Struct SubscriberBuilder

pub struct SubscriberBuilder { /* private fields */ }

Builder for the trace_tools subscriber.

This can be used to enable/disable Layers provided by this crate.

Implementations

impl SubscriberBuilder

pub fn with_log_layer(self, logger_config: LoggerConfig) -> Self

Enables the LogLayer for this subscriber, using the parameters provided by the given LoggerConfig.

pub fn with_default_log_layer(self) -> Self

Enables the LogLayer for this subscriber, using the default configuration.

pub fn with_flamegraph_layer<P: AsRef<Path>>(self, folded_stack_file: P) -> Self

Enables the FlamegraphLayer for this subscriber.

The given path describes the desired output location of the folded stack file that is generated by this layer during runtime. This file can then be used to produce a flamegraph by a Flamegrapher instance, or by the inferno tool.

pub fn finish(self) -> Result<(TraceSubscriber, Option<Flamegrapher>), Error>

Builds and returns the TraceSubscriber.

Errors

• Creation of the FlamegraphLayer failed.
• Creation of the LogLayer failed.

Notes

• This method calls the collect_logs function. Any log records emitted will be converting into tracing events, and therefore any external functionality that deals with log records may no longer function as expected.
• This method does not set the global subscriber. As such, a call to finish can be used to further extend the return subscriber with external Layers.

pub fn init(self) -> Result<Option<Flamegrapher>, Error>

Builds the TraceSubscriber and sets it as the global default subscriber.

Returns a Result over an Option<Flamegrapher>. The returned option is Some if the LogLayer is enabled and has been successfully initialised. If the `LogLayer has not been enabled with the builder, it is fine to ignore this value.

Errors

• Creation of the FlamegraphLayer failed.
• Creation of the LogLayer failed.

Panics

This method will panic if the flamegraph layer is enabled and the program is not built with --cfg tokio_unstable.

Notes

• This method calls the collect_logs function. Any log records emitted will be converting into tracing events, and therefore any external functionality that deals with log records may no longer function as expected.
• This method sets the global subscriber. Any further attempts to set the global subscriber (including another call to this method) will fail.
• The subscriber initialised by this method cannot be extended.

Trait Implementations

impl Default for SubscriberBuilder

fn default() -> SubscriberBuilder

Returns the “default value” for a type.