Crate tracing_core

Core primitives for tracing.

tracing is a framework for instrumenting Rust programs to collect structured, event-based diagnostic information. This crate defines the core primitives of tracing.

This crate provides:

• Span identifies a span within the execution of a program.

• Event represents a single event within a trace.

• Subscriber, the trait implemented to collect trace data.

• Metadata and Callsite provide information describing Spans.

• Field, FieldSet, Value, and ValueSet represent the structured data attached to a Span.

• Dispatch allows span events to be dispatched to Subscribers.

In addition, it defines the global callsite registry and per-thread current dispatcher which other components of the tracing system rely on.

Application authors will typically not use this crate directly. Instead, they will use the tracing crate, which provides a much more fully-featured API. However, this crate's API will change very infrequently, so it may be used when dependencies must be very stable.

The tokio-rs/tracing repository contains less stable crates designed to be used with the tracing ecosystem. It includes a collection of Subscriber implementations, as well as utility and adapter crates.

Re-exports

pub use self::callsite::Callsite;

pub use self::dispatcher::Dispatch;

pub use self::event::Event;

pub use self::field::Field;

pub use self::metadata::Kind;

pub use self::metadata::Level;

pub use self::metadata::Metadata;

pub use self::subscriber::Interest;

pub use self::subscriber::Subscriber;

Modules

callsite	Callsites represent the source locations from which spans or events originate.
dispatcher	Dispatches trace events to Subscribers.c
event	Events represent single points in time during the execution of a program.
field	Span and Event key-value data.
metadata	Metadata describing trace data.
span	Spans represent periods of time in the execution of a program.
subscriber	Subscribers collect and record trace data.

Macros

identify_callsite	Statically constructs an Identifier for the provided Callsite.
metadata	Statically constructs new span metadata.