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Diffstat (limited to 'vendor/tracing-subscriber/src/fmt/fmt_layer.rs')
| -rw-r--r-- | vendor/tracing-subscriber/src/fmt/fmt_layer.rs | 1472 |
1 files changed, 1472 insertions, 0 deletions
diff --git a/vendor/tracing-subscriber/src/fmt/fmt_layer.rs b/vendor/tracing-subscriber/src/fmt/fmt_layer.rs new file mode 100644 index 000000000..6e4e2ac0b --- /dev/null +++ b/vendor/tracing-subscriber/src/fmt/fmt_layer.rs @@ -0,0 +1,1472 @@ +use crate::{ + field::RecordFields, + fmt::{format, FormatEvent, FormatFields, MakeWriter, TestWriter}, + layer::{self, Context}, + registry::{self, LookupSpan, SpanRef}, +}; +use format::{FmtSpan, TimingDisplay}; +use std::{any::TypeId, cell::RefCell, fmt, io, marker::PhantomData, ops::Deref, time::Instant}; +use tracing_core::{ + field, + span::{Attributes, Current, Id, Record}, + Event, Metadata, Subscriber, +}; + +/// A [`Layer`] that logs formatted representations of `tracing` events. +/// +/// ## Examples +/// +/// Constructing a layer with the default configuration: +/// +/// ```rust +/// use tracing_subscriber::{fmt, Registry}; +/// use tracing_subscriber::prelude::*; +/// +/// let subscriber = Registry::default() +/// .with(fmt::Layer::default()); +/// +/// tracing::subscriber::set_global_default(subscriber).unwrap(); +/// ``` +/// +/// Overriding the layer's behavior: +/// +/// ```rust +/// use tracing_subscriber::{fmt, Registry}; +/// use tracing_subscriber::prelude::*; +/// +/// let fmt_layer = fmt::layer() +/// .with_target(false) // don't include event targets when logging +/// .with_level(false); // don't include event levels when logging +/// +/// let subscriber = Registry::default().with(fmt_layer); +/// # tracing::subscriber::set_global_default(subscriber).unwrap(); +/// ``` +/// +/// Setting a custom event formatter: +/// +/// ```rust +/// use tracing_subscriber::fmt::{self, format, time}; +/// use tracing_subscriber::prelude::*; +/// +/// let fmt = format().with_timer(time::Uptime::default()); +/// let fmt_layer = fmt::layer() +/// .event_format(fmt) +/// .with_target(false); +/// # let subscriber = fmt_layer.with_subscriber(tracing_subscriber::registry::Registry::default()); +/// # tracing::subscriber::set_global_default(subscriber).unwrap(); +/// ``` +/// +/// [`Layer`]: super::layer::Layer +#[cfg_attr(docsrs, doc(cfg(all(feature = "fmt", feature = "std"))))] +#[derive(Debug)] +pub struct Layer< + S, + N = format::DefaultFields, + E = format::Format<format::Full>, + W = fn() -> io::Stdout, +> { + make_writer: W, + fmt_fields: N, + fmt_event: E, + fmt_span: format::FmtSpanConfig, + is_ansi: bool, + log_internal_errors: bool, + _inner: PhantomData<fn(S)>, +} + +impl<S> Layer<S> { + /// Returns a new [`Layer`][self::Layer] with the default configuration. + pub fn new() -> Self { + Self::default() + } +} + +// This needs to be a seperate impl block because they place different bounds on the type parameters. +impl<S, N, E, W> Layer<S, N, E, W> +where + S: Subscriber + for<'a> LookupSpan<'a>, + N: for<'writer> FormatFields<'writer> + 'static, + W: for<'writer> MakeWriter<'writer> + 'static, +{ + /// Sets the [event formatter][`FormatEvent`] that the layer being built will + /// use to format events. + /// + /// The event formatter may be any type implementing the [`FormatEvent`] + /// trait, which is implemented for all functions taking a [`FmtContext`], a + /// [`Writer`], and an [`Event`]. + /// + /// # Examples + /// + /// Setting a type implementing [`FormatEvent`] as the formatter: + /// ```rust + /// use tracing_subscriber::fmt::{self, format}; + /// + /// let layer = fmt::layer() + /// .event_format(format().compact()); + /// # // this is necessary for type inference. + /// # use tracing_subscriber::Layer as _; + /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default()); + /// ``` + /// [`FormatEvent`]: format::FormatEvent + /// [`Event`]: tracing::Event + /// [`Writer`]: format::Writer + pub fn event_format<E2>(self, e: E2) -> Layer<S, N, E2, W> + where + E2: FormatEvent<S, N> + 'static, + { + Layer { + fmt_fields: self.fmt_fields, + fmt_event: e, + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } + + /// Updates the event formatter by applying a function to the existing event formatter. + /// + /// This sets the event formatter that the layer being built will use to record fields. + /// + /// # Examples + /// + /// Updating an event formatter: + /// + /// ```rust + /// let layer = tracing_subscriber::fmt::layer() + /// .map_event_format(|e| e.compact()); + /// # // this is necessary for type inference. + /// # use tracing_subscriber::Layer as _; + /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default()); + /// ``` + pub fn map_event_format<E2>(self, f: impl FnOnce(E) -> E2) -> Layer<S, N, E2, W> + where + E2: FormatEvent<S, N> + 'static, + { + Layer { + fmt_fields: self.fmt_fields, + fmt_event: f(self.fmt_event), + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } +} + +// This needs to be a seperate impl block because they place different bounds on the type parameters. +impl<S, N, E, W> Layer<S, N, E, W> { + /// Sets the [`MakeWriter`] that the layer being built will use to write events. + /// + /// # Examples + /// + /// Using `stderr` rather than `stdout`: + /// + /// ```rust + /// use std::io; + /// use tracing_subscriber::fmt; + /// + /// let layer = fmt::layer() + /// .with_writer(io::stderr); + /// # // this