Struct tracing_subscriber::registry::SpanRef
source · [−]pub struct SpanRef<'a, R: LookupSpan<'a>> { /* private fields */ }
Expand description
Implementations
sourceimpl<'a, R> SpanRef<'a, R> where
R: LookupSpan<'a>,
impl<'a, R> SpanRef<'a, R> where
R: LookupSpan<'a>,
sourcepub fn metadata(&self) -> &'static Metadata<'static>
pub fn metadata(&self) -> &'static Metadata<'static>
Returns a static reference to the span’s metadata.
sourcepub fn parent(&self) -> Option<Self>
pub fn parent(&self) -> Option<Self>
Returns a SpanRef
describing this span’s parent, or None
if this
span is the root of its trace tree.
sourcepub fn scope(&self) -> Scope<'a, R>ⓘNotable traits for Scope<'a, R>impl<'a, R> Iterator for Scope<'a, R> where
R: LookupSpan<'a>, type Item = SpanRef<'a, R>;
pub fn scope(&self) -> Scope<'a, R>ⓘNotable traits for Scope<'a, R>impl<'a, R> Iterator for Scope<'a, R> where
R: LookupSpan<'a>, type Item = SpanRef<'a, R>;
R: LookupSpan<'a>, type Item = SpanRef<'a, R>;
Returns an iterator over all parents of this span, starting with this span, ordered from leaf to root.
The iterator will first return the span, then the span’s immediate parent, followed by that span’s parent, and so on, until it reaches a root span.
use tracing::{span, Subscriber};
use tracing_subscriber::{
layer::{Context, Layer},
prelude::*,
registry::LookupSpan,
};
struct PrintingLayer;
impl<S> Layer<S> for PrintingLayer
where
S: Subscriber + for<'lookup> LookupSpan<'lookup>,
{
fn on_enter(&self, id: &span::Id, ctx: Context<S>) {
let span = ctx.span(id).unwrap();
let scope = span.scope().map(|span| span.name()).collect::<Vec<_>>();
println!("Entering span: {:?}", scope);
}
}
tracing::subscriber::with_default(tracing_subscriber::registry().with(PrintingLayer), || {
let _root = tracing::info_span!("root").entered();
// Prints: Entering span: ["root"]
let _child = tracing::info_span!("child").entered();
// Prints: Entering span: ["child", "root"]
let _leaf = tracing::info_span!("leaf").entered();
// Prints: Entering span: ["leaf", "child", "root"]
});
If the opposite order (from the root to this span) is desired, calling Scope::from_root
on
the returned iterator reverses the order.
impl<S> Layer<S> for PrintingLayer
where
S: Subscriber + for<'lookup> LookupSpan<'lookup>,
{
fn on_enter(&self, id: &span::Id, ctx: Context<S>) {
let span = ctx.span(id).unwrap();
let scope = span.scope().from_root().map(|span| span.name()).collect::<Vec<_>>();
println!("Entering span: {:?}", scope);
}
}
tracing::subscriber::with_default(tracing_subscriber::registry().with(PrintingLayer), || {
let _root = tracing::info_span!("root").entered();
// Prints: Entering span: ["root"]
let _child = tracing::info_span!("child").entered();
// Prints: Entering span: ["root", "child"]
let _leaf = tracing::info_span!("leaf").entered();
// Prints: Entering span: ["root", "child", "leaf"]
});
sourcepub fn extensions(&self) -> Extensions<'_>
pub fn extensions(&self) -> Extensions<'_>
Returns a reference to this span’s Extensions
.
The extensions may be used by Layer
s to store additional data
describing the span.
sourcepub fn extensions_mut(&self) -> ExtensionsMut<'_>
pub fn extensions_mut(&self) -> ExtensionsMut<'_>
Returns a mutable reference to this span’s Extensions
.
The extensions may be used by Layer
s to store additional data
describing the span.
Trait Implementations
Auto Trait Implementations
impl<'a, R> RefUnwindSafe for SpanRef<'a, R> where
R: RefUnwindSafe,
<R as LookupSpan<'a>>::Data: RefUnwindSafe,
impl<'a, R> Send for SpanRef<'a, R> where
R: Sync,
<R as LookupSpan<'a>>::Data: Send,
impl<'a, R> Sync for SpanRef<'a, R> where
R: Sync,
<R as LookupSpan<'a>>::Data: Sync,
impl<'a, R> Unpin for SpanRef<'a, R> where
<R as LookupSpan<'a>>::Data: Unpin,
impl<'a, R> UnwindSafe for SpanRef<'a, R> where
R: RefUnwindSafe,
<R as LookupSpan<'a>>::Data: UnwindSafe,
Blanket Implementations
sourceimpl<T> BorrowMut<T> for T where
T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more