!"; "opt" => "Some");
try_info!(opt_logger.logger, #"imatag", "You will see me output!"; "opt" => "Some");
Using a Discard Logger
You can use slogs Discard
drain in lieu of the Option
wrapped logger. Like the try_*
macros, in case of a none present logger, the discarding logger is going to drop all incoming messages.
How to initialize a discarding logger
use slog::{Logger, Discard, o};
fn main() {
let logger = Logger::root(Discard, o!());
info!(logger, "nothing happens");
}
Dependencies
~160KB