is necessary for type inference. + /// # use tracing_subscriber::Layer as _; + /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default()); + /// ``` + pub fn with_writer<W2>(self, make_writer: W2) -> Layer<S, N, E, W2> + where + W2: for<'writer> MakeWriter<'writer> + 'static, + { + Layer { + fmt_fields: self.fmt_fields, + fmt_event: self.fmt_event, + fmt_span: self.fmt_span, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + make_writer, + _inner: self._inner, + } + } + + /// Borrows the [writer] for this [`Layer`]. + /// + /// [writer]: MakeWriter + pub fn writer(&self) -> &W { + &self.make_writer + } + + /// Mutably borrows the [writer] for this [`Layer`]. + /// + /// This method is primarily expected to be used with the + /// [`reload::Handle::modify`](crate::reload::Handle::modify) method. + /// + /// # Examples + /// + /// ``` + /// # use tracing::info; + /// # use tracing_subscriber::{fmt,reload,Registry,prelude::*}; + /// # fn non_blocking<T: std::io::Write>(writer: T) -> (fn() -> std::io::Stdout) { + /// # std::io::stdout + /// # } + /// # fn main() { + /// let layer = fmt::layer().with_writer(non_blocking(std::io::stderr())); + /// let (layer, reload_handle) = reload::Layer::new(layer); + /// # + /// # // specifying the Registry type is required + /// # let _: &reload::Handle<fmt::Layer<Registry, _, _, _>, Registry> = &reload_handle; + /// # + /// info!("This will be logged to stderr"); + /// reload_handle.modify(|layer| *layer.writer_mut() = non_blocking(std::io::stdout())); + /// info!("This will be logged to stdout"); + /// # } + /// ``` + /// + /// [writer]: MakeWriter + pub fn writer_mut(&mut self) -> &mut W { + &mut self.make_writer + } + + /// Sets whether this layer should use ANSI terminal formatting + /// escape codes (such as colors). + /// + /// This method is primarily expected to be used with the + /// [`reload::Handle::modify`](crate::reload::Handle::modify) method when changing + /// the writer. + #[cfg(feature = "ansi")] + #[cfg_attr(docsrs, doc(cfg(feature = "ansi")))] + pub fn set_ansi(&mut self, ansi: bool) { + self.is_ansi = ansi; + } + + /// Configures the layer to support [`libtest`'s output capturing][capturing] when used in + /// unit tests. + /// + /// See [`TestWriter`] for additional details. + /// + /// # Examples + /// + /// Using [`TestWriter`] to let `cargo test` capture test output: + /// + /// ```rust + /// use std::io; + /// use tracing_subscriber::fmt; + /// + /// let layer = fmt::layer() + /// .with_test_writer(); + /// # // this is necessary for type inference. + /// # use tracing_subscriber::Layer as _; + /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default()); + /// ``` + /// [capturing]: + /// https://doc.rust-lang.org/book/ch11-02-running-tests.html#showing-function-output + /// [`TestWriter`]: super::writer::TestWriter + pub fn with_test_writer(self) -> Layer<S, N, E, TestWriter> { + Layer { + fmt_fields: self.fmt_fields, + fmt_event: self.fmt_event, + fmt_span: self.fmt_span, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + make_writer: TestWriter::default(), + _inner: self._inner, + } + } + + /// Enable ANSI terminal colors for formatted output. + #[cfg(feature = "ansi")] + #[cfg_attr(docsrs, doc(cfg(feature = "ansi")))] + pub fn with_ansi(self, ansi: bool) -> Self { + Self { + is_ansi: ansi, + ..self + } + } + + /// Sets whether to write errors from [`FormatEvent`] to the writer. + /// Defaults to true. + /// + /// By default, `fmt::Layer` will write any `FormatEvent`-internal errors to + /// the writer. These errors are unlikely and will only occur if there is a + /// bug in the `FormatEvent` implementation or its dependencies. + /// + /// If writing to the writer fails, the error message is printed to stderr + /// as a fallback. + /// + /// [`FormatEvent`]: crate::fmt::FormatEvent + pub fn log_internal_errors(self, log_internal_errors: bool) -> Self { + Self { + log_internal_errors, + ..self + } + } + + /// Updates the [`MakeWriter`] by applying a function to the existing [`MakeWriter`]. + /// + /// This sets the [`MakeWriter`] that the layer being built will use to write events. + /// + /// # Examples + /// + /// Redirect output to stderr if level is <= WARN: + /// + /// ```rust + /// use tracing::Level; + /// use tracing_subscriber::fmt::{self, writer::MakeWriterExt}; + /// + /// let stderr = std::io::stderr.with_max_level(Level::WARN); + /// let layer = fmt::layer() + /// .map_writer(move |w| stderr.or_else(w)); + /// # // this is necessary for type inference. + /// # use tracing_subscriber::Layer as _; + /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default()); + /// ``` + pub fn map_writer<W2>(self, f: impl FnOnce(W) -> W2) -> Layer<S, N, E, W2> + where + W2: for<'writer> MakeWriter<'writer> + 'static, + { + Layer { + fmt_fields: self.fmt_fields, + fmt_event: self.fmt_event, + fmt_span: self.fmt_span, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + make_writer: f(self.make_writer), + _inner: self._inner, + } + } +} + +impl<S, N, L, T, W> Layer<S, N, format::Format<L, T>, W> +where + N: for<'writer> FormatFields<'writer> + 'static, +{ + /// Use the given [`timer`] for span and event timestamps. + /// + /// See the [`time` module] for the provided timer implementations. + /// + /// Note that using the `"time`"" feature flag enables the + /// additional time formatters [`UtcTime`] and [`LocalTime`], which use the + /// [`time` crate] to provide more sophisticated timestamp formatting + /// options. + /// + /// [`timer`]: super::time::FormatTime + /// [`time` module]: mod@super::time + /// [`UtcTime`]: super::time::UtcTime + /// [`LocalTime`]: super::time::LocalTime + /// [`time` crate]: https://docs.rs/time/0.3 + pub fn with_timer<T2>(self, timer: T2) -> Layer<S, N, format::Format<L, T2>, W> { + Layer { + fmt_event: self.fmt_event.with_timer(timer), + fmt_fields: self.fmt_fields, + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } + + /// Do not emit timestamps with spans and event. + pub fn without_time(self) -> Layer<S, N, format::Format<L, ()>, W> { + Layer { + fmt_event: self.fmt_event.without_time(), + fmt_fields: self.fmt_fields, + fmt_span: self.fmt_span.without_time(), + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } + + /// Configures how synthesized events are emitted at points in the [span + /// lifecycle][lifecycle]. + /// + /// The following options are available: + /// + /// - `FmtSpan::NONE`: No events will be synthesized when spans are + /// created, entered, exited, or closed. Data from spans will still be + /// included as the context for formatted events. This is the default. + /// - `FmtSpan::NEW`: An event will be synthesized when spans are created. + /// - `FmtSpan::ENTER`: An event will be synthesized when spans are entered. + /// - `FmtSpan::EXIT`: An event will be synthesized when spans are exited. + /// - `FmtSpan::CLOSE`: An event will be synthesized when a span closes. If + /// [timestamps are enabled][time] for this formatter, the generated + /// event will contain fields with the span's _busy time_ (the total + /// time for which it was entered) and _idle time_ (the total time that + /// the span existed but was not entered). + /// - `FmtSpan::ACTIVE`: Events will be synthesized when spans are entered + /// or exited. + /// - `FmtSpan::FULL`: Events will be synthesized whenever a span is + /// created, entered, exited, or closed. If timestamps are enabled, the + /// close event will contain the span's busy and idle time, as + /// described above. + /// + /// The options can be enabled in any combination. For instance, the following + /// will synthesize events whenever spans are created and closed: + /// + /// ```rust + /// use tracing_subscriber::fmt; + /// use tracing_subscriber::fmt::format::FmtSpan; + /// + /// let subscriber = fmt() + /// .with_span_events(FmtSpan::NEW | FmtSpan::CLOSE) + /// .finish(); + /// ``` + /// + /// Note that the generated events will only be part of the log output by + /// this formatter; they will not be recorded by other `Subscriber`s or by + /// `Layer`s added to this subscriber. + /// + /// [lifecycle]: https://docs.rs/tracing/latest/tracing/span/index.html#the-span-lifecycle + /// [time]: Layer::without_time() + pub fn with_span_events(self, kind: FmtSpan) -> Self { + Layer { + fmt_span: self.fmt_span.with_kind(kind), + ..self + } + } + + /// Sets whether or not an event's target is displayed. + pub fn with_target(self, display_target: bool) -> Layer<S, N, format::Format<L, T>, W> { + Layer { + fmt_event: self.fmt_event.with_target(display_target), + ..self + } + } + /// Sets whether or not an event's [source code file path][file] is + /// displayed. + /// + /// [file]: tracing_core::Metadata::file + pub fn with_file(self, display_filename: bool) -> Layer<S, N, format::Format<L, T>, W> { + Layer { + fmt_event: self.fmt_event.with_file(display_filename), + ..self + } + } + + /// Sets whether or not an event's [source code line number][line] is + /// displayed. + /// + /// [line]: tracing_core::Metadata::line + pub fn with_line_number( + self, + display_line_number: bool, + ) -> Layer<S, N, format::Format<L, T>, W> { + Layer { + fmt_event: self.fmt_event.with_line_number(display_line_number), + ..self + } + } + + /// Sets whether or not an event's level is displayed. + pub fn with_level(self, display_level: bool) -> Layer<S, N, format::Format<L, T>, W> { + Layer { + fmt_event: self.fmt_event.with_level(display_level), + ..self + } + } + + /// Sets whether or not the [thread ID] of the current thread is displayed + /// when formatting events. + /// + /// [thread ID]: std::thread::ThreadId + pub fn with_thread_ids(self, display_thread_ids: bool) -> Layer<S, N, format::Format<L, T>, W> { + Layer { + fmt_event: self.fmt_event.with_thread_ids(display_thread_ids), + ..self + } + } + + /// Sets whether or not the [name] of the current thread is displayed + /// when formatting events. + /// + /// [name]: std::thread#naming-threads + pub fn with_thread_names( + self, + display_thread_names: bool, + ) -> Layer<S, N, format::Format<L, T>, W> { + Layer { + fmt_event: self.fmt_event.with_thread_names(display_thread_names), + ..self + } + } + + /// Sets the layer being built to use a [less verbose formatter][super::format::Compact]. + pub fn compact(self) -> Layer<S, N, format::Format<format::Compact, T>, W> + where + N: for<'writer> FormatFields<'writer> + 'static, + { + Layer { + fmt_event: self.fmt_event.compact(), + fmt_fields: self.fmt_fields, + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } + + /// Sets the layer being built to use an [excessively pretty, human-readable formatter](crate::fmt::format::Pretty). + #[cfg(feature = "ansi")] + #[cfg_attr(docsrs, doc(cfg(feature = "ansi")))] + pub fn