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Levels, context and macros

Everything is written through the static my_logger::LOGGER. It needs no initialization and is used from any thread.

Levels

Method Level
write_info Info
write_warning Warning
write_error Error
write_fatal_error FatalError
write_debug Debug

Each of them takes the process, the message and the context:

use my_logger::LogEventCtx;

my_logger::LOGGER.write_error(
    "process_name",
    format!("Can not execute order {}", order_id),
    LogEventCtx::new().add("orderId", order_id.to_string()),
);
  • The process is where it happened: a &'static str or a String.
  • The message is a &str or a String.
  • The context is the keys and values of the record: LogEventCtx::new() when there are none.

write_fatal_debug is deprecated: write_debug writes the same.

Context

let ctx = LogEventCtx::new()
    .add("orderId", "15")
    .add_object("result", &result);
Method
add(key, value) The value is a &str or a String.
add_object(key, &value) The value is anything with Debug, written as {:?}.
LogEventCtx::from_object(key, &value) A context of one add_object.

A key is a &'static str or a String. A key added twice keeps the last value. A HashMap<String, String> and a BTreeMap<String, String> turn into a context with .into().

Macros

The same in one line - the process, the message, then "key" = value pairs:

my_logger::write_log_info!("process_name", "message", "orderId" = order_id, "result" = result);
Macro Level
write_log_info! Info
write_log_warning! Warning
write_log_err! Error
write_log_fatal! FatalError
write_log_debug! Debug
  • A value is anything with Debug and is written as {:?}, so a string comes with its quotes.
  • With no pairs the comma after the message stays: write_log_info!("process_name", "message",);.
  • The macros name the crate as my_logger. When it comes through another crate, bring it into scope under that name: use service_sdk::my_logger;.

Logger of rust-extensions

MyLogger implements rust_extensions::Logger, so my_logger::LOGGER.clone() goes wherever an Arc<dyn Logger + Send + Sync + 'static> is asked for - MyTimer, BackgroundExecutor and the like.