Enum OutputFormat 

pub enum OutputFormat {
    ExitCode,
    Json,
}

How the framework extracts metrics from a payload’s output.

ExitCode records only the exit code; no text parsing. Json finds a JSON document region and walks numeric leaves into Metric values.

For Json, extraction is stdout-primary with a stderr fallback: the extractor runs first against stdout, and only when that yields an empty metric set AND stderr is non-empty does it retry against stderr. Well-behaved binaries keep stdout canonical; payloads that emit structured output only on stderr (schbench’s show_latencies → fprintf(stderr, ...)) still parse. The streams are never merged. ExitCode produces no metrics from either stream — extract_metrics is invoked (the control flow is variant-agnostic for simplicity) but the ExitCode arm returns Ok(vec![]) immediately, so the stderr fallback runs and also returns empty. Observable behavior: exit code only, no metrics.

Variants

ExitCode

Pass/fail from exit code alone. Stdout is archived for debugging but not parsed. extract_metrics is still invoked in the evaluate pipeline (variant-agnostic control flow) but returns Ok(vec![]) immediately for this variant; the stderr fallback runs too and also returns empty. Observable behavior: no metrics extracted regardless of stream content.

Json

Parse the primary stream (stdout, or stderr on fallback) as JSON: find the JSON region within mixed output, extract numeric leaves as metrics keyed by dotted path (e.g. jobs.0.read.iops).

Trait Implementations

impl Clone for OutputFormat

fn clone(&self) -> OutputFormat

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OutputFormat

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

Formats the value using the given formatter.

impl Copy for OutputFormat