tracing-core

Changed

• Bump MSRV to 1.65 (#3033)

Fixed

• Do not compare references to pointers to compare pointers (#3236)

Added

• Add index API for Field (#2820)
• allow &[u8] to be recorded as event/span field (#2954)

Changed

• Bump MSRV to 1.63 (#2793)
• Use const thread_locals when possible (#2838)

Fixed

• Fix missed register_callsite error (#2938)
• Do not add valuable/std feature as dependency unless valuable is used (#3002)
• prefix macro calls with ::core to avoid clashing with local macros (#3024)

Documented

• Fix incorrect (incorrectly updated) docs for LevelFilter (#2767)

Thanks to new contributor @maddiemort for contributing to this release!

Documented

• Fix typo in field docs (#2611)
• Remove duplicate wording (#2674)

Changed

• Allow ValueSets of any length (#2508)

This release of tracing-core fixes a bug that caused threads which call dispatcher::get_default before a global default subscriber is set to never see the global default once it is set. In addition, it includes improvements for instrumentation performance in some cases, especially when using a global default dispatcher.

Fixed

• Fixed incorrect thread-local caching of Dispatch::none if dispatcher::get_default is called before dispatcher::set_global_default (#2593)

Changed

• Cloning a Dispatch that points at a global default subscriber no longer requires an Arc reference count increment, improving performance substantially (#2593)
• dispatcher::get_default no longer attempts to access a thread local if the scoped dispatcher is not in use, improving performance when the default dispatcher is global (#2593)
• Added #[inline] annotations called by the event! and span! macros to reduce the size of macro-generated code and improve recording performance (#2555)

Thanks to new contributor @ldm0 for contributing to this release!

This release of tracing-core adds a new on_register_dispatch method to the Subscriber trait to allow the Subscriber to perform initialization after being registered as a Dispatch, and a WeakDispatch type to allow a Subscriber to store its own Dispatch without creating reference count cycles.

Added

• Subscriber::on_register_dispatch method (#2269)
• WeakDispatch type and Dispatch::downgrade() function (#2293)

Thanks to @jswrenn for contributing to this release!

This release of tracing-core adds PartialEq and Eq implementations for metadata types, and improves error messages when setting the global default subscriber fails.

Added

• PartialEq and Eq implementations for Metadata (#2229)
• PartialEq and Eq implementations for FieldSet (#2229)

Fixed

• Fixed unhelpful fmt::Debug output for dispatcher::SetGlobalDefaultError (#2250)
• Fixed compilation with -Z minimal-versions (#2246)

Thanks to @jswrenn and @CAD97 for contributing to this release!

This release of tracing-core adds new Value implementations, including one for String, to allow recording &String as a value without having to call as_str() or similar, and for 128-bit integers (i128 and u128). In addition, it adds new methods and trait implementations for Subscribers.

Added

• Value implementation for String (#2164)
• Value implementation for u128 and i28 (#2166)
• downcast_ref and is methods for dyn Subscriber + Sync, dyn Subscriber + Send, and dyn Subscriber + Send + Sync (#2160)
• Subscriber::event_enabled method to enable filtering based on Event field values (#2008)
• Subscriber implementation for Box<S: Subscriber + ?Sized> and Arc<S: Subscriber + ?Sized> (#2161)

Thanks to @jswrenn and @CAD97 for contributing to this release!

This release of tracing-core introduces a new DefaultCallsite type, which can be used by instrumentation crates rather than implementing their own callsite types. Using DefaultCallsite may offer reduced overhead from callsite registration.

Added

• DefaultCallsite, a pre-written Callsite implementation for use in instrumentation crates (#2083)
• ValueSet::len and Record::len methods returning the number of fields in a ValueSet or Record (#2152)

Changed

• Replaced lazy_static dependency with once_cell (#2147)

Documented

• Added documentation to the callsite module (#2088, #2149)

Thanks to new contributors @jamesmunns and @james7132 for contributing to this release!

This release adds a Value implementation for Box<T: Value> to allow recording boxed values more conveniently. In particular, this should improve the ergonomics of the implementations for dyn std::error::Error trait objects, including those added in v0.1.25.

Added

• Value implementation for Box<T> where T: Value (#2071)

Fixed

• Broken documentation links (#2068)

Thanks to new contributor @ben0x539 for contributing to this release!

This release adds additional Value implementations for std::error::Error trait objects with auto trait bounds (Send and Sync), as Rust will not auto-coerce trait objects. Additionally, it fixes a bug when setting scoped dispatchers that was introduced in the previous release (v0.1.24).

Added

• Value implementations for dyn Error + Send + 'static, dyn Error + Send + Sync + 'static, dyn Error + Sync + 'static (#2066)

Fixed

• Failure to use the global default dispatcher if a thread has set a scoped default prior to setting the global default, and unset the scoped default after setting the global default (#2065)

Thanks to @lilyball for contributing to this release!

This release fixes a bug where setting NoSubscriber as the local default would not disable the global default subscriber locally.

Fixed

• Setting NoSubscriber as the local default now correctly disables the global default subscriber (#2001)
• Fixed compilation warnings with the "std" feature disabled (#2022)

Changed

• Removed unnecessary use of write! and format_args! macros (#1988)

Changed

• Removed #[inline] attributes from some Dispatch methods whose callers are now inlined (#1974)
• Bumped minimum supported Rust version (MSRV) to Rust 1.49.0 (#1913)

This release adds experimental support for recording structured field values using the valuable crate. See this blog post for details on valuable.

Note that valuable support currently requires --cfg tracing_unstable. See the documentation for details.

