Struct TracingContext

pub struct TracingContext(Context);

Context for tracing used for propagating tracing information in a distributed system.

Generally, the caller of a service should create a tracing context from the current tracing span and pass it to the callee through the network. The callee will then attach its local tracing span as a child of the tracing context, so that the external tracing service can associate them in a single trace.

The tracing context must be serialized into the W3C trace context format and passed in rpc message headers when communication of frontend, datanode and meta.

See Trace Context for more information.

Tuple Fields

0: Context

Implementations

impl TracingContext

pub fn from_span(span: &Span) -> Self

Create a new tracing context from a tracing span.

pub fn from_current_span() -> Self

Create a new tracing context from the current tracing span considered by the subscriber.

pub fn new() -> Self

Create a no-op tracing context.

pub fn attach(&self, span: Span) -> Span

Attach the given span as a child of the context. Returns the attached span.

pub fn to_w3c(&self) -> W3cTrace

Convert the tracing context to the W3C trace context format.

pub fn from_w3c(fields: &W3cTrace) -> Self

Create a new tracing context from the W3C trace context format.

pub fn to_json(&self) -> String

Convert the tracing context to a JSON string in W3C trace context format.

pub fn from_json(json: &str) -> Self

Create a new tracing context from a JSON string in W3C trace context format.

Illegal json string will produce an empty tracing context and no error will be reported.

Trait Implementations

impl Clone for TracingContext

fn clone(&self) -> TracingContext

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for TracingContext

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

Formats the value using the given formatter.

impl Default for TracingContext

fn default() -> Self

Returns the “default value” for a type.