Struct SpanCtxt 

pub struct SpanCtxt { /* private fields */ }

The trace id, span id, and parent span id of a span.

These ids can be used to identify the distributed trace a span belongs to, and to identify the span itself within that trace.

The SpanCtxt for the currently executing span can be pulled from the ambient context with SpanCtxt::current. Once a SpanCtxt is constructed, a new child context can be generated by SpanCtxt::new_child.

SpanCtxt should be pushed onto the ambient context with SpanCtxt::push so any events emitted during its execution are correlated to it.

Implementations

impl SpanCtxt

pub const fn new( trace_id: Option<TraceId>, span_parent: Option<SpanId>, span_id: Option<SpanId>, ) -> Self

Create the context from a set of identifiers.

The trace_id and span_id should both be Some, but span_parent may be None if the span is at the root of the distributed trace.

If trace_id or span_id are None then the context is invalid, but can still be used.

pub const fn empty() -> Self

Create a context where all identifiers are None.

pub fn new_root(rng: impl Rng) -> Self

Generate a new context.

pub fn current(ctxt: impl Ctxt) -> Self

Read the current context from an ambient Ctxt.

This method will pull the TraceId from KEY_TRACE_ID, the SpanId from KEY_SPAN_ID, and the parent SpanId from KEY_SPAN_PARENT.

pub fn new_child(&self, rng: impl Rng) -> Self

Generate a new context that is a child of self.

The new context will share the same trace id as self, use the span id of self as its parent span id, and generate a new random span id as its own through SpanId::random.

If Self::trace_id is None then a new trace id will be generated through TraceId::random.

pub fn trace_id(&self) -> Option<&TraceId>

Get the trace id for the span.

pub fn span_parent(&self) -> Option<&SpanId>

Get the parent of the span.

pub fn span_id(&self) -> Option<&SpanId>

Get the id of the span.

pub fn push<T: Ctxt>(&self, ctxt: T) -> Frame<T>

Push the SpanCtxt onto the ambient context.

The trace id, span id, and parent span id will be pushed to the context. This ensures diagnostics emitted during the execution of this span are properly linked to it.

Trait Implementations

impl Clone for SpanCtxt

fn clone(&self) -> SpanCtxt

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SpanCtxt

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Hash for SpanCtxt

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for SpanCtxt

fn eq(&self, other: &SpanCtxt) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Props for SpanCtxt

fn for_each<'kv, F: FnMut(Str<'kv>, Value<'kv>) -> ControlFlow<()>>( &'kv self, for_each: F, ) -> ControlFlow<()>

Enumerate the Str and Value pairs.

fn get<'v, K>(&'v self, key: K) -> Option<Value<'v>>

where K: ToStr,

Get the value for a given key, if it’s present.

fn pull<'kv, V, K>(&'kv self, key: K) -> Option<V>

where V: FromValue<'kv>, K: ToStr,

Get the value for a given key, if it’s present as an instance of V.

fn and_props<U>(self, other: U) -> And<Self, U>

where U: Props, Self: Sized,

Concatenate other to the end of self.

fn filter<F>(self, filter: F) -> Filter<Self, F>

where F: Fn(Str<'_>, Value<'_>) -> bool, Self: Sized,

Filter the set of properties.

fn collect<'kv, C>(&'kv self) -> C

where C: FromProps<'kv>,

Collect these properties into another collection type.

fn as_map(&self) -> &AsMap<Self>

where Self: Sized,

Get an adapter that will serialize properties as a map.

fn dedup(&self) -> &Dedup<Self>

where Self: Sized,

Lazily de-duplicate properties in the collection.

fn is_unique(&self) -> bool

Whether the collection is known not to contain any duplicate keys.

fn size(&self) -> Option<usize>

A hint on the number of properties in the collection.

impl Copy for SpanCtxt

impl Eq for SpanCtxt

impl StructuralPartialEq for SpanCtxt