pretty(self) -> Layer<S, format::Pretty, format::Format<format::Pretty, T>, W> { + Layer { + fmt_event: self.fmt_event.pretty(), + fmt_fields: format::Pretty::default(), + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } + + /// Sets the layer being built to use a [JSON formatter][super::format::Json]. + /// + /// The full format includes fields from all entered spans. + /// + /// # Example Output + /// + /// ```ignore,json + /// {"timestamp":"Feb 20 11:28:15.096","level":"INFO","target":"mycrate","fields":{"message":"some message", "key": "value"}} + /// ``` + /// + /// # Options + /// + /// - [`Layer::flatten_event`] can be used to enable flattening event fields into the root + /// object. + /// + /// [`Layer::flatten_event`]: Layer::flatten_event() + #[cfg(feature = "json")] + #[cfg_attr(docsrs, doc(cfg(feature = "json")))] + pub fn json(self) -> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> { + Layer { + fmt_event: self.fmt_event.json(), + fmt_fields: format::JsonFields::new(), + fmt_span: self.fmt_span, + make_writer: self.make_writer, + // always disable ANSI escapes in JSON mode! + is_ansi: false, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } +} + +#[cfg(feature = "json")] +#[cfg_attr(docsrs, doc(cfg(feature = "json")))] +impl<S, T, W> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> { + /// Sets the JSON layer being built to flatten event metadata. + /// + /// See [`format::Json`][super::format::Json] + pub fn flatten_event( + self, + flatten_event: bool, + ) -> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> { + Layer { + fmt_event: self.fmt_event.flatten_event(flatten_event), + fmt_fields: format::JsonFields::new(), + ..self + } + } + + /// Sets whether or not the formatter will include the current span in + /// formatted events. + /// + /// See [`format::Json`][super::format::Json] + pub fn with_current_span( + self, + display_current_span: bool, + ) -> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> { + Layer { + fmt_event: self.fmt_event.with_current_span(display_current_span), + fmt_fields: format::JsonFields::new(), + ..self + } + } + + /// Sets whether or not the formatter will include a list (from root to leaf) + /// of all currently entered spans in formatted events. + /// + /// See [`format::Json`][super::format::Json] + pub fn with_span_list( + self, + display_span_list: bool, + ) -> Layer<S, format::JsonFields, format::Format<format::Json, T>, W> { + Layer { + fmt_event: self.fmt_event.with_span_list(display_span_list), + fmt_fields: format::JsonFields::new(), + ..self + } + } +} + +impl<S, N, E, W> Layer<S, N, E, W> { + /// Sets the field formatter that the layer being built will use to record + /// fields. + pub fn fmt_fields<N2>(self, fmt_fields: N2) -> Layer<S, N2, E, W> + where + N2: for<'writer> FormatFields<'writer> + 'static, + { + Layer { + fmt_event: self.fmt_event, + fmt_fields, + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } + + /// Updates the field formatter by applying a function to the existing field formatter. + /// + /// This sets the field formatter that the layer being built will use to record fields. + /// + /// # Examples + /// + /// Updating a field formatter: + /// + /// ```rust + /// use tracing_subscriber::field::MakeExt; + /// let layer = tracing_subscriber::fmt::layer() + /// .map_fmt_fields(|f| f.debug_alt()); + /// # // this is necessary for type inference. + /// # use tracing_subscriber::Layer as _; + /// # let _ = layer.with_subscriber(tracing_subscriber::registry::Registry::default()); + /// ``` + pub fn map_fmt_fields<N2>(self, f: impl FnOnce(N) -> N2) -> Layer<S, N2, E, W> + where + N2: for<'writer> FormatFields<'writer> + 'static, + { + Layer { + fmt_event: self.fmt_event, + fmt_fields: f(self.fmt_fields), + fmt_span: self.fmt_span, + make_writer: self.make_writer, + is_ansi: self.is_ansi, + log_internal_errors: self.log_internal_errors, + _inner: self._inner, + } + } +} + +impl<S> Default for Layer<S> { + fn default() -> Self { + Layer { + fmt_fields: format::DefaultFields::default(), + fmt_event: format::Format::default(), + fmt_span: format::FmtSpanConfig::default(), + make_writer: io::stdout, + is_ansi: cfg!(feature = "ansi"), + log_internal_errors: false, + _inner: PhantomData, + } + } +} + +impl<S, N, E, W> Layer<S, N, E, W> +where + S: Subscriber + for<'a> LookupSpan<'a>, + N: for<'writer> FormatFields<'writer> + 'static, + E: FormatEvent<S, N> + 'static, + W: for<'writer> MakeWriter<'writer> + 'static, +{ + #[inline] + fn make_ctx<'a>(&'a self, ctx: Context<'a, S>, event: &'a Event<'a>) -> FmtContext<'a, S, N> { + FmtContext { + ctx, + fmt_fields: &self.fmt_fields, + event, + } + } +} + +/// A formatted representation of a span's fields stored in its [extensions]. +/// +/// Because `FormattedFields` is generic over the type of the formatter that +/// produced it, multiple versions of a span's formatted fields can be stored in +/// the [`Extensions`][extensions] type-map. This means that when multiple +/// formatters are in use, each can store its own formatted representation +/// without conflicting. +/// +/// [extensions]: crate::registry::Extensions +#[derive(Default)] +pub struct FormattedFields<E: ?Sized> { + _format_fields: PhantomData<fn(E)>, + was_ansi: bool, + /// The formatted fields of a span. + pub fields: String, +} + +impl<E: ?Sized> FormattedFields<E> { + /// Returns a new `FormattedFields`. + pub fn new(fields: String) -> Self { + Self { + fields, + was_ansi: false, + _format_fields: PhantomData, + } + } + + /// Returns a new [`format::Writer`] for writing to this `FormattedFields`. + /// + /// The returned [`format::Writer`] can be used with the + /// [`FormatFields::format_fields`] method. + pub fn as_writer(&mut self) -> format::Writer<'_> { + format::Writer::new(&mut self.fields).with_ansi(self.was_ansi) + } +} + +impl<E: ?Sized> fmt::Debug for FormattedFields<E> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("FormattedFields") + .field("fields", &self.fields) + .field("formatter", &format_args!