Function layer 

pub fn layer<S>() -> OpenTelemetryLayer<S, NoopTracer>
where
    S: Subscriber + for<'span> LookupSpan<'span>,

Construct a layer to track spans via OpenTelemetry.

It will convert the tracing spans to OpenTelemetry spans and tracing events which are in a span to events in the currently active OpenTelemetry span. Child-Parent links will be automatically translated as well. Follows-From links will also be generated, but only if the originating span has not been closed yet.

Various translations exist between semantic conventions of OpenTelemetry and tracing, such as including level information as fields, or mapping error fields to exceptions. See the various layer().with_* functions for configuration of these features.

Examples

use tracing_subscriber::layer::SubscriberExt;
use tracing_subscriber::Registry;

// Use the tracing subscriber `Registry`, or any other subscriber
// that impls `LookupSpan`
let subscriber = Registry::default().with(tracing_opentelemetry::layer());