Added

• field: Experimental support for recording field values using the valuable crate (#1608, #1888, #1887)
• field: Added ValueSet::record method (#1823)
• subscriber: Default impl for NoSubscriber (#1785)
• metadata: New Kind::HINT to support the enabled! macro in tracing (#1883, #1891)

Fixed

• Fixed a number of documentation issues (#1665, #1692, #1737)

Thanks to @xd009642, @Skepfyr, @guswynn, @Folyd, and @mbergkvist for contributing to this release!

This release adds support for recording Option<T> where T: Value as typed tracing field values.

Added

• field: Value impl for Option<T> where T: Value (#1585)

Fixed

• Fixed deprecation warnings when building with default-features disabled (#1603, #1606)
• Documentation fixes and improvements (#1595, #1601)

Thanks to @brianburgers, @DCjanus, and @matklad for contributing to this release!

This release adds support for f64 as one of the tracing-core primitive field values, allowing floating-point values to be recorded as typed values rather than with fmt::Debug. Additionally, it adds NoSubscriber, a Subscriber implementation that does nothing.

Added

• subscriber: NoSubscriber, a no-op Subscriber implementation (#1549)
• field: Added Visit::record_f64 and support for recording floating-point values (#1507)

Thanks to new contributors @jsgf and @maxburke for contributing to this release!

Added

• Level::as_str (#1413)
• Hash implementation for Level and LevelFilter (#1456)
• Value implementation for &mut T where T: Value (#1385)
• Multiple documentation fixes and improvements (#1435, #1446)

Thanks to @Folyd, @teozkr, and @dvdplm for contributing to this release!

Added

• Subscriber impl for Box<dyn Subscriber + Send + Sync + 'static> (#1358)
• Subscriber impl for Arc<dyn Subscriber + Send + Sync + 'static> (#1374)
• Symmetric From impls for existing Into impls on Current and Option<Id> (#1335)
• Attributes::fields accessor that returns the set of fields defined on a span's Attributes (#1331)

Thanks to @Folyd for contributing to this release!

Fixed

• Incorrect inlining of Event::dispatch and Event::child_of, which could result in dispatcher::get_default being inlined at the callsite (#994)

Added

• Copy implementations for Level and LevelFilter (#992)

Thanks to new contributors @jyn514 and @TaKO8Ki for contributing to this release!

Fixed

• Added a conversion from Option<Level> to LevelFilter. This resolves a previously unreported regression where Option<Level> was no longer a valid LevelFilter. (#966)

Fixed

• When combining Interest from multiple subscribers, if the interests differ, the current subscriber is now always asked if a callsite should be enabled (#927)

Added

• Internal API changes to support optimizations in the tracing crate (#943)
• docs: Multiple fixes and improvements (#913, #941)

Fixed

• Incorrect calculation of global max level filter which could result in fast filtering paths not being taken (#908)

Fixed

• Missing fmt::Display impl for field::DisplayValue causing a compilation failure when the "log" feature is enabled (#887)

Thanks to @d-e-s-o for contributing to this release!

Added

• LevelFilter type and LevelFilter::current() for returning the highest level that any subscriber will enable (#853)
• Subscriber::max_level_hint optional trait method, for setting the value returned by LevelFilter::current() (#853)

Fixed

• docs: Removed outdated reference to a Tokio API that no longer exists (#857)

Thanks to new contributor @dignati for contributing to this release!

Changed

• Replaced use of inner_local_macros with $crate:: (#729)

Added

• must_use warning to guards returned by dispatcher::set_default (#686)
• fmt::Debug impl to dyn Values (#696)
• Functions to convert between span::Id and NonZeroU64 (#770)
• More obvious warnings in documentation (#769)

Fixed

• Compiler error when tracing-core/std feature is enabled but tracing/std is not (#760)
• Clippy warning on vtable address comparison in callsite::Identifier (#749)
• Documentation formatting issues (#715, #771)

Thanks to @bkchr, @majecty, @taiki-e, @nagisa, and @nvzqz for contributing to this release!

Added

• field::Empty type for declaring empty fields whose values will be recorded later (#548)
• field::Value implementations for Wrapping and NonZero* numbers (#538)

Fixed

• Broken and unresolvable links in RustDoc (#595)

Thanks to @oli-cosmian for contributing to this release!

Added

• API docs now show what feature flags are required to enable each item (#523)

Fixed

• A panic when the current default subscriber subscriber calls dispatcher::with_default as it is being dropped (#522)
• Incorrect documentation for Subscriber::drop_span (#524)

Added

• Default impl for Dispatch (#411)

Fixed

• Removed duplicate lazy_static dependencies (#424)
• Fixed no-std dependencies being enabled even when std feature flag is set (#424)
• Broken link to Metadata in Event docs (#461)

Added

• Added dispatcher::set_default API which returns a drop guard (#388)

Fixed

• Added missing Value impl for u8 (#392)
• Broken links in docs.

Added

• Internal APIs to support performance optimizations (#326)

Fixed

• Clarified wording in field::display documentation (#340)

Added

• std::error::Error as a new primitive Value type (#277)
• Event::new and Event::new_child_of to manually construct Events (#281)

Added

• Support for no-std + liballoc (#256)

Fixed

• Broken links in RustDoc (#259)

Added

• std::fmt::Display implementation for Level (#194)
• std::str::FromStr implementation for Level (#195)

Deprecated

• Subscriber::drop_span in favor of new Subscriber::try_close (#168)

Added

• Into<Option<&Id>>, Into<Option<Id>>, and Into<Option<&'static Metadata<'static>>> impls for span::Current (#170)
• Subscriber::try_close method (#153)
• Improved documentation for dispatcher (#171)

Added

• Subscriber::current_span API to return the current span (#148).
• span::Current type, representing the Subscriber's view of the current span (#148).

Fixed

• Typos and broken links in documentation (#123, #124, #128, #154)

• Initial release