Struct tracing::event::Event

source ·
pub struct Event<'a> { /* private fields */ }
Expand description

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§

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

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

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

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

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

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

Returns metadata describing this Event.

Returns true if the new event should be a root.

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.

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§

Formats the value using the given formatter. Read more

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more
Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Calls U::from(self).

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

The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.
Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more
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