Struct opentelemetry::trace::TraceState

pub struct TraceState(_);

TraceState carries system-specific configuration data, represented as a list of key-value pairs. TraceState allows multiple tracing systems to participate in the same trace.

Please review the W3C specification for details on this field.

Implementations

impl TraceState

pub fn from_key_value<T, K, V>(trace_state: T) -> Result<Self, ()> where
    T: IntoIterator<Item = (K, V)>,
    K: ToString,
    V: ToString, 

Creates a new TraceState from the given key-value collection.

Examples

use opentelemetry::trace::TraceState;

let kvs = vec![("foo", "bar"), ("apple", "banana")];
let trace_state: Result<TraceState, ()> = TraceState::from_key_value(kvs);

assert!(trace_state.is_ok());
assert_eq!(trace_state.unwrap().header(), String::from("foo=bar,apple=banana"))

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

Retrieves a value for a given key from the TraceState if it exists.

pub fn insert(&self, key: String, value: String) -> Result<TraceState, ()>

Inserts the given key-value pair into the TraceState. If a value already exists for the given key, this updates the value and updates the value's position. If the key or value are invalid per the W3 Spec an Err is returned, else a new TraceState with the updated key/value is returned.

pub fn delete(&self, key: String) -> Result<TraceState, ()>

Removes the given key-value pair from the TraceState. If the key is invalid per the W3 Spec or the key does not exist an Err is returned. Else, a new TraceState with the removed entry is returned.

pub fn header(&self) -> String

Creates a new TraceState header string, delimiting each key and value with a = and each entry with a ,.

pub fn header_delimited(
    &self,
    entry_delimiter: &str,
    list_delimiter: &str
) -> String

Creates a new TraceState header string, with the given key/value delimiter and entry delimiter.

Trait Implementations

impl Clone for TraceState

fn clone(&self) -> TraceState

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for TraceState

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

Formats the value using the given formatter.

impl Default for TraceState

fn default() -> TraceState

Returns the "default value" for a type.

impl Eq for TraceState

impl FromStr for TraceState

type Err = ()

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl PartialEq<TraceState> for TraceState

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

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

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

This method tests for !=.

impl StructuralEq for TraceState

impl StructuralPartialEq for TraceState