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Protos

std:logging/JsonFormatter

std:logging/JsonFormatter

Section titled “std:logging/JsonFormatter”

Canonical occurrence: protos/lib/logging/JsonFormatter.protos · Protos revision: e99b712ecf658a527b1fe82c8beba2c1286d8dc9.

Deterministic JSON rendering of std:logging/LogEvent values over std:json. Each event renders as one compact JSON object with no line terminator, source metadata, color, or terminal control sequence:

{["timestamp":INTEGER,]"level":LEVEL,"message":STRING,"fields":OBJECT[,"error":true]}

For example {"level":"ERROR","message":"failed","fields":{"requestId":"r-7"},"error":true}. The members always appear in that order. "timestamp" appears exactly when the event has a timestamp and is the exact signed Integer count of nanoseconds of that std:datetime/Instant from 1970-01-01T00:00:00Z, without range limits; an event without a timestamp has no such member. fields is always present, {} when the event has no fields, and holds every field nested inside it, so a field may use any name, including timestamp, level, message, fields, or error. "error":true appears exactly when an Error is attached; the attached Error is never inspected, so every Error renders the same marker.

Structured data maps to JSON nodes of std:json, which alone owns string escaping and number spelling: null, Booleans, and Strings map to the same JSON values; Arrays keep their order; Maps become objects whose members are in ascending order of their names’ Unicode scalar sequences at every depth (the first differing scalar decides, and a proper prefix comes first). An Integer is the exact JSON number of the same value, without range limits. A finite non-zero Float is the decimal with the fewest significant digits that round-trips to the same binary64 value, the same decimal std:logging/TextFormatter renders. Both 0.0 and -0.0 render as the number 0, so JSON output does not preserve the sign of a zero. NaN, Infinity, and -Infinity have no JSON form and signal an Error.

Observable top-level slots

Section titled “Observable top-level slots”

This page lists the complete mechanically observable top-level slot inventory required by D067. Authored documentation, when present, is canonical D062 prose; mechanical presence alone does not create a stability or compatibility promise.

format

Section titled “format”

Answers the compact JSON text of event, which must be recognized by std:logging/LogEvent. Any other argument, or a field holding NaN, Infinity, or -Infinity, signals an Error before any text is produced. Rendering invokes no behavior stored in the event.

Mechanical facts

Section titled “Mechanical facts”

No callable shape is mechanically recorded for this slot.

Exact module source · Standard-library API · Standard library overview