("{}", std::any::type_name::<E>())) + .field("was_ansi", &self.was_ansi) + .finish() + } +} + +impl<E: ?Sized> fmt::Display for FormattedFields<E> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + fmt::Display::fmt(&self.fields, f) + } +} + +impl<E: ?Sized> Deref for FormattedFields<E> { + type Target = String; + fn deref(&self) -> &Self::Target { + &self.fields + } +} + +// === impl FmtLayer === + +macro_rules! with_event_from_span { + ($id:ident, $span:ident, $($field:literal = $value:expr),*, |$event:ident| $code:block) => { + let meta = $span.metadata(); + let cs = meta.callsite(); + let fs = field::FieldSet::new(&[$($field),*], cs); + #[allow(unused)] + let mut iter = fs.iter(); + let v = [$( + (&iter.next().unwrap(), Some(&$value as &dyn field::Value)), + )*]; + let vs = fs.value_set(&v); + let $event = Event::new_child_of($id, meta, &vs); + $code + }; +} + +impl<S, N, E, W> layer::Layer<S> for Layer<S, N, E, W> +where + S: Subscriber + for<'a> LookupSpan<'a>, + N: for<'writer> FormatFields<'writer> + 'static, + E: FormatEvent<S, N> + 'static, + W: for<'writer> MakeWriter<'writer> + 'static, +{ + fn on_new_span(&self, attrs: &Attributes<'_>, id: &Id, ctx: Context<'_, S>) { + let span = ctx.span(id).expect("Span not found, this is a bug"); + let mut extensions = span.extensions_mut(); + + if extensions.get_mut::<FormattedFields<N>>().is_none() { + let mut fields = FormattedFields::<N>::new(String::new()); + if self + .fmt_fields + .format_fields(fields.as_writer().with_ansi(self.is_ansi), attrs) + .is_ok() + { + fields.was_ansi = self.is_ansi; + extensions.insert(fields); + } else { + eprintln!( + "[tracing-subscriber] Unable to format the following event, ignoring: {:?}", + attrs + ); + } + } + + if self.fmt_span.fmt_timing + && self.fmt_span.trace_close() + && extensions.get_mut::<Timings>().is_none() + { + extensions.insert(Timings::new()); + } + + if self.fmt_span.trace_new() { + with_event_from_span!(id, span, "message" = "new", |event| { + drop(extensions); + drop(span); + self.on_event(&event, ctx); + }); + } + } + + fn on_record(&self, id: &Id, values: &Record<'_>, ctx: Context<'_, S>) { + let span = ctx.span(id).expect("Span not found, this is a bug"); + let mut extensions = span.extensions_mut(); + if let Some(fields) = extensions.get_mut::<FormattedFields<N>>() { + let _ = self.fmt_fields.add_fields(fields, values); + return; + } + + let mut fields = FormattedFields::<N>::new(String::new()); + if self + .fmt_fields + .format_fields(fields.as_writer().with_ansi(self.is_ansi), values) + .is_ok() + { + fields.was_ansi = self.is_ansi; + extensions.insert(fields); + } + } + + fn on_enter(&self, id: &Id, ctx: Context<'_, S>) { + if self.fmt_span.trace_enter() || self.fmt_span.trace_close() && self.fmt_span.fmt_timing { + let span = ctx.span(id).expect("Span not found, this is a bug"); + let mut extensions = span.extensions_mut(); + if let Some(timings) = extensions.get_mut::<Timings>() { + let now = Instant::now(); + timings.idle += (now - timings.last).as_nanos() as u64; + timings.last = now; + } + + if self.fmt_span.trace_enter() { + with_event_from_span!(id, span, "message" = "enter", |event| { + drop(extensions); + drop(span); + self.on_event(&event, ctx); + }); + } + } + } + + fn on_exit(&self, id: &Id, ctx: Context<'_, S>) { + if self.fmt_span.trace_exit() || self.fmt_span.trace_close() && self.fmt_span.fmt_timing { + let span = ctx.span(id).expect("Span not found, this is a bug"); + let mut extensions = span.extensions_mut(); + if let Some(timings) = extensions.get_mut::<Timings>() { + let now = Instant::now(); + timings.busy += (now - timings.last).as_nanos() as u64; + timings.last = now; + } + + if self.fmt_span.trace_exit() { + with_event_from_span!(id, span, "message" = "exit", |event| { + drop(extensions); + drop(span); + self.on_event(&event, ctx); + }); + } + } + } + + fn on_close(&self, id: Id, ctx: Context<'_, S>) { + if self.fmt_span.trace_close() { + let span = ctx.span(&id).expect("Span not found, this is a bug"); + let extensions = span.extensions(); + if let Some(timing) = extensions.get::<Timings>() { + let Timings { + busy, + mut idle, + last, + } = *timing; + idle += (Instant::now() - last).as_nanos() as u64; + + let t_idle = field::display(TimingDisplay(idle)); + let t_busy = field::display(TimingDisplay(busy)); + + with_event_from_span!( + id, + span, + "message" = "close", + "time.busy" = t_busy, + "time.idle" = t_idle, + |event| { + drop(extensions); + drop(span); + self.on_event(&event, ctx); + } + ); + } else { + with_event_from_span!