Struct `Event`

pub struct Event<'a> { /* private fields */ }

Events represent single points in time where something occurred during the execution of a program.

An Event can be compared to a log record in unstructured logging, but with two key differences:

Events exist within the context of a span. Unlike log lines, they may be located within the trace tree, allowing visibility into the temporal context in which the event occurred, as well as the source code location.
Like spans, Events have structured key-value data known as fields, which may include textual message. In general, a majority of the data associated with an event should be in the event's fields rather than in the textual message, as the fields are more structured.

Implementations

`impl<'a> Event<'a>`

fn dispatch(metadata: &'static Metadata<'static>, fields: &'a ValueSet<'_>)

Constructs a new Event with the specified metadata and set of values, and observes it with the current subscriber.

fn new(metadata: &'static Metadata<'static>, fields: &'a ValueSet<'a>) -> Self

Returns a new Event in the current span, with the specified metadata and set of values.

fn new_child_of(parent: impl Into<Option<Id>>, metadata: &'static Metadata<'static>, fields: &'a ValueSet<'a>) -> Self

Returns a new Event as a child of the specified span, with the provided metadata and set of values.

fn child_of(parent: impl Into<Option<Id>>, metadata: &'static Metadata<'static>, fields: &'a ValueSet<'_>)

Constructs a new Event with the specified metadata and set of values, and observes it with the current subscriber and an explicit parent.

fn record(&self, visitor: &mut dyn Visit)

Visits all the fields on this Event with the specified visitor.

fn fields(&self) -> Iter

Returns an iterator over the set of values on this Event.

fn metadata(&self) -> &'static Metadata<'static>

Returns metadata describing this Event.

fn is_root(&self) -> bool

Returns true if the new event should be a root.

fn is_contextual(&self) -> bool

Returns true if the new event's parent should be determined based on the current context.

If this is true and the current thread is currently inside a span, then that span should be the new event's parent. Otherwise, if the current thread is not inside a span, then the new event will be the root of its own trace tree.

fn parent(&self) -> Option<&Id>

Returns the new event's explicitly-specified parent, if there is one.

Otherwise (if the new event is a root or is a child of the current span), returns None.

Trait Implementations

`impl<'a> Debug for Event<'a>`

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

Auto Trait Implementations

`impl<'a> !RefUnwindSafe for Event<'a>`

`impl<'a> !Send for Event<'a>`

`impl<'a> !Sync for Event<'a>`

`impl<'a> !UnwindSafe for Event<'a>`

`impl<'a> Freeze for Event<'a>`

`impl<'a> Unpin for Event<'a>`

`impl<'a> UnsafeUnpin for Event<'a>`

Blanket Implementations

`impl<T> Any for Event<'a> where T: 'static + ?Sized,`

fn type_id(&self) -> TypeId

`impl<T> Borrow<T> for Event<'a> where T: ?Sized,`

fn borrow(&self) -> &T

`impl<T> BorrowMut<T> for Event<'a> where T: ?Sized,`

fn borrow_mut(&mut self) -> &mut T

`impl<T> From<T> for Event<'a>`

fn from(t: T) -> T: Returns the argument unchanged.

`impl<T, U> Into for Event<'a> where U: From<T>,`

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of [From]<T> for U chooses to do.

`impl<T, U> TryFrom for Event<'a> where U: Into<T>,`

type Error = never;
fn try_from(value: U) -> Result<T, never>

`impl<T, U> TryInto for Event<'a> where U: TryFrom<T>,`

type Error = >::Error;
fn try_into(self) -> Result<U, >::Error>