Crate tina::log_mdc

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Expand description

A mapped diagnostic context (MDC) for use with the log crate.

An MDC is a thread local map of strings used to make relevant information from a system available in its log messages. Logging crates such as log4rs will retrieve values from the MDC for output.

For example, a web server may process many requests simultaneously on different threads. Generating an ID for each request and storing it in the MDC makes it easy to partition log messages on a per-request basis.

Examples

Forwarding the contents of the MDC to a new thread:

use std::thread;

let mut mdc = vec![];
log_mdc::iter(|k, v| mdc.push((k.to_owned(), v.to_owned())));

thread::spawn(|| {
    log_mdc::extend(mdc);
});

Structs

  • ExtendGuard
    A guard objects which restores MDC entries when dropped.
  • InsertGuard
    A guard object which restores an MDC entry when dropped.

Functions

  • clear
    Removes all values from the MDC.
  • extend
    Extends the MDC with new entries.
  • extend_scoped
    Extends the MDC with new entries in a scoped fashion.
  • get
    Retrieves a value from the MDC.
  • insert
    Inserts a new entry into the MDC, returning the old value.
  • insert_scoped
    Inserts a new entry into the MDC in a scoped fashion.
  • iter
    Invokes the provided closure for each entry in the MDC.
  • remove
    Removes a value from the MDC.