(id, span, "message" = "close", |event| { + drop(extensions); + drop(span); + self.on_event(&event, ctx); + }); + } + } + } + + fn on_event(&self, event: &Event<'_>, ctx: Context<'_, S>) { + thread_local! { + static BUF: RefCell<String> = RefCell::new(String::new()); + } + + BUF.with(|buf| { + let borrow = buf.try_borrow_mut(); + let mut a; + let mut b; + let mut buf = match borrow { + Ok(buf) => { + a = buf; + &mut *a + } + _ => { + b = String::new(); + &mut b + } + }; + + let ctx = self.make_ctx(ctx, event); + if self + .fmt_event + .format_event( + &ctx, + format::Writer::new(&mut buf).with_ansi(self.is_ansi), + event, + ) + .is_ok() + { + let mut writer = self.make_writer.make_writer_for(event.metadata()); + let res = io::Write::write_all(&mut writer, buf.as_bytes()); + if self.log_internal_errors { + if let Err(e) = res { + eprintln!("[tracing-subscriber] Unable to write an event to the Writer for this Subscriber! Error: {}\n", e); + } + } + } else if self.log_internal_errors { + let err_msg = format!("Unable to format the following event. Name: {}; Fields: {:?}\n", + event.metadata().name(), event.fields()); + let mut writer = self.make_writer.make_writer_for(event.metadata()); + let res = io::Write::write_all(&mut writer, err_msg.as_bytes()); + if let Err(e) = res { + eprintln!("[tracing-subscriber] Unable to write an \"event formatting error\" to the Writer for this Subscriber! Error: {}\n", e); + } + } + + buf.clear(); + }); + } + + unsafe fn downcast_raw(&self, id: TypeId) -> Option<*const ()> { + // This `downcast_raw` impl allows downcasting a `fmt` layer to any of + // its components (event formatter, field formatter, and `MakeWriter`) + // as well as to the layer's type itself. The potential use-cases for + // this *may* be somewhat niche, though... + match () { + _ if id == TypeId::of::<Self>() => Some(self as *const Self as *const ()), + _ if id == TypeId::of::<E>() => Some(&self.fmt_event as *const E as *const ()), + _ if id == TypeId::of::<N>() => Some(&self.fmt_fields as *const N as *const ()), + _ if id == TypeId::of::<W>() => Some(&self.make_writer as *const W as *const ()), + _ => None, + } + } +} + +/// Provides the current span context to a formatter. +pub struct FmtContext<'a, S, N> { + pub(crate) ctx: Context<'a, S>, + pub(crate) fmt_fields: &'a N, + pub(crate) event: &'a Event<'a>, +} + +impl<'a, S, N> fmt::Debug for FmtContext<'a, S, N> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("FmtContext").finish() + } +} + +impl<'cx, 'writer, S, N> FormatFields<'writer> for FmtContext<'cx, S, N> +where + S: Subscriber + for<'lookup> LookupSpan<'lookup>, + N: FormatFields<'writer> + 'static, +{ + fn format_fields<R: RecordFields>( + &self, + writer: format::Writer<'writer>, + fields: R, + ) -> fmt::Result { + self.fmt_fields.format_fields(writer, fields) + } +} + +impl<'a, S, N> FmtContext<'a, S, N> +where + S: Subscriber + for<'lookup> LookupSpan<'lookup>, + N: for<'writer> FormatFields<'writer> + 'static, +{ + /// Visits every span in the current context with a closure. + /// + /// The provided closure will be called first with the current span, + /// and then with that span's parent, and then that span's parent, + /// and so on until a root span is reached. + pub fn visit_spans<E, F>(&self, mut f: F) -> Result<(), E> + where + F: FnMut(&SpanRef<'_, S>) -> Result<(), E>, + { + // visit all the current spans + if let Some(scope) = self.event_scope() { + for span in scope.from_root() { + f(&span)?; + } + } + Ok(()) + } + + /// Returns metadata for the span with the given `id`, if it exists. + /// + /// If this returns `None`, then no span exists for that ID (either it has + /// closed or the ID is invalid). + #[inline] + pub fn metadata(&self, id: &Id) -> Option<&'static Metadata<'static>> + where + S: for<'lookup> LookupSpan<'lookup>, + { + self.ctx.metadata(id) + } + + /// Returns [stored data] for the span with the given `id`, if it exists. + /// + /// If this returns `None`, then no span exists for that ID (either it has + /// closed or the ID is invalid). + /// + /// [stored data]: crate::registry::SpanRef + #[inline] + pub fn span(&self, id: &Id) -> Option<SpanRef<'_, S>> + where + S: for<'lookup> LookupSpan<'lookup>, + { + self.ctx.span(id) + } + + /// Returns `true` if an active span exists for the given `Id`. + #[inline] + pub fn exists(&self, id: &Id) -> bool + where + S: for<'lookup> LookupSpan<'lookup>, + { + self.ctx.exists(id) + } + + /// Returns [stored data] for the span that the wrapped subscriber considers + /// to be the current. + /// + /// If this returns `None`, then we are not currently within a span. + /// + /// [stored data]: crate::registry::SpanRef + #[inline] + pub fn lookup_current(&self) -> Option<SpanRef<'_, S>> + where + S: for<'lookup> LookupSpan<'lookup>, + { + self.ctx.lookup_current() + } + + /// Returns the current span for this formatter. + pub fn current_span(&self) -> Current { + self.ctx.current_span() + } + + /// Returns [stored data] for the parent span of the event currently being + /// formatted. + /// + /// If the event has a contextual parent, this will return the current span. If + /// the event has an explicit parent span, this will return that span. If + /// the event does not have a parent span, this will return `None`. + /// + /// [stored data]: SpanRef + pub fn parent_span(&self) -> Option<SpanRef<'_, S>> { + self.ctx.event_span(self.event) + } + + /// Returns an iterator over the [stored data] for all the spans in the + /// current context, starting with the specified span and ending with the + /// root of the trace tree and ending with the current span. + /// + /// This