Struct TraceCtx 

pub struct TraceCtx {
    pub trace_id: String,
    pub parent_id: Option<String>,
    pub baggage: Vec<BaggageEntry>,
}

In-process trace context for cross-crate correlation.

Wraps a W3C-compatible trace ID and optional parent span ID. Additional bounded baggage can be attached for cross-boundary metadata.

Fields

trace_id: String

The trace ID (W3C: 32 hex chars, or any opaque string for legacy compat).

parent_id: Option<String>

Optional parent span ID (W3C: 16 hex chars).

baggage: Vec<BaggageEntry>

Bounded baggage for cross-boundary metadata. Keys and values must be short ASCII strings. No sensitive data.

Implementations

impl TraceCtx

pub fn generate() -> TraceCtx

Create a new trace context with a generated trace ID (UUID v4 hex).

pub fn from_trace_id(trace_id: impl Into<String>) -> TraceCtx

Create from a raw trace ID string.

pub fn from_legacy_trace_id(legacy_id: impl Into<String>) -> TraceCtx

Create from a legacy TraceId(String) value for migration compatibility.

Phase status: compatibility / migration-only

pub fn to_legacy_trace_id(&self) -> &str

Extract the trace ID as a string for legacy interop.

Phase status: compatibility / migration-only

pub fn with_parent(self, parent_id: impl Into<String>) -> TraceCtx

Set the parent span ID.

pub fn child(&self, span_id: impl Into<String>) -> TraceCtx

Create a child context: same trace ID, new parent.

pub fn add_baggage( &mut self, key: impl Into<String>, value: impl Into<String>, ) -> Result<(), TraceError>

Add a baggage entry. Returns Err if limits are exceeded.

pub fn baggage_value(&self, key: &str) -> Option<&str>

Get a baggage value by key.

pub fn to_traceparent(&self) -> Result<String, TraceError>

Format as a W3C traceparent header.

Format: 00-{trace_id}-{parent_id}-01

If the trace ID is not exactly 32 hex chars (e.g., a legacy opaque string), it is converted via deterministic BLAKE3 hash truncation using hash_to_w3c_trace_id. Padding and truncation are forbidden.

If no parent ID exists, a zero span ID is used. Non-compliant parent IDs (not 16 hex chars) are rejected.

pub fn from_traceparent(header: &str) -> Result<TraceCtx, TraceError>

Parse from a W3C traceparent header.

Format: {version}-{trace_id}-{parent_id}-{flags}

Trait Implementations

impl Clone for TraceCtx

fn clone(&self) -> TraceCtx

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TraceCtx

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for TraceCtx

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for TraceCtx

impl Hash for TraceCtx

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

where __H: Hasher,

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 JsonSchema for TraceCtx

fn schema_name() -> String

The name of the generated JSON Schema.

fn schema_id() -> Cow<'static, str>

Returns a string that uniquely identifies the schema produced by this type.

fn json_schema(generator: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn is_referenceable() -> bool

Whether JSON Schemas generated for this type should be re-used where possible using the $ref keyword.

impl PartialEq for TraceCtx

fn eq(&self, other: &TraceCtx) -> 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 Serialize for TraceCtx

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for TraceCtx