Crate tracing_subscriber
source · [−]Expand description
Utilities for implementing and composing tracing
subscribers.
tracing
is a framework for instrumenting Rust programs to collect
scoped, structured, and async-aware diagnostics. The Subscriber
trait
represents the functionality necessary to collect this trace data. This
crate contains tools for composing subscribers out of smaller units of
behaviour, and batteries-included implementations of common subscriber
functionality.
tracing-subscriber
is intended for use by both Subscriber
authors and
application authors using tracing
to instrument their applications.
Compiler support: requires rustc
1.42+
Included Subscribers
The following Subscriber
s are provided for application authors:
fmt
- Formats and logs tracing data (requires thefmt
feature flag)
Feature Flags
env-filter
: Enables theEnvFilter
type, which implements filtering similar to theenv_logger
crate. Enabled by default.fmt
: Enables thefmt
module, which provides a subscriber implementation for printing formatted representations of trace events. Enabled by default.ansi
: Enablesfmt
support for ANSI terminal colors. Enabled by default.registry
: enables theregistry
module. Enabled by default.json
: Enablesfmt
support for JSON output. In JSON output, the ANSI feature does nothing.
Optional Dependencies
tracing-log
: Enables better formatting for events emitted bylog
macros in thefmt
subscriber. On by default.chrono
: Enables human-readable time formatting in thefmt
subscriber. Enabled by default.smallvec
: Causes theEnvFilter
type to use thesmallvec
crate (rather thanVec
) as a performance optimization. Enabled by default.parking_lot
: Use theparking_lot
crate’sRwLock
implementation rather than the Rust standard library’s implementation.
Supported Rust Versions
Tracing is built against the latest stable release. The minimum supported version is 1.42. The current Tracing version is not guaranteed to build on Rust versions earlier than the minimum supported version.
Tracing follows the same compiler support policies as the rest of the Tokio project. The current stable Rust compiler and the three most recent minor versions before it will always be supported. For example, if the current stable compiler version is 1.45, the minimum supported version will not be increased past 1.42, three minor versions prior. Increasing the minimum supported compiler version is not considered a semver breaking change as long as doing so complies with this policy.
Re-exports
Modules
Utilities for working with fields and field visitors.
A Subscriber
for formatting and logging tracing
data.
A composable abstraction for building Subscriber
s.
The tracing-subscriber
prelude.
Wrapper for a Layer
to allow it to be dynamically reloaded.
Extension traits and other utilities to make working with subscribers more ergonomic.
Structs
Tracks the currently executing span on a per-thread basis.
A shared, reusable store for spans.