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structured logging

Logging named fields a machine can search, not just sentences.

Structured logs emit key-value fields (often as JSON) so they can be filtered and aggregated, e.g. status=500 route=/items.

Examples

  • info!(sailing, seats, "seats booked") prints INFO seats booked sailing="09:15" seats=3, with each fact as a named field.

See also

tracing span log level OpenTelemetry
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