Struct tracing_core::event::Event [−][src]
pub struct Event<'a> { /* fields omitted */ }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>[src]
impl<'a> Event<'a>[src]pub fn dispatch(metadata: &'static Metadata<'static>, fields: &'a ValueSet<'_>)[src]
Constructs a new Event with the specified metadata and set of values,
and observes it with the current subscriber.
pub fn new(
metadata: &'static Metadata<'static>,
fields: &'a ValueSet<'a>
) -> Self[src]
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.
pub fn new_child_of(
parent: impl Into<Option<Id>>,
metadata: &'static Metadata<'static>,
fields: &'a ValueSet<'a>
) -> Self[src]
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.
pub fn child_of(
parent: impl Into<Option<Id>>,
metadata: &'static Metadata<'static>,
fields: &'a ValueSet<'_>
)[src]
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.
pub fn record(&self, visitor: &mut dyn Visit)[src]
Visits all the fields on this Event with the specified visitor.
pub fn fields(&self) -> Iterⓘ[src]
Returns an iterator over the set of values on this Event.
pub fn metadata(&self) -> &'static Metadata<'static>[src]
Returns metadata describing this Event.
pub fn is_root(&self) -> bool[src]
Returns true if the new event should be a root.
pub fn is_contextual(&self) -> bool[src]
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.
pub fn parent(&self) -> Option<&Id>[src]
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 false.