Struct tarpc::trace::Context

pub struct Context {
    pub trace_id: TraceId,
    pub span_id: SpanId,
    pub sampling_decision: SamplingDecision,
}

A context for tracing the execution of processes, distributed or otherwise.

Consists of a span identifying an event, an optional parent span identifying a causal event that triggered the current span, and a trace with which all related spans are associated.

Fields

trace_id: TraceId

An identifier of the trace associated with the current context. A trace ID is typically created at a root span and passed along through all causal events.

span_id: SpanId

An identifier of the current span. In typical RPC usage, a span is created by a client before making an RPC, and the span ID is sent to the server. The server is free to create its own spans, for which it sets the client’s span as the parent span.

sampling_decision: SamplingDecision

Indicates whether a sampler has already decided whether or not to sample the trace associated with the Context. If sampling_decision is None, then a decision has not yet been made. Downstream samplers do not need to abide by “no sample” decisions–for example, an upstream client may choose to never sample, which may not make sense for the client’s dependencies. On the other hand, if an upstream process has chosen to sample this trace, then the downstream samplers are expected to respect that decision and also sample the trace. Otherwise, the full trace would not be able to be reconstructed.

Trait Implementations

impl Clone for Context

fn clone(&self) -> Context

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Context

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

Formats the value using the given formatter.

impl Default for Context

fn default() -> Context

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Context

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl From<SpanRef<'_>> for Context

fn from(span: SpanRef<'_>) -> Self

Converts to this type from the input type.

impl Hash for Context

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, 

Feeds a slice of this type into the given Hasher.

impl PartialEq<Context> for Context

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl Serialize for Context

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.

impl TryFrom<&'_ Span> for Context

type Error = NoActiveSpan

The type returned in the event of a conversion error.

fn try_from(span: &Span) -> Result<Self, NoActiveSpan>

Performs the conversion.

impl Copy for Context

impl Eq for Context

impl StructuralEq for Context

impl StructuralPartialEq for Context