Struct metrics::Label

pub struct Label(_, _);

Metadata for a metric key in the for of a key/value pair.

Metrics are always defined by a name, but can optionally be assigned “labels”, which are key/value pairs that provide metadata about the key. Labels are typically used for differentiating the context of when an where a metric are emitted.

For example, in a web service, you might wish to label metrics with the user ID responsible for the request currently being processed, or the request path being processed. Another example may be that if you were running a piece o code that was turned on or off by a feature toggle, you may wish to include a label in metrics to indicate whether or not they were using the feature toggle.

Implementations

impl Label

pub fn new<K, V>(key: K, value: V) -> Self where
    K: Into<SharedString>,
    V: Into<SharedString>, 

Creates a Label from a key and value.

pub const fn from_static_parts(key: &'static str, value: &'static str) -> Self

Creates a Label from a static key and value.

pub fn key(&self) -> &str

Key of this label.

pub fn value(&self) -> &str

Value of this label.

pub fn into_parts(self) -> (SharedString, SharedString)

Consumes this Label, returning the key and value.

Trait Implementations

impl Clone for Label

fn clone(&self) -> Label

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Label

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

Formats the value using the given formatter.

impl<K, V> From<&'_ (K, V)> for Label where
    K: Into<SharedString> + Clone,
    V: Into<SharedString> + Clone, 

fn from(pair: &(K, V)) -> Label

Performs the conversion.

impl Hash for Label

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 Ord for Label

fn cmp(&self, other: &Label) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<Label> for Label

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

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

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

This method tests for !=.

impl PartialOrd<Label> for Label

fn partial_cmp(&self, other: &Label) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]

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

This method tests less than (for self and other) and is used by the < operator.

#[must_use]

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]

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

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for Label

impl StructuralEq for Label

impl StructuralPartialEq for Label