is equivalent to the [`Context::span_scope`] method. + /// + /// <div class="information"> + /// <div class="tooltip ignore" style="">ⓘ<span class="tooltiptext">Note</span></div> + /// </div> + /// <div class="example-wrap" style="display:inline-block"> + /// <pre class="ignore" style="white-space:normal;font:inherit;"> + /// <strong>Note</strong>: Compared to <a href="#method.scope"><code>scope</code></a> this + /// returns the spans in reverse order (from leaf to root). Use + /// <a href="../registry/struct.Scope.html#method.from_root"><code>Scope::from_root</code></a> + /// in case root-to-leaf ordering is desired. + /// </pre></div> + /// + /// <div class="example-wrap" style="display:inline-block"> + /// <pre class="ignore" style="white-space:normal;font:inherit;"> + /// <strong>Note</strong>: This requires the wrapped subscriber to implement the + /// <a href="../registry/trait.LookupSpan.html"><code>LookupSpan</code></a> trait. + /// See the documentation on <a href="./struct.Context.html"><code>Context</code>'s + /// declaration</a> for details. + /// </pre></div> + /// + /// [stored data]: crate::registry::SpanRef + pub fn span_scope(&self, id: &Id) -> Option<registry::Scope<'_, S>> + where + S: for<'lookup> LookupSpan<'lookup>, + { + self.ctx.span_scope(id) + } + + /// Returns an iterator over the [stored data] for all the spans in the + /// event's span context, starting with its parent span and ending with the + /// root of the trace tree. + /// + /// This is equivalent to calling the [`Context::event_scope`] method and + /// passing the event currently being formatted. + /// + /// <div class="example-wrap" style="display:inline-block"> + /// <pre class="ignore" style="white-space:normal;font:inherit;"> + /// <strong>Note</strong>: Compared to <a href="#method.scope"><code>scope</code></a> this + /// returns the spans in reverse order (from leaf to root). Use + /// <a href="../registry/struct.Scope.html#method.from_root"><code>Scope::from_root</code></a> + /// in case root-to-leaf ordering is desired. + /// </pre></div> + /// + /// <div class="example-wrap" style="display:inline-block"> + /// <pre class="ignore" style="white-space:normal;font:inherit;"> + /// <strong>Note</strong>: This requires the wrapped subscriber to implement the + /// <a href="../registry/trait.LookupSpan.html"><code>LookupSpan</code></a> trait. + /// See the documentation on <a href="./struct.Context.html"><code>Context</code>'s + /// declaration</a> for details. + /// </pre></div> + /// + /// [stored data]: crate::registry::SpanRef + pub fn event_scope(&self) -> Option<registry::Scope<'_, S>> + where + S: for<'lookup> registry::LookupSpan<'lookup>, + { + self.ctx.event_scope(self.event) + } + + /// Returns the [field formatter] configured by the subscriber invoking + /// `format_event`. + /// + /// The event formatter may use the returned field formatter to format the + /// fields of any events it records. + /// + /// [field formatter]: FormatFields + pub fn field_format(&self) -> &N { + self.fmt_fields + } +} + +struct Timings { + idle: u64, + busy: u64, + last: Instant, +} + +impl Timings { + fn new() -> Self { + Self { + idle: 0, + busy: 0, + last: Instant::now(), + } + } +} + +#[cfg(test)] +mod test { + use super::*; + use crate::fmt::{ + self, + format::{self, test::MockTime, Format}, + layer::Layer as _, + test::{MockMakeWriter, MockWriter}, + time, + }; + use crate::Registry; + use format::FmtSpan; + use regex::Regex; + use tracing::subscriber::with_default; + use tracing_core::dispatcher::Dispatch; + + #[test] + fn impls() { + let f = Format::default().with_timer(time::Uptime::default()); + let fmt = fmt::Layer::default().event_format(f); + let subscriber = fmt.with_subscriber(Registry::default()); + let _dispatch = Dispatch::new(subscriber); + + let f = format::Format::default(); + let fmt = fmt::Layer::default().event_format(f); + let subscriber = fmt.with_subscriber(Registry::default()); + let _dispatch = Dispatch::new(subscriber); + + let f = format::Format::default().compact(); + let fmt = fmt::Layer::default().event_format(f); + let subscriber = fmt.with_subscriber(Registry::default()); + let _dispatch = Dispatch::new(subscriber); + } + + #[test] + fn fmt_layer_downcasts() { + let f = format::Format::default(); + let fmt = fmt::Layer::default().event_format(f); + let subscriber = fmt.with_subscriber(Registry::default()); + + let dispatch = Dispatch::new(subscriber); + assert!(dispatch.downcast_ref::<fmt::Layer<Registry>>().is_some()); + } + + #[test] + fn fmt_layer_downcasts_to_parts() { + let f = format::Format::default(); + let fmt = fmt::Layer::default().event_format(f); + let subscriber = fmt.with_subscriber(Registry::default()); + let dispatch = Dispatch::new(subscriber); + assert!(dispatch.downcast_ref::<format::DefaultFields>().is_some()); + assert!(dispatch.downcast_ref::<format::Format>().is_some()) + } + + #[test] + fn is_lookup_span() { + fn assert_lookup_span<T: for<'a> crate::registry::LookupSpan<'a>>(_: T) {} + let fmt = fmt::Layer::default(); + let subscriber = fmt.with_subscriber(Registry::default()); + assert_lookup_span(subscriber) + } + + fn sanitize_timings(s: String) -> String { + let re = Regex::new("time\\.(idle|busy)=([0-9.]