Enum ExportFallback 

pub enum ExportFallback {
    None,
    LogError,
    Stdout,
    Stderr,
    File(PathBuf),
    Custom(Arc<dyn FallbackHandler>),
}

Predefined fallback strategies for common scenarios.

Variants

None

Discard failed exports silently.

Use this when telemetry loss is acceptable and you don’t want any overhead from fallback handling.

LogError

Log failed exports via tracing::warn!.

This is the default. It logs the error and signal type but not the full payload. Uses target otel_lifecycle so it can be filtered via RUST_LOG=otel_lifecycle=warn.

Stdout

Write failed exports as JSON to stdout.

Useful for Lambda where stdout goes to CloudWatch Logs. The output is a JSON object with signal_type, error, and request fields.

Stderr

Write failed exports as JSON to stderr.

File(PathBuf)

Write failed exports as protobuf files to a directory.

Files are named {signal_type}-{timestamp_ms}.pb.

Custom(Arc<dyn FallbackHandler>)

Use a custom fallback handler.

Implementations

impl ExportFallback

pub fn custom<F>(f: F) -> ExportFallback

where F: Fn(ExportFailure) -> Result<(), Box<dyn Error + Sync + Send>> + Send + Sync + 'static,

Creates a custom fallback from a closure.

Example

use opentelemetry_configuration::ExportFallback;

let fallback = ExportFallback::custom(|failure| {
    // Write protobuf bytes to your preferred destination
    let bytes = failure.request.to_protobuf();
    eprintln!(
        "Failed to export {} ({} bytes): {}",
        failure.request.signal_type(),
        bytes.len(),
        failure.error
    );
    Ok(())
});

pub fn handle(&self, failure: ExportFailure)

Handles a failed export using this fallback strategy.

Errors are logged via tracing with target otel_lifecycle. To see these warnings, enable the target in your RUST_LOG filter: RUST_LOG=otel_lifecycle=warn

Trait Implementations

impl Clone for ExportFallback

fn clone(&self) -> ExportFallback

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ExportFallback

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

Formats the value using the given formatter.

impl Default for ExportFallback

fn default() -> ExportFallback

Returns the “default value” for a type.