Files
BitLogger/docs/api/configured-logger-drain.md
T
2026-05-12 14:17:19 +08:00

2.0 KiB

name, group, category, update-time, description, key-word
name group category update-time description key-word
configured-logger-drain api runtime 20260512 Drain queued work from a configured runtime logger with optional item limits.
logger
runtime
queue
public

Configured-logger-drain

Drain queued work from a ConfiguredLogger. This helper is useful when config-driven queue wrapping should be advanced in a controlled, bounded way.

Interface

pub fn ConfiguredLogger::drain(self : ConfiguredLogger, max_items~ : Int = -1) -> Int {}

input

  • self : ConfiguredLogger - Config-driven runtime logger whose queued work should be drained.
  • max_items : Int - Optional upper bound on how many queued items to drain. Negative values mean no explicit bound.

output

  • Int - Number of drained items.

Explanation

Detailed rules explaining key parameters and behaviors

  • Queue-wrapped sinks may drain up to max_items records.
  • For plain file sinks, the runtime falls back to file flush behavior instead of queue draining.
  • For sinks without queue semantics, the result is typically 0.
  • This helper delegates to RuntimeSink::drain(...) through the configured logger wrapper.

How to Use

Here are some specific examples provided.

When Need Bounded Queue Progress

When queued output should be advanced in chunks:

let drained = logger.drain(max_items=16)

In this example, callers limit how much queued work is processed in one step.

When Need Full Manual Drain

When the configured queue should be emptied explicitly:

ignore(logger.drain())

In this example, the configured runtime logger drains without imposing an item cap.

Error Case

e.g.:

  • If the runtime sink is not queue-backed, draining may return 0 or follow fallback flush behavior.

  • If callers only need generic flush semantics, flush() may be the simpler API.

Notes

  1. Prefer this helper when queue progress should be bounded or observable.

  2. Use pending_count() to inspect remaining backlog after the drain call.