+)[mµn]s").unwrap(); + re.replace_all(s.as_str(), "timing").to_string() + } + + #[test] + fn format_error_print_to_stderr() { + struct AlwaysError; + + impl std::fmt::Debug for AlwaysError { + fn fmt(&self, _f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result { + Err(std::fmt::Error) + } + } + + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + .finish(); + + with_default(subscriber, || { + tracing::info!(?AlwaysError); + }); + let actual = sanitize_timings(make_writer.get_string()); + + // Only assert the start because the line number and callsite may change. + let expected = concat!("Unable to format the following event. Name: event ", file!(), ":"); + assert!(actual.as_str().starts_with(expected), "\nactual = {}\nshould start with expected = {}\n", actual, expected); + } + + #[test] + fn format_error_ignore_if_log_internal_errors_is_false() { + struct AlwaysError; + + impl std::fmt::Debug for AlwaysError { + fn fmt(&self, _f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result { + Err(std::fmt::Error) + } + } + + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + .log_internal_errors(false) + .finish(); + + with_default(subscriber, || { + tracing::info!(?AlwaysError); + }); + let actual = sanitize_timings(make_writer.get_string()); + assert_eq!("", actual.as_str()); + } + + #[test] + fn synthesize_span_none() { + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + // check that FmtSpan::NONE is the default + .finish(); + + with_default(subscriber, || { + let span1 = tracing::info_span!("span1", x = 42); + let _e = span1.enter(); + }); + let actual = sanitize_timings(make_writer.get_string()); + assert_eq!("", actual.as_str()); + } + + #[test] + fn synthesize_span_active() { + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + .with_span_events(FmtSpan::ACTIVE) + .finish(); + + with_default(subscriber, || { + let span1 = tracing::info_span!("span1", x = 42); + let _e = span1.enter(); + }); + let actual = sanitize_timings(make_writer.get_string()); + assert_eq!( + "fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: enter\n\ + fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: exit\n", + actual.as_str() + ); + } + + #[test] + fn synthesize_span_close() { + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + .with_span_events(FmtSpan::CLOSE) + .finish(); + + with_default(subscriber, || { + let span1 = tracing::info_span!("span1", x = 42); + let _e = span1.enter(); + }); + let actual = sanitize_timings(make_writer.get_string()); + assert_eq!( + "fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: close timing timing\n", + actual.as_str() + ); + } + + #[test] + fn synthesize_span_close_no_timing() { + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + .without_time() + .with_span_events(FmtSpan::CLOSE) + .finish(); + + with_default(subscriber, || { + let span1 = tracing::info_span!("span1", x = 42); + let _e = span1.enter(); + }); + let actual = sanitize_timings(make_writer.get_string()); + assert_eq!( + "span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: close\n", + actual.as_str() + ); + } + + #[test] + fn synthesize_span_full() { + let make_writer = MockMakeWriter::default(); + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer.clone()) + .with_level(false) + .with_ansi(false) + .with_timer(MockTime) + .with_span_events(FmtSpan::FULL) + .finish(); + + with_default(subscriber, || { + let span1 = tracing::info_span!("span1", x = 42); + let _e = span1.enter(); + }); + let actual = sanitize_timings(make_writer.get_string()); + assert_eq!( + "fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: new\n\ + fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: enter\n\ + fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: exit\n\ + fake time span1{x=42}: tracing_subscriber::fmt::fmt_layer::test: close timing timing\n", + actual.as_str() + ); + } + + #[test] + fn make_writer_based_on_meta() { + struct MakeByTarget { + make_writer1: MockMakeWriter, + make_writer2: MockMakeWriter, + } + + impl<'a> MakeWriter<'a> for MakeByTarget { + type Writer = MockWriter; + + fn make_writer(&'a self) -> Self::Writer { + self.make_writer1.make_writer() + } + + fn make_writer_for(&'a self, meta: &Metadata<'_>) -> Self::Writer { + if meta.target() == "writer2" { + return self.make_writer2.make_writer(); + } + self.make_writer() + } + } + + let make_writer1 = MockMakeWriter::default(); + let make_writer2 = MockMakeWriter::default(); + + let make_writer = MakeByTarget { + make_writer1: make_writer1.clone(), + make_writer2: make_writer2.clone(), + }; + + let subscriber = crate::fmt::Subscriber::builder() + .with_writer(make_writer) + .with_level(false) + .with_target(false) + .with_ansi(false) + .with_timer(MockTime) + .with_span_events(FmtSpan::CLOSE) + .finish(); + + with_default(subscriber, || { + let span1 = tracing::info_span!("writer1_span", x = 42); + let _e = span1.enter(); + tracing::info!(target: "writer2", "hello writer2!"); + let span2 = tracing::info_span!(target: "writer2", "writer2_span"); + let _e = span2.enter(); + tracing::warn!(target: "writer1", "hello writer1!"); + }); + + let actual = sanitize_timings(make_writer1.get_string()); + assert_eq!( + "fake time writer1_span{x=42}:writer2_span: hello writer1!\n\ + fake time writer1_span{x=42}: close timing timing\n", + actual.as_str() + ); + let actual = sanitize_timings(make_writer2.get_string()); + assert_eq!( + "fake time writer1_span{x=42}: hello writer2!\n\ + fake time writer1_span{x=42}:writer2_span: close timing timing\n", + actual.as_str() + ); + } +} |